10
Acra Oncologica Vol. 33, NO. 8, pp. 849-858, 1994 DESCRIPTIVE EPIDEMIOLOGY OF CANCER AROUND THE BALTIC SEA MATI RAHUand TIMO HAKULINEN Baltic Sea countries-Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, the Russian Federation and Sweden-have expressed deep interest in developing collaborative research projects chiefly in descriptive epidemiology of cancer. In order to assess potentials for joint studies, an attempt was undertaken to characterize cancer registration, cancer incidence patterns, temporal trends in cancer mortality and research productivity between these countries. Standards of cancer registration are highest in the Nordic countries (Denmark, Finland, Sweden). These countries and Germany are also doing more productive research. Great differences in incidence and in mortality trends around the Baltic Sea offer promising opportunities for epidemiologic studies. Scarcity of well-trained professional epidemiologists and other resources in Latvia, Lithuania, Estonia and the Russian Federation is the main factor limiting the planning of joint large-scale epidemiologic studies of cancer. Beginning with the new openness period of the mid- 1980s, and especially after the collapse of the USSR, the countries around the Baltic Sea expressed a sharply grow- ing interest in mutual contacts in different areas. The reasons for such an interest stem primarily from geograph- ical proximity, common history (1) and, quite often, from the fact that the Baltic is today one of the most polluted seas in the world (2, 3). In the field of joint efforts in descriptive epidemiology of cancer, several recent projects (4-7) can be mentioned. The most productive has been the long collaboration between the five Nordic countries (8- 1 l), of which three belong to the Baltic Sea region. Previ- ous projects have usually reflected collaborative research Received 20 January 1994. Accepted 1 May 1994. From the Department of Epidemiology and Biostatistics ( M. Rahu). Institute of Experimental and Clinical Medicine, Tallinn, Estonia. and the Finnish Cancer Registry (T. Hakulinen), Helsinki, Finland and the Unit of Cancer Epidemiology (T. Hakulinen), Karolinska Institute, Stockholm, Sweden. Correspondence to: Professor Mati Rahu, Department of Epi- demiology and Biostatistics, Institute of Experimental and Clinical Medicine, Hiiu 42, EE0016 Tallinn, Estonia. Part of this paper was presented at the symposium ‘Epidemiology around the Baltic Sea’, Stockholm, October 19, 1992. This study was conducted within the framework of the ‘Biostatistics and Modern Epidemiology’ Collaborative Program of the Finnish Cancer Registry and the Institute of Experimental and Clinical Medicine. activities of some Baltic Sea countries. However, only recently have prospects for common epidemiological stud- ies of all nine areas-Denmark, Estonia, Finland, Ger- many, Latvia, Lithuania, Poland, the Russian Federation (in the following called, for brevity, Russia) and Sweden- been discussed ( 12). The present study was initiated to examine the status of cancer registration and to present the main cancer inci- dence and mortality data for each of the nine Baltic Sea countries. In addition, an attempt was made to estimate the share and potential of each country in promoting epidemiological studies of cancer. Although the differences between countries in registration coverage, data quality and research scope have caused some heterogeneity in presentation and interpretation, this article can serve as a general reference for specialists who wish to find pertinent information about the Baltic Sea countries in a single publication. Material and Methods When European Russia is included, the nine countries adjacent to the Baltic Sea together cover a territory of 6.5 million km2 that forms 63% of Europe. Their total popula- tion of 272 million constitutes 38% of Europe’s popula- tion. The Baltic Sea countries differ from each other by size of territory and various major vital statistical charac- teristics (Table 1). 0 Scandinavian University Press 1994. ISSN 0284-186X 849 Acta Oncol Downloaded from informahealthcare.com by Michigan University on 11/05/14 For personal use only.

Descriptive Epidemiology of Cancer Around the Baltic Sea

  • Upload
    timo

  • View
    212

  • Download
    0

Embed Size (px)

Citation preview

Page 1: Descriptive Epidemiology of Cancer Around the Baltic Sea

Acra Oncologica Vol. 33, NO. 8, pp. 849-858, 1994

DESCRIPTIVE EPIDEMIOLOGY OF CANCER AROUND THE BALTIC SEA

MATI RAHU and TIMO HAKULINEN

Baltic Sea countries-Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, the Russian Federation and Sweden-have expressed deep interest in developing collaborative research projects chiefly in descriptive epidemiology of cancer. In order to assess potentials for joint studies, an attempt was undertaken to characterize cancer registration, cancer incidence patterns, temporal trends in cancer mortality and research productivity between these countries. Standards of cancer registration are highest in the Nordic countries (Denmark, Finland, Sweden). These countries and Germany are also doing more productive research. Great differences in incidence and in mortality trends around the Baltic Sea offer promising opportunities for epidemiologic studies. Scarcity of well-trained professional epidemiologists and other resources in Latvia, Lithuania, Estonia and the Russian Federation is the main factor limiting the planning of joint large-scale epidemiologic studies of cancer.

Beginning with the new openness period of the mid- 1980s, and especially after the collapse of the USSR, the countries around the Baltic Sea expressed a sharply grow- ing interest in mutual contacts in different areas. The reasons for such an interest stem primarily from geograph- ical proximity, common history (1) and, quite often, from the fact that the Baltic is today one of the most polluted seas in the world (2, 3). In the field of joint efforts in descriptive epidemiology of cancer, several recent projects (4-7) can be mentioned. The most productive has been the long collaboration between the five Nordic countries ( 8 - 1 l) , of which three belong to the Baltic Sea region. Previ- ous projects have usually reflected collaborative research

Received 20 January 1994. Accepted 1 May 1994. From the Department of Epidemiology and Biostatistics ( M. Rahu). Institute of Experimental and Clinical Medicine, Tallinn, Estonia. and the Finnish Cancer Registry (T. Hakulinen), Helsinki, Finland and the Unit of Cancer Epidemiology (T. Hakulinen), Karolinska Institute, Stockholm, Sweden. Correspondence to: Professor Mati Rahu, Department of Epi- demiology and Biostatistics, Institute of Experimental and Clinical Medicine, Hiiu 42, EE0016 Tallinn, Estonia. Part of this paper was presented at the symposium ‘Epidemiology around the Baltic Sea’, Stockholm, October 19, 1992. This study was conducted within the framework of the ‘Biostatistics and Modern Epidemiology’ Collaborative Program of the Finnish Cancer Registry and the Institute of Experimental and Clinical Medicine.

activities of some Baltic Sea countries. However, only recently have prospects for common epidemiological stud- ies of all nine areas-Denmark, Estonia, Finland, Ger- many, Latvia, Lithuania, Poland, the Russian Federation (in the following called, for brevity, Russia) and Sweden- been discussed ( 12).

