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has occurred. There is a high incidence of lung can-

cer in females, the ratio of male: female

is 1.87:1 in Guangzhou. Lung cancer death rate in females closely connected with coal consumption not only in Guangzhou city but also in other Chinese metropo- lises and counties. Using other fuels for cooking instead of coal might be an impor- tant measure to prevent lung cancer.

The Use of Linear Regression to Model Lung Cancer. Mortality Map Patterns. Piantadosi, S., Byar, D., Mason, T. National Cancer Institute, NIH, Bethesda, MD, U.S.A.

The purpose of this work is to describe simple methods for the analysis of geo- graphic patterns of disease mortality or incidence with emphasis on lung cancer in the U.S.A. Geographically based data have been increasingly used to generate hypotheses about environmental causes of cancer, and present special problems of analysis. For example the "ecological fallacy" may limit the interpretability of results, and spatial nonrandomness may affect significance tests. Lung can- cer mortality presents additional problems because of the unavailability of geogra- phic data on cigarette consumption and the lag in time between exposure and death. This paper outlines methods to cope with these problems and constructs a simple predictor of the geographic pat- tern of lung cancer mortality. Age adju- sted lung cancer mortality in white males during the period 1950-1969 based on state economic areas was used. Plausible surrogates for cigarette consumption were thought to be standardized mortality ratios for chronic bronchitis and emphysema. 73% of t~e variation in mortality, as measured by R , was explainable by simple linear regression models containing such variab- les as a smoking surrogate, measures of urbanicity, median income, ethnic compo- sition, industrial employment and other. Performance of models was tested, in part, using color coded maps. The models are consistent with previously recognized sociodemographic associations with lung cancer and also generate new hypotheses which may deserve further investigation.

Lung Cancer Epidemiological Evidence in

Italy. 1 Zanetti , M2, Montaguti I, U., Fiacchi 2, M., Morrone , G. Medical Direction, S. Orsola Hospital, Bologna, Italy. Thoracic Surgery Institute, Bologna, Italy.

The frequency of tumors, and particu- larly of lung cancer, as causes of death is constantly increasing in Italy as in

most affluent Countries.

The analysis of lung cancer mortality trends shows in Italy some interesting and singular characteristics.

In this lecture a description is given of the present epidemiological situation (sex, age, and geographic distributions) of lung cancer. A brief discussion is made on a datum relevant to the Italian young male population: in Italy, starting from the end of the the se- venties, 35-44 years old males show the high- est lung cancer mortality rate, compared to the rates shown by all the other industrialized countries.

The possible relationships between this phe- nomenon and the history of tobacco consumption in Italy are discussed.

Lung Cancer in Newfoundland & Labrador. Ganguly, P., Guy, J., Moores, D., Norris, B. Newfoundland Lung Cancer Clinic, St. John's Newfoundland, Canada.

This study was carried out with two objecti- ves:

i. provide a detailed epidemiological survey, 2. investigate and correlate basic clinical

parameters. The population of 579,000 was studied using

parameters including age, sex, employment, in- come, smoking habit, ethnic groups, industry, and air pollution. During the study period 1974 - 1983, 1,466 cases of primary lung can- cer were registered.

In the ten provincial census divisions there was no association of incidents to study para- meters except in two mining areas where the rates were twice the mean rate.

The symptoms, investigative findings, patho- logical classification, operability and survival of a subset of 563 lung cancer cases from Janu- ary 1977 to December 1983 were studied.

Mechanism of Interactions between Asbestos Fibers and Proteins. Valerio, F., Balducci, D. Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.

Interaction between proteins and asbestos has an important role in many biological ef- fects (emolysis, citotoxicity).

A first attempt to define mechanism was car- ried out.

Single proteins and total serum proteins ad- sorption isotherms were obtained using chryso- tile and crocidolite, and protein composition was evaluated before and after incubation. Two different and concurrent adsorption mechanisms were observed, the first aspecific and rever- sible, the second selective and involving strong bonds. Molecular weight of proteins selectively adsorbed was evaluated.

Experiments carried out with single proteins demonstrated that adsorp£ion capability of as- bestos fibers was not correlated with protein charge or with molecular weight, while amount of adsorbed proteins, in particular on chryso-

tile, was a linear function of proteins charge