Incidence of cutaneous malignant melanoma in Granada (Spain) 1985-1992 Ricardo Ocaña-Riola, PhD Andalusian School of Public Health Granada - Spain

Incidence of cutaneous malignant melanoma in Granada (Spain)

1985-1992

Ricardo Ocaña-Riola, PhD

Andalusian School of Public HealthGranada - Spain

© Ricardo Ocaña-Riola

The authorThe author

Address for correspondenceRicardo Ocaña-RiolaEscuela Andaluza de Salud PúblicaCampus Universitario de Cartuja, s/nApdo de Correos 207018080 Granada (Spain)

Ricardo Ocaña-RiolaProfessor of Biostatistics

Andalusian School of Public Health

[email protected]

Webwww.easp.es

Escuela Andaluza de Salud Pública

References

mailto:[email protected]

http://www.easp.es/


FrameworkFrameworkFrameworkFramework

Tumours derived from melanocytes– The commonest in humans– Most of them are benign– They sometimes are converted into

malignant melanomasRelevance of malignant melanoma

– High incidence among younger cohorts– Increase in its incidence



FrameworkFramework

0% 2% 4% 6% 8% 10%

HUNGARY, Szabolcs-Szatmar

SLOVENIA

NEW ZEALAND, No Maoris

DENMARK

NORWAY

EEUU, Hawai

Increase of incidence (1960-1985)

Female MaleSource: Armstrong and Kricker, 1994



FrameworkFramework

Results from international studies– Different world wide incidence rates– Different world wide survival rates– Different risk and prognosis factors

Why population-based studies?– Knowledge of our population– Contribution to improve health care



ObjectivesObjectivesObjectivesObjectives

Main objective

Specific objectives1. To estimate the standardised incidence rates2. To describe the incidence trends3. To study the incidence geographical pattern4. To describe the characteristics of the incident cases

Population-based study of cutaneous malignant melanoma in the Granada province , 1985-1992



MethodologyMethodologyMethodologyMethodology



Scope of the studyScope of the study



Design, patients and sourcesDesign, patients and sources

Descriptive studyPatients

– All cases diagnosed from 1985 to 1992– 247 incident cases of melanoma– All of them live in the Granada province

Source of information– Granada Cancer Registry



VariablesVariables

SexAge (years)Anatomic siteHistological type (ICD-O)Clark level (I-V)Breslow thickness (mm)



Statistical data analysisStatistical data analysisStatistical data analysisStatistical data analysis

World population standardised incident rates– ASRW (x100.000 inhabitants)– To compare different populations

Univariate and bivariate analysis– Descriptive tables– Chi-squared test– T-Student test



Statistical data analysisStatistical data analysis

Trend analysis– Smoothing (moving averages)

• To see the real trend of incidence• To delete random fluctuations into the time

series

– Standardised rates by periods• 1985-87, 1988-1990 y 1991-1992• To quantify the incidence rates change



Statistical data analysisStatistical data analysis

Geographical analysis– Standardised Incidence Rate (SIR)

• Calculated by the Indirect method• SIR=Observed/Expected• Population of reference: Granada province

– Bayesian models• Smoothing SIR • To control extra-Poisson variability• To detect clusters



Statistical softwareStatistical software

S-PLUS– Descriptive analysis– Trends analysis

WinBUGS– Bayesian models

EpiMap– Smoothing incidence maps



Results and DiscussionResults and DiscussionResults and DiscussionResults and Discussion



Incidence ratesIncidence rates

Incidence Mortality

Males Females Males Females

Cases 105 142 45 34

Crude Rate 3.4 4.4 0.9 0.6

ASRW 2.9 3.7 0.7 0.5

Cutaneous Malignant MelanomaGranada, 1985-1992.