The present study was initiated to examine the status of cancer registration and to present the main cancer inci- dence and mortality data for each of the nine Baltic Sea countries. In addition, an attempt was made to estimate the share and potential of each country in promoting epidemiological studies of cancer. Although the differences between countries in registration coverage, data quality and research scope have caused some heterogeneity in presentation and interpretation, this article can serve as a general reference for specialists who wish to find pertinent information about the Baltic Sea countries in a single publication.

Material and Methods

When European Russia is included, the nine countries adjacent to the Baltic Sea together cover a territory of 6.5 million km2 that forms 63% of Europe. Their total popula- tion of 272 million constitutes 38% of Europe’s popula- tion. The Baltic Sea countries differ from each other by size of territory and various major vital statistical charac- teristics (Table 1).

0 Scandinavian University Press 1994. ISSN 0284-186X 849

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 2: Descriptive Epidemiology of Cancer Around the Baltic Sea

850 M. RAHU AND T. HAKULINEN

Table 1 Characteristics of the Baltic Sea countries“

Country Territory Population Infant Total Births Life 1 000 death rate fertility outside expectancy km2 Total Age Age per 1 000 rate‘ of at birth

(mill.) 0-14 65 ~ birthsb marriage (years) ( ”/U) ( o/.) ( u/.)

Denmark Estonia Finland Germany Latvia Lithuania Poland Russiad Sweden

43.1 45.2

337.2 356.8 64.6 65.2

312.7 4552.0 450.0

5.1 I .6 5.0

80.0 2.7 3.8

38.2 127.0

8.6

17 22 19 16 21 23 25 23 18

16 11 13 15 12 I I 10 10 18

7.5 14.7 5.8 7.5

1 1 . 1 10.7 16.0 17.8 5.6

1.7 2.2 1.7 1.5 2.0 2.0 2.0 2.0 2.1

46 25 19 16 16 7 6

14 52

75 71 75 76 70 72 72 70 78

a The table is based mainly on the data by Haub & Yanagishita (13). Vital rates are usually for 1990. Presumably, the reported infant death rates for Estonia, Latvia, Lithuania and Russia would increase by 22-25%) if the WHO

recommended definitions of a live birth and an infant death were applied (14). ‘The total fertility rate is the average number of children a woman would bear in her lifetime given the age-specific birth rates in a particular year.

Territory arid population are given for the European part of the Russian Federation. Other data characterize both European and Asian territories of this country.

Most cancer incidence data and related registration in- formation used to describe the Baltic Sea countries were derived from the last volume of ‘Cancer incidence in five continents’ (C5C) (15). The data on cancer incidence in Lithuania were obtained from the Lithuanian Cancer Reg- istry (Dr J. Kurtinaitis). For most of the territories de- scribed, the data cover the years 1983-1987; data for Finland are from the period 1982-1986, for Cracow City and Nowy Sacz Rural areas (NSRA) 1983-1986, for Lower Silesia 1984-1987, and for Opole 1985- 1987.

Overall progress in controlling cancer was assessed by time trends in mortality rates for all sites of neoplasms (malignant and benign) combined. Cancer mortality rates for Denmark, Finland, Germany ( G D R and FRG), Poland and Sweden were extracted from a current publication ( 16). Information on mortality rates for Estonia was taken from a recently published paper ( 17). Incidence and mortality rates have been standardized by age, using the world population as standard. The abbreviation ASIR is used in the following for the age-standardized incidence rate.

Not all data sets were available to an equal extent for each of the nine Baltic Sea countries. In such cases no attempts were made to estimate missing incidence numbers of cancer for the country on the basis either of incidence data from regional registries or of national mortality rates. Because of the lack of information for several cancer sites in Lithuania, the percentage of cases verified histo- logically was estimated (as a crude approximation) as an arithmetical average of related percentages for Estonia and Latvia.

Research productivity was measured by publication ac- tivity and by the number of on-going projects. The number of papers published was assessed through computerized literature searches using the databases of cancer-related records from CANCERLIT and EMBASE (Cancer CD, 1984-1987, and January 1988-May 1992) issued by the U.S. National Library of Medicine. For searching specific records in the databases the following approach was used. First, the country’s name or an appropriate adjective (e.g. ‘Denmark’ or ‘Danish’) in an address field, and the term ‘cancer’ were selected. Second, the search was made more specific using the operator OR for combining the search terms ‘incidence’, ‘mortality’, ‘case-control’ and ‘cohort’. And finally, the search was restricted by excluding the terms ‘surgery’, ‘treatment’, ‘therapy’ and ‘animal’. For Russia, the main emphasis was on St. Petersburg, due to its proximity to the Baltic Sea and the availability of cancer incidence data. Thus, in an address field ‘Leningrad’ or ‘Petersburg’ was used, and in the latter case care was taken to exclude the records with authors from the State of Florida, U.S.A. For Germany the terms ‘Germany’, ‘FRG’. ‘GDR’, BRD’. ‘DDR’ and ‘German’ were applied. As a result of searches the number of rele- vant records (publications) was fixed for each country.

