An Approach to Overcome the Limitations of Surveillance of Asbestos Related Diseases in Low- and Middle-Income Countries: What We Learned from the Sibaté Study in Colombia

Introduction

The asbestos industry began its operations in Colombia in 1942 with the establishment of an asbestos-cement facility in Sibaté, located in the Department of Cundinamarca. Despite extensive asbestos use and production in Colombia, the country lacks a reliable epidemiological surveillance system to monitor the health effects of asbestos exposure. The Colombian health information system, known as SISPRO, did not report mesothelioma cases diagnosed in the municipality, posing a significant challenge in understanding the health impacts of asbestos exposure on the population of Sibaté.

Methods

To address this issue, an active surveillance strategy was implemented in Sibaté. This strategy involved conducting door-to-door health and socioeconomic structured interviews to identify Asbestos-Related Diseases (ARDs). Validation strategies included a thorough review of medical records by a panel of physicians, and the findings were communicated to local, regional, and national authorities, as well as the general population.

Results

The active surveillance strategy successfully identified a mesothelioma cluster in Sibaté, revealing the inadequacy of the existing health information system in monitoring asbestos-related diseases. The discovery of this cluster underscores the critical importance of implementing active surveillance strategies in Colombia, where governmental institutions and resources are often limited.

Conclusion

The findings of this study emphasize the urgent need for Colombia to establish a reliable epidemiological surveillance system for asbestos-related diseases (ARDs). Active surveillance strategies can play a crucial role in identifying mesothelioma clusters and enhancing our understanding of the health effects of asbestos exposure in low- and middle-income countries.

The Italian Experience in the Development of Mesothelioma Registries: A Pathway for Other Countries to Address the Negative Legacy of Asbestos

Asbestos (all forms, including chrysotile, crocidolite, amosite, tremolite, actinolite, and anthophyllite) is carcinogenic to humans and causally associated with mesothelioma and cancer of the lung, larynx, and ovary. It is one of the carcinogens most diffuse in the world, in workplaces, but also in the environment and is responsible for a very high global cancer burden. A large number of countries, mostly with high-income economies, has banned the use of asbestos which, however, is still widespread in low- and middle-income countries. It remains, thus, one of the most common occupational and environmental carcinogens worldwide. Italy issued an asbestos ban in 1992, following the dramatic observation of a large increase in mortality from mesothelioma and other asbestos-related diseases in exposed workers and also in subjects with non-occupational exposure. A mesothelioma registry was also organized and still monitors the occurrence of mesothelioma cases, conducting a case-by-case evaluation of asbestos exposure. In this report, we describe two Italian communities, Casale Monferrato and Broni, that faced an epidemic of mesothelioma resulting from the production of asbestos cement and the diffuse environmental exposure; we present the activity and results of the Italian mesothelioma registry (ReNaM), describe the risk-communication activities at the local and national level with a focus on international cooperation and also describe the interaction between mesothelioma registration and medical services specialized in mesothelioma diagnosis and treatment in an area at high risk of mesothelioma. Finally, we assess the potential application of the solutions and methods already developed in Italy in a city in Colombia with high mesothelioma incidence associated with the production of asbestos-cement materials and the presence of diffuse environmental asbestos pollution.

[Thalidomide and unilateral limb defects: the Italian chapter of a neverending story]

Fifty years after the event, Italy introduced legislation to compensate malformations in children - now in their sixties - born to mothers who had been prescribed the antiemetic drug thalidomide for morning sickness. However, compensation has been denied to people 'only' damaged in one half of their body as opposed to those with bilateral malformations. The present study reviews the papers describing case series of children born with 'thalidomide embryopathy' in the UK, Germany, and other countries around 1960. Most clinical series were not organized on the basis of inclusion/exclusion criteria, thus allowing for probable selection and information biases on maternal use of thalidomide. In any case, they included a sizable number of children with a unilateral limb defect born from mothers certainly exposed to thalidomide during the relevant pregnancy. In many of these children, limb defects were associated with visceral malformations, as frequently observed following exposure to thalidomide in utero. Similarly, later literature reviews were not bias-free in their choice of articles, as is the case of a recently proposed 'diagnostic algorithm' for thalidomide-caused specific malformations and of the advice by the Italian National Institute of Health ruling out the possibility of thalidomide producing unilateral limb defects. Overall, the scientific evidence suggests that thalidomide can cause unilateral limb defects.