Incidence ratesIncidence rates

Medium-low rates world-wideDifferent to other countriesDifferent risk factors

– Skin type (Zanetti et al, 1992)– Sun exposure (Aase and Bentham, 1996)

Incidence similar to rates in other Spanish cancer registries



World wide incidence ratesWorld wide incidence rates

0 5 10 15 20 25 30 35

SINGAPUR, Indios (1988-1992)

BIELORUSIA (1988-1992)

ALBACETE (1991-1992)

ASTURIAS (1988-1992)

ZARAGOZA (1986-1990)

MURCIA (1988-1992)

PAIS VASCO (1988-1991)

GRANADA (1985-1992)

NAVARRA (1987-1991)

TARRAGONA (1988-1992)

MALLORCA (1988-1992)

NORUEGA 1988-1992)

AUSTRALIA, Nueva Gales del Sur (1988-1992)

MALES

ASRW (x100.000)

World maximum

European maximum

World minimum

European minimum

Spain

Source: Cancer Incidence in Five Continents



World wide incidence ratesWorld wide incidence rates

0 5 10 15 20 25 30

SINGAPUR, Indias (1988-1992)

ITALIA, Ragusa (1988-1992)

ALBACETE (1991-1992)

TARRAGONA (1988-1992)

ZARAGOZA (1986-1990)

NAVARRA (1987-1991)

ASTURIAS (1988-1991)

GRANADA (1985-1992)

MALLORCA (1988-1991

PAIS VASCO (1988-1991)

MURCIA (1988-1992)

AUSTRIA, Tirol 1988-1992)

NUEVA ZELANDA: No Maoríes (1988-1992)

FEMALES

ASRW (x100.000)

World maximum

European maximum

World minimum

European minimum

Spain

Source: Cancer Incidence in Five Continents



Trends in melanoma incidenceTrends in melanoma incidence

1985-87 1988-90 1991-92Males 2.2 2.9 3.2

Females 3.0 3.4 4.7

Cutaneous Malignant Melanoma (ASRW)Granada, 1985-1992.



Trends in melanoma incidenceTrends in melanoma incidence

Increasing trendsAverage annual increase around 4%Similar increase in other countriesHypothesis for this fact

– Change in sun exposure (Pukkala, 1995)– Change in health care practices


GEOGRAPHICAL PATTERNCutaneous melanoma (Granada, 1985-1992)

SIR



Menos de 0.01

0.01 - 0.61

0.62 - 0.82

0.83 - 0.89

0.90 - 1.07

1.08 - 1.31

1.32 - 2.15

Ms de 2.15


Characteristics of incident casesCharacteristics of incident cases

Males Females

Cases 105 142

Age (mean) 57 years old 53 years old

Anatomic site Trunk (34%)Head (32%)

Low. limbs (44%)Head (23%)

Cutaneous Malignant MelanomaGranada, 1985-1992




Males Females

Histological type Superfic. (35%)Nodular (26%)

Superfic. (39%)Nodular (25%)

Clark level III (32%)IV (18%)

II (31%)III (29%)

Breslow (mean) 3.3 mm 2.4 mm

Cutaneous Malignant MelanomaGranada, 1985-1992




Incidence among younger cohorts– 1/3 of cases under 45 years– Contrast to other skin tumours– Melanoma non related to cumulative

dosage of sun exposure (Zanetti et al, 1992)Higher incidence among females

– Similar to other European Registries– Different to EEUU




Male and female dissimilarities– Anatomic site

• Trunk in males

• Lower limbs in females

• Are the differences due to clothes? (Aase et al, 1996)

– Clark level and Breslow• Lower in females

• Cultural differences between gender

• Early diagnosis (Armstrong et al, 1994)



ConclusionsConclusions




Medium incidence rates world-wideThe highest incidence rates are

located in the city of Granada and all the municipalities around it

There was an increasing trend in the incidence of melanoma from 1985 to 1992




FEMALES53 years oldMS SuperficialLower limbsLow-MediumLow-Medium

MALES57 years oldMS SuperficialTrunkMedium-HighMedium-High

CHARACTERISTICAgeHistological typeAnatomic siteClark levelBreslow

More frequent characteristics of incident casesCutaneous malignant melanoma

Granada, 1985-1992



This information, which corresponds to the province’s whole population, might guide health policies contributing to disease prevention and to a better care. Because of the increase in incidence rates and the high percentage of cases diagnosed at advanced stages, it is advised that prevention campaigns are addressed to the Granada population.



Documents

Incidence of cutaneous malignant melanoma in Granada (Spain) 1985-1992 Ricardo Ocaña-Riola, PhD Andalusian School of Public Health Granada - Spain