The number of on-going projects was found using the PROSE database (Version I .2, November 1991) provided by the IARC and the German Cancer Research Center (18). In a country field an appropriate country was chosen and subsequently the number of projects was found. For the former USSR the number of projects coming from

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 3: Descriptive Epidemiology of Cancer Around the Baltic Sea

CANCFK AROUND THE BALTIC SEA 85 1

Leningrad (St. Petersburg) was later specified from the corresponding publication ( 18).

Results and Discussion

Cancer registration

All Baltic Sea countries have population-based cancer registries (Fig. I), but they vary in the proportion of population covered by registration and in data quality. Table 2 lists some features characterizing cancer registra- tion in 15 registries. The Nordic countries (Denmark, Finland, Sweden) and the Baltic countries (Estonia, Latvia, Lithuania) have nationwide cancer registries. Among them the Danish Cancer Registry (started in 1942) is the world's oldest registry covering a whole country. In three other countries-Germany, Poland and Russia- there are, in fact, regional cancer registries only; the pro- portion of population covered by registration in these countries is 22%, 16% and 4% respectively.

In Germany, the National Cancer Registry of the GDR working during the period of 1953-1989 covered all popu- lation of the ex-GDR. Another population-based registry in Germany presented in the latest volume of the C5C (15)-the Cancer Registry of the Saarland-has in its catchment area a population of 1.1 million, that is 1.4'%1 of the total population of the country. One of the oldest population-based cancer registries, established in Hamburg at the end of the 1920s, faces serious problems with data completeness as a result of data protection legislation ( 19.

Fig. 1. Population-based cancer registries with reasonably com- parative data sets in the Baltic Sea countries. around 1983- 1987 (data mainly from (IS)).

20). In Poland, where the Polish Cancer Registry is claimed to be since 1952 'one of the few registries in the world to cover a country's entire population' of about 38 million (in 1988) (21), but where the six most successful

Table 2 Cliaracteristirs of population-based cancer registration in [he Baltic Sea countries"

Cancer registry's area of Territory Population Year First year Publication Data coverage 1000 (mill, ) registry with of annual published

km' started population- statistical in C5C based data reports volumes available

Denmark 43.1 5.1 I942 I943 Yes Estonia 45.2 1.5 1978 1968 No Finland 337.2 4.9 1952 1953 Yes Germany. GDR 108.3 16.7 1953 1953 Yes

Saarland 2.6 1.1 1967 I967 Yes Latvia 64.6 2.6 I977 1961 No Lithuaniah 65.2 3.5 1975 1961 N o Poland. Cracow City 0.3 0.7 1965 1965 Yes

Lower Silesia 18.9 1.6 1962 1962 No Nowy Sacz Rural 5.0 0.4 1975 1975 N o Opole 8.5 I .o I980 1975 No Warsaw City 0.4 1.6 1952 1963 No WarSdW R U d 6.2 0.6 I963 1963 No

Russia, St. Petersburg I .4 4.8 I980 I960 No Sweden 450.0 8.4 I958 1958 Yes

Based mainly on the data by the monograph 'Cancer incidence in five continents' ( 15). Data provided kindly by the Lithuanian Cancer Registry. A limited number of sites is given in Supplement to 'Cancer incidence in five continents', vol. 3 (28).

1-6 6' 1-6 2-6 3-6 6' No' 2-6 6 5-6 6 2-6 3, 4. 6 6 1-6

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 4: Descriptive Epidemiology of Cancer Around the Baltic Sea

852 M. RAHU ANDT. HAKULINEN

registries represent the country, issues of data complete- ness are also of great concern. The same is true of Russia, where the existence of real population-based cancer reg- istries is debatable (22). The status of cancer registration techniques in St. Petersburg has been convincingly docu- mented (23).

In the Baltic countries the most information is available about the Estonian Cancer Registry, which has published a description of its registration system (24, 25) and some statistical data (26, 27). Foreign readers have a very lim- ited knowledge of the activities of the population-based cancer registries in Lithuania and Latvia. Statistical data from these two registries (28, 29) have been displayed primarily as an integral part of the ex-USSR cancer regis- tration system, i.e., with a limited number of sites. in broad age groups, and without indicators revealing the reliability of registration (30).

The front-runners in cancer registration are the Nordic countries. In Denmark (31) and Finland (32) the cancer registries have been actually transformed into research institutes of cancer epidemiology; in Denmark the registry undergoes regular international scientific evaluations. In the Nordic countries multiple elements of total data in- frastructure-e.g., personal identification number system, computerized central population registry, automatic record linkages-ensure that cancer statistics meet the most rig- orous quality standards. Efforts have been made by cancer registries to apply several procedures for measuring the quality of registration (33 -35).

The remarkable variety in cancer registration in the Baltic Sea countries is apparent in Table 3. The low numerical value of one of the data quality indices-the proportion of cases recorded with histological verification of diagnosis-in some areas, e.g. Latvia and St. Peters- burg, presumably reflects gaps in information flow rather than the true situation. The last columns in Table 3 give the proportion of those cancers for which a primary site of origin was not established. Variation from 0.8% to 6.3% is largely caused by inter-registry differences in defining this item.

Cancer incidence

Tables 4 and 5 give relative frequencies and ranks of individual cancer sites occurring most often. Among males in all areas but Sweden, lung cancer ranks first. In Lower Silesia it accounts for one-third of all new cancer cases in males. In Sweden, prostate cancer is the most common cancer, responsible for 24.2% of incident cases. In Russia, Poland and the Baltic countries stomach cancer ranks second. Among females in all 15 areas, breast cancer is the leading cancer. Its proportion varies from 15.2% (NSRA) to 25.4%) (Finland). The second most frequent cancer site in six areas is stomach and in five areas uterine cervix.