[Effects of Asbestos on Human Health. Document of the Italian Epidemiological Association (AIE)]

OBJECTIVES

the Italian Epidemiological Association (AIE) intends to formulate assessments and recommendations on the most relevant and critical aspects in the preparation, conduct, and interpretation of epidemiological investigations on the health effects of exposure to asbestos and asbestos-like fibres.

DESIGN, SETTING, AND PARTICIPANTS

the document was prepared by a working group of AIE associates, with a broad curriculum of epidemiological investigations, starting from the evaluation of scientific evidence, and was subsequently evaluated by the AIE governing body.

RESULTS

the topics covered included: • consumption and presence of asbestos; • association between asbestos exposure and disease; • epidemiological surveillance of asbestos related diseases in Italy; • risk function for asbestos related diseases; • increased risk and anticipation of the disease; • interaction between asbestos and other carcinogens; • diagnosis in epidemiological studies; • assessment of exposure to asbestos; • epidemiological evidence on asbestos related diseases.

CONCLUSIONS

the document ends with a summary of the conclusions of scientific research shared by AIE, with reflection on the methodology to be followed for the application at individual level of the results of epidemiological studies, and the proposal of themes on which to direct research.

An asbestos contaminated town in the vicinity of an asbestos-cement facility: The case study of Sibaté, Colombia

INTRODUCTION

The asbestos industry began operations in Colombia in 1942, with an asbestos-cement facility located in the municipality of Sibaté. In recent years residents from Sibaté have been complaining about what they consider is an unusually large number of people diagnosed with asbestos-related diseases in the town. A study to analyze the situation of Sibaté started in 2015, to verify if the number of asbestos related diseases being diagnosed were higher than expected, and to identify potential asbestos exposure sources in the town.

METHODS

A health and socioeconomic survey was implemented door-to-door to identify potential asbestos-related diseases. Several self-reported mesothelioma cases were identified, and for confirmation purposes, copies of the medical record with the histopathology report were obtained. A panel of six physicians analyzed the medical records. Information of validated cases was used to estimate the male and female age-adjusted incidence rate for Sibaté. Based on reports of the existence of potential asbestos-contaminated landfills, topographic maps, a digital elevation model, and current satellite images were crossed using a geographic information system to identify potential landfilled areas, and soils samples were collected in some of these areas.

RESULTS

A total of 355 surveys were completed, and 29 self-reported mesothelioma cases were identified. Twenty-five of these cases have been persons who had lived at some moment of their lives in Sibaté. It was possible to obtain copies of the medical diagnosis for 17 cases. Of these, the panel of physicians classified 15 cases as certain pleural mesothelioma, one as probable, and one as not mesothelioma. Based on this information, the estimated age-adjusted incidence rate of mesothelioma in Sibaté was 3.1 × 10⁵ persons-year for males and 1.6 × 10⁵ persons-year for females. These rates are high in comparison to those reported in other cities, regions, and countries of the world. Using geographic information systems, landfilled zones in the urban area of Sibaté were identified, on top of which a school and different sports facilities were built. The analysis of four soil samples collected in landfilled zones, confirmed the existence of an underground layer of friable and non-friable asbestos.

CONCLUSION

The collected evidence suggests the presence of a malignant pleural mesothelioma cluster in Sibaté.