For closer examination of cancer incidence in the Baltic Sea countries, age-standardized incidence rates for 1 1 areas have been chosen. For Germany two available data sets-

Table 3 Basic data from the population-bused cancer registration in rhe Baltic Sea countries around 1983- 1987"

Cancer registry's area of Average annual Histological Mortality/ Primary site coverage No. of incident cases verification incidence ratio ('XI) uncertain ('%I)'

Males Females Males Females Males Females Males Females

Denmark Estonia Finland Germany, G D R

Saarland Latvia Lithuania" Poland, Cracow City

Lower Silesia Nowy Sacz Rural Opole Warsaw City Warsaw Rural

Russia, St. Petersburg Sweden

12679 2135 8906

24944 2416 3156 4570

909 2148 459

1325 2324

676 6678

19263

12895 2364 9745

296 I9 2442 3403 4488 1017 1915 38 I

1130 2767

529 8645

18652

92 78 95 85 85 49 54 62 53 48 64 60 44 48 97

92 85 95 89 87 64 61 66 62 50 71 66 54 60 96

69 77 65 71 70 80 73h 83 78 82 73 84 89 74h 54

Based mainly on the data by the monograph 'Cancer incidence in five continents' ( 15) Includes skin cancer.

Data provided kindly by the Lithuanian Cancer Registry. ' Among all cases excluding non-melanoma skin cancers.

61 64 56 62 63 65 61 68 65 74 65 72 80 55h 50

3.3 I . 8 2.3 1.6 5.5 0.9 I .o 4.3 3.5 3.5 3.5 4.0 3.0 1.1 3.4

3.7 1 .o 3.4 1.9 6.3 0.8 0.9 4.7 4.3 5.4 4.0 4.4 4.3 1.2 3.9

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 5: Descriptive Epidemiology of Cancer Around the Baltic Sea

CANCER A R O U N D THE BALTIC SEA 853

Table 4 Runk order rind proportions (%) of most frequent cancer sites in nirrnhers of cases (eucluding non-melanoma skin cancers) in males in the

Baltic Sea c,ountries. around 1983- 1987"

Registry's area of coverage Oesophagus Stomach

Denmark NAPb 6 4.7 Estonia NAP 2 15.4 Finland NAP 3 8.1 Germany. GDR NAP 3 9.8

Saarland NAP 5 6.9 Latvia NAP 2 15.6 Lithuania' NAP 2 17.0

Lower Silesia NAP 2 8.6 Nowy Sacz Rural NAP 2 16.1 Opole NAP 2 10.4 Warsaw City NAP 2 9.4 Warsaw Rural NAP 2 12.0

Russia. St. Petersburg 6 4.0 2 19.0 Sweden NAP 5 5.6

Poland, Cracow City NAP 2 11.2

Colon Rectum Pancreas

4 7.8 5 6.4 NAP 4 5.0 5 4.7 7 4.2 5 4.8 6 4.1 7 4.0 6 6.0 4 6.7 NAP 3 8.1 6 5.8 NAP 7 4.4 6 4.5 4 5.1

NAP 4 5.3 6 4.4 NAP NAP NAP NAP 6 4.1 NAP NAP NAP NAP NAP NAP NAP

4 5.2 7 4.1 NAP NAP NAP 5 4.2

3 6.4 4 5.7 NAP 3 7.5 6 5.0 NAP

Larynx Lung Prostate Bladder Kidney

NAP 1 21.1 2 12.7 NAP 1 27.2 3 7.7 NAP 1 26.1 2 15.0 NAP 1 24.8 2 10.3 NAP 1 23.5 2 10.4 NAP 1 28.3 3 7.3

7 4.2 I 25.8 3 9.2 3 5.4 1 31.0 4 4.4 3 5.9 1 33.3 5 4.7 5 5.0 1 28.2 3 6.9 3 6.0 1 31.0 5 5.2 6 4.7 1 28.6 3 5.3 4 5.3 I 32.8 3 5.6

NAP 1 7.7 5 4.8 NAP 2 10.2 1 24.2

3 9.7 NAP 6 4.6 NAP 4 5.3 8 4.0 5 6.6 7 4.4 4 7.9 NAP 5 4.7 NAP 5 4.7 NAP 6 4.0 5 4.0 4 5.3 NAP 4 6.0 NAP 4 5.4 NAP 5 5.0 8 4.0 6 4.2 NAP 7 4.0 NAP 4 7.1 7 4.3

Based mainly on the incidence data in "Cancer incidence in five continents" (15). Only those sites are selected for which the proportion is at least 4'%; for other sites NAP (not applicable) is used

NAP = not applicable. Data provided kindly by the Lithuanian Cancer Registry.

one for Saarland, the other for the GDR-are displayed. For Poland an urban area (Cracow City) and a rural area (NSRA) were selected. There is great variation in cancer incidence between countries (Figs. 2 and 3). In males, concerning all cancers combined, Saarland has the highest ASlR that exceeds 1.5 times that in NSRA. Lung cancer incidence is highest in St. Petersburg, whereas its incidence in Sweden is remarkably lower than in the other countries. Cancer of the stomach dominates in St. Petersburg,

whereas Germany and the Nordic countries are character- ized by the lowest rates. In contrast, high occurrences of prostate cancer are seen in the Nordic region and Ger- many, with particularly high risk in Sweden. The Nordic countries and Germany also predominate in the case of urinary bladder cancer; there is, in fact, a 2.6-fold varia- tion in incidence between Denmark and Cracow. Colon and rectal cancers are more common in Saarland, Den- mark and St. Petersburg, whereas the lowest rates have

Table 5 Rank order mid proportions (?/) of most frequent cuncer s i t c v in numhers of cases (excluding non-melanoma skin cancers) in females in the

Baltic Seu countries. around 1983- 1987"

Registry's area of coverage Stomach Colon Rectum Gallbladder Pancreas Lung Breast Cervix Corpus Ovary uteri uteri

Denmark NAPb 2 9.6 6 4.9 Estonia 2 12.5 6 6.9 7 5.4 Finland 2 7.3 3 6.7 8 4.2 Germany, G D R 4 7.4 3 8.4 6 6.3

Saarland 3 6.8 2 10.9 5 5.5 Latvia 2 11.7 6 6.1 8 5.1 Lithuania' 2 12.4 8 5.2 6 5.6 Poland. Cracow City 4 6.6 7 4.9 9 4.1

Silesia 5 6.2 7 4.3 8 4.2 Nowy Sacz Rural 2 13.6 NAP 7 4.3

Warsaw City 8 5.8 6 5.8 9 4.2 Warsaw Rural 3 7.9 9 4.2 8 4.2

Russia, St. Petersburg 2 16.4 3 9.2 4 6.5 Sweden NAP 2 8.6 5 4.2

a As in Table 4.

Opole 3 7.5 8 5.1 7 5.4

NAP = not applicable. Data provided kindly by the Lithuanian Cancer Registry.

NAP NAP NAP

NAP NAP NAP

NAP NAP NAP

8 4.7

8 4.2

7 5.8 7 5.6

NAP NAP

NAP 3 8.8 1 24.1 7 4.9 4 5.7 5 5.4 NAP 8 5.0 I 18.9 3 7.8 5 7.0 4 7.5

6 4.5 7 4.3 I 25.4 NAP 4 6.0 5 4.9 NAP NAP I 22.2 2 8.8 5 7.1 7 5.9 NAP NAP 1 23.9 7 4.2 4 6.7 6 4.3

9 4.7 7 5.5 1 19.5 5 7.1 3 8.8 4 7.8 NAP 7 5.3 1 18.7 3 9.3 5 6.9 4 8.1 NAP 3 7.6 1 21.8 2 10.0 6 5.4 5 6.1 NAP 3 7.6 1 18.2 2 12.7 4 6.5 6 6.0

6 4.7 5 5.5 1 15.2 3 8.6 8 4.1 4 7.7 NAP 5 6.1 1 17.3 2 9.9 6 5.9 4 6.5 NAP 2 9.2 1 19.4 3 7.8 4 6.1 5 5.9 NAP 6 6.3 1 16.7 2 10.3 4 6.7 5 6.4 NAP 5 5.7 1 19.7 8 5.0 7 5.6 6 5.7 NAP 6 4.2 1 25.0 NAP 4 5.1 3 5.6

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 6: Descriptive Epidemiology of Cancer Around the Baltic Sea

854 M. RAHU AND T HAKULINEN

ALL SITES LUNG

ASIR, per 100 000 0 20 40 60 80

ASIR, per 100 000 0 50 100 150 200 250 300 350

Germany, Saarland Russia, Sf. Petersb.

Denmark Finland

Sweden Estonia

Germany, GDR Poland, Cracow City

Lithuania

I 78 Russia, St. Petersb.

Poland, Cracow City Germany, Saarland

Estonia Finland

Latvia Germany, GDR

Lithuania

3m 279

Denmark Poland, NSRA

Sweden ;

B Latvia

Poland, NSRA Zl

198

0 20 40 60 80 100 Histological verification, %

0 20 40 60 80 100 Histological verification, %

STOMACH

ASIR, per 100 000 0 10 20 30 40 50 60

PROSTATE

ASIR, per 100 000 0 10 20 30 40 50 60

Sweden Finland

Russia, St. Petersb. Lithuania

Estonia Latvia

5 0 2

% I s-; , : . Denmark

Germany, Saarland Germany, GDR

Lithuania Estonia

Latvia I 5 3

Russia, St. Petersb. 13 9

Poland, NSRA 1 2 6

Poland, Cracow City 105

0 20 40 60 80 100 Histological verification, %

Sweden Denmark 125

0 20 40 60 80 100 Histological verification, %

COLON BLADDER

ASIR, per 100 000 0 5 10 15 20 25 30 ASIR, per 100,000

0 5 10 15 20 25 30 Denmark

Germany, Saarland Sweden

Germany, GDR Finland Estonia

Russia, St. Petersb. Poland, NSRA

Latvia Lithuania

Poland, Cracow City

Germany, Saarland Denmark

Russia, St. Petersb. Sweden

German GDR kstonia Finland

F.. . 11 1

102 . 10 1

SO

0 20 40 60 80 100 Histological verification, %

0 20 40 60 80 100 Histological verification, %

RECTUM LARYNX

ASIR, per 100 000 ASIR, per 100 000 0 5 10 15 20 0 5 10 15 20

Poland, Cracow Ci 123

Poland, NSRX Lithuania

Latvia Russia, St. Petersb. Germany, Saarland

Estonia Denmark

German GDR pinland

Sweden

0 20 40 60 80 100 0 20 40 60 80 100 Histological verification. % Histological verification, YO

Denmark German , Saarland Russia, &. Petersb.

German ,GDR Jweden

Lithuania Estonia Finland

Latvia

Poland, NSR! Poland, Cracow Ci

Fig. 2. Age-standardized incidence rates (ASIR, world population) and histological verification percentages for selected cancer sites in the Baltic Sea countries in males, around 1983- 1987. The all sites category excludes non-melanoma skin cancers.

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 7: Descriptive Epidemiology of Cancer Around the Baltic Sea

C A N C t K \ROIIND THE BALrlC SFA

69 . 6 3 .

855

Lithuania Poland, NSRA

ALL SITES

I I . 128 -

BREAST

Denmark Sweden Estonia

Latvia Lithuania

Germany, GDR Poland, Cracow City Russia, St. Petersb.

Poland, NSRA Finland

Germany, Saarland

ASIR, per 100 000 0 50 100 150 200 250 300 350

149 . 146

( 2 8 . 1 2 1

$ 2 6 . ( 2 1

(18 . I , 3 . I ? t

0 9 5

ASIR, per 100 000 0 10 20 30 40 50 60 70 80

Denmark Sweden

Germany, Saarland Finland

German GDR Russia, St. Fhersb. Poland, Cracow City

Estonia Latvia

Lithuania Poland. NSRA

Denmark 2% . Sweden m - _ _ _

Germany, Saarland German GDR

Finland Russia, St Petersb. Poland, Cracow City

Estonia Latvia p? . . . ;

21 1, - -

0 20 40 60 80 100 Histological verification. YO

0 20 40 60 80 100 Histological verification, YO

CERVIX UTERI STOMACH ASIR, per 100 000

0 5 10 15 20 25 30 ASIR, per 100 000 0 5 10 15 20 25 30

253

I 8 8 . Germany, GDR

Poland, Cracow City Denmark Lithuania

Estonia Poland, NSRA

Latvia Germany, Saarland Russia, St. Petersb.