Mesothelioma in Italy: the Casale Monferrato model to a national epidemiological surveillance system

The purpose of the present paper is to review the origin and development of the epidemiology of mesothelioma in Italy, starting with the detection and investigation of the major outbreak of the disease observed in Casale Monferrato, Piedmont Region. Over the last four decades, mortality among the cohort of ex-Eternit workers has been measured at three points in time. More recently, population based case-control studies in the area of Casale Monferrato have provided new light on the dose-response curve of the relationship between asbestos exposure and mesotheliomas. The publication of the first Casale Monferrato study had a major impact in the country and contributed to the decision of the Italian Parliament to ban the use of asbestos. The experience of Casale Monferrato represents a lesson in several terms, from the epidemiological surveillance to the health care of the victims and the relationship between epidemiologists, victims, their relatives and residents in contaminated areas.

Time Trends in Survival of Children with Acute Lymphocytic Leukemia in Piedmont, Italy: A Report from the Population-Based Cancer Registry

Aims and Background

The Childhood Cancer Registry of Piedmont (RTI) periodically updates the life status of each registered child. Given its size, the RTI is the major (albeit geographically limited) Italian source of population-based survival rates of cancer in children. The present report describes time trends in survival of children with acute lymphocytic leukemia (ALL).

Methods

During 1970-87, 429 residents in Piedmont aged 0-14 were diagnosed as having ALL: they have been followed up until 1991.

Results

Five-year survival rates increased from 21% to 72% for children diagnosed ALL respectively in 1970-72 and 1985-87. Major improvements occurred up to the mid-seventies and again between cases diagnosed in the early and late eighties. Improvement in survival was statistically significant for children belonging to classes comprised between 2 and 10 years of age at diagnosis. Period of diagnosis was unrelated to probability of survival among the 13 cases diagnosed ALL at age 0. Survival was unrelated to sex, even in the early seventies and even after consideration of children dying more than 5 years after diagnosis. Between 1976-81 and 1982-87, an improvement in survival was found in all categories of WBC count at diagnosis: the ratio between the two estimates was somewhat higher for children with more than 50,000 WBC/mm3 at diagnosis than for other children.

Conclusions

Present data are compared with those resulting from other population-based series: this exercise can be useful for an overall evaluation of delivery of cancer therapy at the population basis.

Survival after Pleural Malignant Mesothelioma a Population-based Study in Italy

Aims and Background

The study analyzed survival after malignant mesothelioma in the population-based Registry of Malignant Mesothelioma of Piedmont (NW Italy, 4.5 million total population). It focused on possible differences related to period of diagnosis a proxy of changes in diagnostic or therapeutic procedures.

Methods

Cases were actively searched in pathology units and files of hospital admissions and discharges. In 1990-1998, 693 incident cases were diagnosed in residents in the region: 590 of them had a histologic diagnosis of pleural mesothelioma in life and were included in the study. Vital status was ascertained at the municipality of residence as of January 1, 2000.

Results

Fifty-eight cases were alive (9.8%) and 20 were lost (3.6%) at the end of the follow-up. Median survival was 0.71 years (95% Cl, 0.64-0.78). Cumulative survival was 35.9% at 1 year (95% Cl, 32.0-39.8) and 14.2% at 2 years (95% Cl, 11.2-17.1). Survival was associated to age (longer survival for younger subjects at diagnosis; P <0.0001) and to histology (longer survival for epithelial mesothelioma, shorter for fibrous and intermediate for mixed or unspecified types; P <0.0001). There was no difference in survival for period of diagnosis. The results were confirmed in multivariate analyses. Analyses according to type of hospital (with vs without thoracic surgery) did not show any statistically significant difference.

Discussion

The study on survival after malignant mesothelioma is the second largest of the three population-based studies in the world, which showed results similar to ours. Survival measured in published clinical series ranged between 18.4% and 57.6% at 1 year for pleural and 24.1% and 33.8% for peritoneal mesothelioma. The most striking effect of the present study was the absence of improvement in survival with period of diagnosis. Either there was no change in treatment efficacy or the effect was limited to small subgroups and could not be noticed when the analysis included larger categories.