Sweden Finland

Russia, St. Petersb. Estonia

Lithuania Latvia

Poland, NSRA Germany, Saarland

Finland Germany, GDR

Poland, Cracow City Sweden

Denmark

r; 112

11 2

r 1 : : 9 , 11 3 . , 108

8 7

4 4

0 20 40 60 80 100 Histological verification. YO

0 20 40 60 80 100 Histological verification, YO

CORPUS UTERI OVARY

ASIR, per 100 000 0

Denmark Germany, GDR

Germany, Saarland Latvia

Sweden 12 I

Finland Estonia

Russia, St. Petersb. Lithuania

Poland Cracow Ci $eland, NSRx

0 20 40 60 80 Histological verification, YO

LUNG COLON

ASIR, per 100 000 0 5 10 15 20

6 8

38 -

ASIR, per 100 000 0 5 10 15 20 25 30 25 30

Germany, Saarland Denmark Sweden

Russia, St. Peters. Germany, GDR

Finland Estonia

Latvia Poland, Cracow City

Lithuania Poland, NSRA

Denmark Poland, Cracow City

Sweden Russia, St. Petersb.

Estonia Finland

Germany, Saarland Latvia

m;' . .

=i3 . Lithuania Germany, GDR Poland, NSRA

0 20 40 60 80 100 Histological verification, YO

0 20 40 60 80 100 Histological verification, YO

Fig. 3. Age-standardized incidence rates ( ASIR, world population) and histological verification percentages for selected cancer sites in the Baltic Sea countries in females, around 1983- 1987. The all sites category excludes non-melanoma skin cancers.

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 8: Descriptive Epidemiology of Cancer Around the Baltic Sea

856 M. R A H U ANDT. HAKULINEN

been shown in NSRA. Laryngeal cancer is more common in Poland and Lithuania; this cancer occurs four times more often in Cracow than in Sweden. A measure of data quality-the proportion of histological verification -sug- gests that the registered incidence rates are as a rule more reliable in the Nordic countries and Germany.

In females, total cancer incidence in Denmark is twice that in NSRA. For breast cancer, the areas under study are ranked about in the same sequence as for all cancers combined. The incidence rate for this cancer in Denmark exceeds three times the rate in NSRA. For stomach cancer, the ASIR in St. Petersburg is over four times higher than in Denmark. The highest rate of cervical cancer occurs in the G D R and the lowest one in Finland; cervical cancer patterns and the substantial reduction in the incidence and mortality in Finland closely correlate with the intensity of organized screening (36). The GDR/Finland ASIR ratio is 5.8. The highest rates for endornctrial and ovarian cancers are experienced in Denmark. As for males, cancer of the colon is common in Saarland and in Denmark, and rare in Poland and in Lithuania. Women living in Denmark ap- pear to be especially at risk for lung cancer. Thus, ASIR in Denmark is 1.8 timcs greater than that in Cracow, which ranks second; the Denmark/NSRA ratio is 3.8. Again. the Nordic countries and Germany have thc highest propor- tions of cases verified histologically.

The observed differences in cancer incidence between the countries are impressive and substantial, and in spite of variability in registration practices the differences provide important information for comparative epidemiological studies.

Time tvrnds in t o t d cuncer niortrdity

Total cancer mortality patterns differ substantially across the countries around the Baltic Sea. At present, comparable data for Latvia. Lithuania and. presumably, Russia (i.c., St. Petersburg) exist in the form of tabulations but, unlike the situation in Estonia (17). they have not been analyzed or provided for public use. Among malcs, Poland and Estonia have the highest age-standardized mortality in 1985-1989 (Fig. 4), and the lowest mortality occurs in Sweden. Among females. Denmark ranks highest whereas Finland ranks lowest (Fig. 5 ) .

General trends in cancer mortality over time are more often increasing among males than among females. In males, the greatest increase is seen in Poland. Estonia and Denmark. Between the time periods 1965- 1969 and 1985- 1989, mortality in Poland increased by 30.5‘%1. A 15.8’%1 decrease was observed in Finland. In females, Denmark had a slight increase of 2.1%: mortality decreased by 14.1% in Germany (FRG) and by 13.6‘%, in Finland.

Temporal trends in Swedish cancer mortality rates have been influenced by a change in coding practices in 1981 (37) . Data that have been available for the GDR begin

80 4 c 80 1965-69 1970-74 1975-79 1980-84 198589

Period

Fig. 4. Age-standardized mortality rates ( ASMR. world popula- tion) for cancer in 1985-1989 and percentage change in age- standardized mortality from cancer in the Baltic Sea countries in males. from 1965- 1969 to 1985- 1989.

110 105 1 I105

Denmark

100.

95 -

90 Gamny.Fff i - 116 90 P O W -104

85- EW -im srrdan B 101

80 80 196569 1970-74 1975-79 1980-84 1985-89

Period

Fig I Age-standardizcd mortality rates ( ASMR. world popula- tion) for cancer in 1985- 1989 and percentage change in age- standardized mortality from cancer in the Baltic Sea countries in females. from 1965 1969 to 1985- 1989.

Gemwv.GDR - 106

with thc period 1970-1974 (16): therefore. the related trend curves would be comparable with the curves for other countries if there wcrc no change in age-standardized mortality in the GDR between the first and second quin- quennia. Although there might be other imprecisions limit- ing comparability of cancer mortality across the Baltic Sea countries, i t is evident that substantial ditfercnces in time trends exist. Moreover. since these trends directly signal the extent of progress in cancer control (38-40). Figs. 4 and 5 summarize the level of efforts to control cancer.