Descriptive Epidemiology of Cancer of the Larynx in the Province of Torino, Italy

Age-standardized incidence rates of cancer of the larynx in men from 1965–1969 were 14.7/100,000/year in the city of Torino and 8.4 in the non-metropolitan area of the province. These rates are among the highest in Europe. The geographical distribution of cancer of the larynx has been investigated in the non-metropolitan area considering two geographical entities, i.e., the 291 towns and the 12 ecological zones/subzones of the area. The incidence of cancer of the larynx in men was unrelated to the population of towns in 1961, whereas it was positively correlated to indexes of general industrialization as well as to those related to industrialization in the mechanical processes. Tobacco and alcohol consumption have not been taken into account. In order to validate the methodology, the investigation was extended to bladder cancer and to cancer in children. The former was correlated with general and chemical + rubber industrialization, whereas the latter was not correlated with any industrial process.

Parental Occupation and Other Environmental Factors in the Etiology of Leukemias and Non-Hodgkin'S Lymphomas in Childhood: A Case-Control Study

We report the results of a hospital-based, case-control study on acute lymphocytic leukemia (ALL), acute non-lympocytic leukemia (AnLL) and non-Hodgkin lymphoma (NHL) in childhood. The study was conducted from 1981 to 1984 in Turin (Italy). One hundred and forty-two children with ALL, 22 with AnLL and 19 with NHL were included, as well as 307 controls. Information on parental smoking habits, parental occupation, ionizing radiation and childhood diseases were collected using a standard questionnaire during a personal interview of the relative attending the child in the hospital. The odds ratios for antenatal diagnostic radiation were 1.1 (NS) for ALL and 2.4 (NS) for AnLL. No association was found with diseases in childhood. Paternal and maternal smoking habits were similar for ALL cases and controls. Both maternal and paternal smoking were associated with NHL: for paternal smoking, odds ratios were around 5, but without a correlation with number of cigarettes. Positive associations observed with maternal employment were: ALL with teacher and cleaner; AnLL and textile worker; NHL and baker. Corresponding association with paternal jobs were: ALL with clerks, farmers and employment in office equipment production; AnLL and workers in building, tire or textile industries; NHL and lorry drivers, workers in the building or in the wood and furniture industry.

Incidence of Breast Cancer in Piedmont: 1979–1981

A population-based survey of histologically diagnosed breast cancer was carried out among residents in Piedmont. A total of 5267 incident cases occurring in 1979–1981 was collected, corresponding to an age-standardized (on the world population) incidence rate of 49.5/100,000 per year. Rates (standardized on the population of Piedmont in 1981) were highest in the city of Torino (112.4/100,000 per year) and lowest in the province of Cuneo (67.5), whereas in the other provinces they ranged between 85.3 and 90.0. Estimation of rates in the 54 Local Health Authorities of Piedmont detected up to 2-fold differences between adjacent areas. A correlation was found between rates and size of the population of town of residence. Comparison with age-specific incidence rates from the Cancer Registry of the nearby province of Varese suggested a loss of nonhistologically confirmed cases selectively in older age groups. The distribution of cases diagnosed in 1979 by histologic type is presented. The proportion of diagnoses reported in terms which were consistent with the 1978 WHO Histological Typing of Breast Tumours was 61.3%. It was highest among cases identified in Pathology Services located in University Hospitals and/or diagnosing more than 50 breast cancers per year.

Cancer of the Breast in Women Born in Southern Italy and who Migrated to the City of Torino

Individual demographic data of 459 women living in Torino with incident breast cancer diagnosed in 1979 were compared with those of a random sample of 1800 women drawn from the list of residents in the same city. Among women aged 25–44 and 45+ years, age-adjusted odds ratios for birth in southern Italy were respectively 1.3 (95% CL, 0.1–2.1) and 0.7 (95% CL, 0.5–0.9). In women aged 45+ years, odds ratios increased with length of residence in Torino.