Rrsrnrclr uctiiVtics

Tablc 6 demonstrates deep contrasts between the Baltic Sea countries in research activities. Judging by the num- bers of publications and on-going research projects. epi- demiologists from Germany. Sweden and Denmark are the largest contributors. A very poor record of publications and on-going research characterizes the Baltic countries

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 9: Descriptive Epidemiology of Cancer Around the Baltic Sea

CANC FR 4ROI YD T H E BALTIC SFA 857

Table 6 Number qf pcrpers published (Cancer-CD. 1 9 8 4 / M a ~ 1992) trrt i l

thu/ of' on-p ing projects (PROSE. 1992) in the ,field o/' c w m ' r epidemiology in rke Baltic Sea countries

Country/region Cancer-CD PROSE

REFERENCES I . Runblom H. Tyden M. Carlbick-lsotalo H. The Baltic Sea

environment. Session 4: The Baltic region in history. Uppsala: Uppsala University, 1991,

2. Arby G . Joint action on polluted Baltic. Enviro 1990; 10: 12 3. 3. Backlund P. Holmbom B. Leppikoski E. The Baltic Sea

environment. Session 5: Industrial emissions and toxic pollu- tants. Uppsala: Uppsala University. 1992.

4. Staneczek W, Rahu M. Berndt H. Verinderungen der Krebs- inzidenz in der DDR von 1968 bis 1981. 2 Arztl Fortbild 1988:

5 . Karjalainen S. Aareleid T, Hakulinen T. Pukkala E. Rahu M. Tekkel M. Survival of female breast cancer patients in Fin- land and in Estonia: stage at diagnosis important determinant of the difference between countries. Soc Sci Med 1989: 28: 233-8.

6. Aareleid T , Pukkala E. Thomson H. Hakama M. Cervical cancer incidence and mortality trends in Finland and Estonia: a screened vs. an unscreened population. Eur J Cancer 1993: 29A: 745-9.

7. Nilsson B. Gustavson-Kadaka E. Rotstein S. Hakulinen T. Rahu M, Aareleid T. Cancer incidence in Estonian migrants to Sweden. Int J Cancer 1993: 55: 190-5.

8. Hakulinen T, Andersen A. Malker B. Pukkala E. Schou G. Tulinius H. Trends in cancer incidence in the Nordic countries. A Collaborative Study of the Five Nordic Cancer Registries. Acta Pathol Microbiol Imniunol Scand 1986: 94: (Suppl 28X).

9. Tulinius H. Storm HH. Pukkala E. Andcrscn A. Ericsson J . Cancer in the Nordic countries. 1981 86. A Joint Publication of the Five Nordic Cancer Registries. Acta Path01 Microbiol Immunol Scand 1992: 100: (Suppl 31).

10. Jensen OM. Carstensen B. Glattre E, et al. Atlas of cancer incidence in the Nordic countries. Helsinki: Nordic Cancer Union, 1988.

1 I . Engeland A. Haldorsen T. Tretli S. et al. Prediction o f cancer incidence in the Nordic countries up to the years 2000 and 2010. A Collaborative Study of the Five Nordic Cancer Registries. Acta Pathol Microbiol lnimunol Scand 1993: 101: (Suppl 38).

12. Adami H-0 . Hakulinen T. Stanecrek W. Excellent opportuni- ties for collaboration i n cancer epidemiology. SVEPET 1992: (4): I-9.

13. Haub C. Yanagishita M. Europe population data sheet. Wash- ington: Population Reference Bureau. 1991.

14. Anderson BA. Silver BD. Infant mortality in the Soviet Union: regional differences and measurement issues. Population and Development Review 1986: 12: 705 ~ 38.

15. Parkin DM. Muir CS. Whelan SL. Gao YT. Ferlay J. Powell J, eds. Cancer incidence i n five continents. Vol. VI. IARC Scientific Publications No. 120. Lyon: International Agency for Research on Cancer. 1992.

16. La Vecchia C. Lucchini F. Negri E. Boyle P. Maisonneuve P. Levi F. Trends of cancer mortality in Europe. 1955 1989: V. Lymphohaemopoietic and all cancers. Eur J Cancer 1997: 28A: I 509 -81.

17. Leinsalu M. Rahu M. Time trends in cancer mortality in Estonia. 1965-1989. Int J Cancer 1993: 53: 914-8.

18. Coleman M. Wahrendorf J , Deniaret E. eds. Directory of on-going research in cancer epidemiology 1992. IARC Scien- tific Publications No. 1 1 7. Lyon: International Agency for Research on Cancer. 1992.

19. Krebs in Hamburg. Neumeldungen 1988 des Hamburgischen Krebsregisters. Todesursachenstatistik der biisartingen Neu- bildungen 1979 bis 1988. Hamburg: Hamburgisches Krebsre- gister. 1991.

82: 27-31.

Demark Estonia Finland Germany Latvia Lithuania Poland Russia. St. Petersburg Sweden

239 4

172 43 1

48 7

317

48 2 36 59

22

82 1 -

and Russia (St. Petersburg). However, some of the Russian- language references may have lacked the authors' addresses. During the past decades, researchers from these countries have been facing serious problems in conducting meaning- ful epidemiologic studies for political and economic reasons (30). The long isolation of epidemiologists and potential epidemiologists in Baltic countries and Russia has made these countries now the weakest link in the chain.

Certainly. the varying willingness and ability of scientists to report on current projects to the Clearinghouse for On-going Research on Cancer Epidemiology may limit the comparability of epidemiologic research activities pre- sented in Table 6. Even so, the drastic differences between the countries are portrayed.

Again, in spite of reservations about the validity of the presented data. these major differences clearly demonstrate the research potentials in the countries addressed.

Concluding remarks

Our intention is to stimulate useful research in cancer epidemiology in the Baltic Sea region. At present. i t is possible to demonstrate the existence of considerablc differences. both in cancer incidence by site and i n cancer mortality trends, between the Baltic Sea countries. The differences generally offer diverse and inspiring opportuni- ties for inter-country comparisons of patterns. trends and determinants of cancer in the Baltic Sea region. At the same time i t has become clear that the prerequisites for collaboration cannot be easily realized because of inequal- i ty of resources. including availability of professional epi- dcmiologists. across the countries.

ACKNOWLEDGEMENTS The personal computer and software used in word processing

by M. Rahu were obtained thanks to grant GF-41901 awjarded by the Norwegian Cancer Society. We thank Dr Juozas Kurtinaitis for his cooperation in this project. and Professor Brian Silver. Mrs Carolyn Schmidt and two anonymous referees for useful com- ments on an earlier draft.

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.

Page 10: Descriptive Epidemiology of Cancer Around the Baltic Sea

20. Muir CS. Demaret E. Cancer registration: Legal aspects and confidentiality. In: Jcnsen OM. Parkin DM. MacLennan R. Muir CS. Skeet RG. eds. Cancer registration: principles and methods. IARC Scientific Publications No. 95. Lyon: International Agency for Research on Cancer, 1991: 199 207.

21. Wronkowski Z. Bielska-Lasota, M. Vital statistics iii Poland. I n : Zatonski W, Boyle P. Tyczynski J , eds.. Proceedings o f the International Conference on Cancer Prevention: Vital Statis- tics to Intervention; 1988 Oct 12- 14; Warsaw. Warsaw: PA Interpress. 1990: 18-24.

22. Filatov V. Untitled abstract. In: Abstracts of the Cancer Work-shop of the Symposium on Epidemiology around thc Baltic Sea: 1992 Oct 19- 21: Stockholm. Stockholm: Swedish Medical Society. 1992.

23. Merabishvili VM, Kiselnikova IV, Kolovsky NL. Kapitonova OA. Russia. St Petersburg. In: Parkin DM, Muir CS. Whel:iti SL. Gao YT, Ferlay J. Powell J. eds. Cancer incidence i n five continents, Vol. VI. IARC Scientific Publications No. 120. Lyon: International Agency for Research on Cancer. 1992: 710-3.

24. Staneczek W, Rahu M, Beckmann L, et al. A conipuriitive study of cancer registries in the German Democratic Republic and the Estonian SSR. Arch Geschwulstforch 1982: 52: 575 83.

35. Rahu M . Estonia. In: Parkin DM. Muir CS. Whelan SL. Gao YT. Ferlay J. Powell J, eds. Cancer incidence in livc conti- nents. Vol. VI. IARC Scientific Publications No. 120. Lyon: International Agency for Research on Cancer. 1992: 509 73.

26. Rahu M. Cancer occurrence in Estonia. In: Bentham G. Haynes R. Langford I , eds. Proceedings of the Fourth Inter- national Symposium in Medical Geography; 1990 JUIY I0 19: Norwich. Norwich: University of East Anglia. 1990: I04 7.

37. Aareleid T. Rahu M. Cancer survival i n Estonia from 197X to 19x7. Cancer 1991; 68: 2088~~92.

2X. Napalkov NP, Tserkovny GF, Merabishvili VM. Parkin DM. Snians M, Muir CS, eds. Cancer incidence in the USSR (Suppl. to Cancer incidence in five continents. Vol. 3 ) 2nd

revised ed. IARC Scientific Publications No. 4'8. Lyon: lnter- national Agency for Research on Cancer. 1983.

29. Zaridze DG. Gurevictus R. Lung cancer in thc USSR: pat- terns and trends. In: Zaridze DG. Pcto R. eds. Tobacco: ii

major international health hazard. IARC Scientific Publica- tions No. 74. Lyon: International Agency for Research on Cancer. 19x6: 87 101.

30. Rahu M. Cancer epidemiology in the former Soviet Union. Epidemiology 1992; 3: 464 70.

31. Jensen OM. Ewertz M. Lynge E. Olsen JH, Schou G. Storm HH. eds. Danish Cancer Society. Danish Cancer Registry: Triennial Report 1986 19x8. Copenhagen: Danish Cancer Society. 1989.

31. Saxen E. Teppo L. Finnish Cancer Registry 1952 1977. Hensinki: Finnish Cancer Registry. 197X.

33. Saxcn EA. Teppo L. Hakulinen T. Quality control of cancer registry data. In: Nieburgs HE. ed. Prevention and detection of cancer. Part I, Prevention, Vol. 2. Etiology. prevention methods. New York: Marcel Dekker. 1978: 2151 64.

34. Mattsson B. Cancer registration i n Sweden: studies on coni- pleteness and validity of incidence and mortality registers. Stockholm: Karolinska Hospital. 19x4.

35. Storm H H . Completeness of cancer registration in Denmark 1943 1966 and eficacy of record linkage procedures. l i l t J Epidemiol 19XX; 17: 44 9.

36. Hakama M. Magnus K. Pcttersson F. Storm H . Tulinius H . Erect of organizcd scrcening on the risk of cervical cxiccr i n the Nordic countries. I n : Miller AB. Chamberlain J. Day NE. Hakama M. Prorok PC'. eds. Cancer screening. Cambridge: Cambridge University, 1991: 153 02.

37. Rutqvist LE. Mattsson B. Signoniklao T. Ciincer mortality trends in Sweden I960 19x6. Actn Oncol 1989: 2X: 771 5.

3X. Bailar JC. Smith EM. Progress against cancer? N Engl J Med 19x0; 314: 1226 32.

39. Extramural Committee to Asses?, Measures of Progress Against Cancer. Measurement 01' progress against ciiticer. J Natl Cancer Inst 1990: 82: X25 35 .

40. Adami H - 0 . What is progress against cancer? Cancer Causes Control 1993: 4: 4x3 7.

Act

a O

ncol

Dow

nloa

ded

from

info

rmah

ealth

care

.com

by

Mic

higa

n U

nive

rsity

on

11/0

5/14

For

pers

onal

use

onl

y.