Bladder Cancer and Cigarette Smoking in Males: A Case-Control Study

Cigarette consumption was compared between 355 males with cancer of the lower urinary tract and 276 male hospital controls. Both duration of smoking and average daily consumption of cigarettes showed a dose-response relationship with risks of developing bladder cancer. Quitting smoking seems to have a protective role, whereas higher relative risks are associated with an early age at start of smoking. The use of a filter seems to have a weak protective effect.

Risk Factors for Soft Tissue Sarcomas in Childhood: A Case-Control Study

A hospital-based case-control study on soft tissue sarcomas (STS) was conducted in 1983-84 in Torino and in Padova (Italy). Cases (36 children with rhabdomyosarcoma (RMS) and 16 non RMS-STS) were compared to 326 controls. Histories of parental smoking habits and occupations, parental and children's exposure to ionizing radiation, children's diseases and some other variables were collected through interviews to the relatives attending the child in the hospital. A non statistically significant association was observed with both maternal age above 30 at child's birth (STS: OR = 1.5, C.I. = 0.8-2.9; RMS: OR = 1.9, C.I. = 0.9-4.0) and « in utero » exposure to diagnostic radiation (STS: OR = 1.9, C.I. = 0.5-6.5, based on 4 cases). No association was found with children's previous diseases. Paternal and maternal smoking habits were similar for RMS and STS cases and controls. Some positive associations with either maternal or paternal occupational histories were identified. They are difficult to interpret in view of the large number of comparisons and small absolute figures. They included maternal employment as medical doctor and nurse, farmer, textile worker and machine tool operator. An association was also observed with paternal occupation as butcher, building worker or employment in the production of domestic appliances. One case and no controls reported a maternal aunt affected by breast cancer.

Neurofibromatosis and Malignant Childhood Cancers: A Survey in Italy, 1970–83

Neural tumors, Wilms’ tumor, rhabdomyosarcoma and several types of leukemia have been previously described in association with neurofibromatosis (NF). In a nation-wide collection of cases in Italy, 15 children (0–14 years of age) with NF and cancer or leukemia were identified; 13 of them had been diagnosed with cancer between 1976–83. The expected number of children with cancer and NF in 1976–83 was 4.48. The distribution of tumor types was different from that found in the general population, with a higher proportion of tumors of neural crest origin as well as soft tissue sarcomas. In 7/15 the family history was positive for NF; in 5/7 the individuals affected included the mother and/or a maternal relative.

Mortality of Parents of Children with Cancer: A Population-based Study in Turin, Italy

Aims and Background

A cohort study was conducted in order to measure cause-specific mortality among parents of children recorded in the Childhood Cancer Registry of Piedmont. It is the first study carried out on the subject in southern Europe.

Methods and Study Design

The study comprised the 740 children resident in Turin and in whom a cancer had been diagnosed in the period 1967-1991. Nominal data were obtained for 723 fathers and 733 mothers. At the end of the follow-up in 1995, 645 fathers were alive, 68 dead and 10 untraceable. Corresponding figures for mothers were 700, 28 and 5. Cause of death was known for 91 of 96 parents.

Results

The period of observation of parents started on the birth of the index child, however mortality analyses were restricted to the period after 1965 because of limited availability of local reference rates. Total mortality was lower than expected among fathers (66 observed deaths vs 88.2 expected, P <0.05) and mothers (28 vs 31.4). Fathers showed deficits (not statistically significant) of lung neoplasms (4 vs 9.9), cardiovascular diseases (18 vs 27.1) and hepatic cirrhosis (2 vs 6.6). No statistically significant variations in mortality were observed with time from diagnosis or according to life status of the children. No cancer deaths occurred among the mothers of sarcoma cases whereas 1.9 were expected.

Conclusions

The data do not indicate any increase in mortality from cancer or other causes and, on the contrary, show a reduction in mortality which was more evident for the causes related to life style.

High Incidence of Laryngeal Cancer in the Province of Torino (Italy)

The present report shows that the province of Torino, Italy, (6830 sq Km, population in 1966, 2.074.893) is a high risk area for laryngeal cancer. A total of 875 cases occurring in residents in the province were forwarded to the Cancer Registry of Piedmont (RTP) in 1965–69. A histological report was available in 67.9 % cases, while in 21.8 % the death certificate was the only document with diagnosis of laryngeal cancer (table 1). Cases were uniformly distributed throughout the 5 years covered by the study: the number of cases with death certificate only progressively decreased from 59 in 1965 to 21 in 1969 (table 3). For the purposes of the present study, the province of Torino has been divided into 3 areas, i.e. the city of Torino (population 1.107.919), the 23 suburbs (total population 340.951) and the non-metropolitan part of the province (population 626.023). Among the three areas, the relative frequency of laryngeal cancer/all malignant tumours recorded at the RTP in men was 5.78 % in the city of Torino, 6.43 % in the suburbs and 4.77 % in the non-metropolitan part of the province (table 4). The difference between the city of Torino and the suburbs was not significant (p > 0.05) while the difference both between the city of Torino and the non metropolitan part of the province and between the suburbs and the non metropolitan areas was significant (p < 0.05 and p ∼ 0.01 respectively). In other cancer registries (3) the relative frequencies of laryngeal cancer were under 2.86 % with the exception of Israel (3.24 %) and Bombay (9.26 %). In women, the relative frequency of laryngeal cancer fluctuated between 0.25 and 0.32 % in the different areas of the province of Torino, i.e. in the same order of those observed in other cancer registries with the exception of Bombay (2.07%) (3). In the province of Torino considered as a whole, age standardized annual incidence/100.000 of laryngeal cancer was 12.6 in men and 0.6 in women. Incidences truncated to ages 35–64 were 25.5 and 0.9 respectively (table 5). In men these rates are approximately 5–7 times higher than those recorded in Norway, Sweden and Denmark and about 3.5–6 times higher than those recorded in the six cancer registries operating in Great Britain. A comparison between the province of Torino and other cancer registries on age specific incidences (table 6, text-fig. 3) shows that the ratio province of Torino/other registries is relatively higher at age 35–44 than later in life. This is considered as evidence of an increase of the environmental carcinogenic load in the province of Torino during recent years. In men, age standardized incidences and incidences truncated to ages 35–64 were slightly but not significantly higher in the city of Torino than in the suburbs. On the other hand, in both the city of Torino and the suburbs they were 1.5–1.7 times higher than in the non-metropolitan part of the province (table 5). The difference concerned mainly age groups over 55 (text-fig. 2). However, the incidence of laryngeal cancer truncated to ages 35–64 in the non-metropolitan part of the province of Torino was still 7.2 times higher than in the rural population of Norway and 2.1–4.1 times higher than in the six cancer registries operating in Great Britain (3). This suggests that factors connected with life in the metropolitan area of Torino (such as air pollution) are a minor cause of the excess of laryngeal cancer in the province of Torino.

Lack of Long-term Effects of the Administration of Heptachlor to Suckling Rats

95 Wistar rats were given 5 administrations of 10 mg/kg heptachlor in corn oil each by stomach tube, every second day starting at 10 days of age. Seven animals died before weaning. No early deaths were recorded among 36 controls given corn oil only. 29 experimental animals were killed at 60 weeks of age to detect early changes which were nevertheless absent. Growth and survival rates were similar in experimental and control animals. The incidence of tumors at different sites in males and that of adrenal, thyroid and pituitary tumors in females were comparable in both groups. 9 of 28 treated females developed a total of 12 tumors in various organs (including 5 mammary tumors and 2 renal lipomatous tumors) whereas 4 of 27 control females developed a total of 4 tumors (2 of which were located in the breast). In view of the different locations of the tumors and the lack of the reproducibility of the finding among males the results are not considered as evidence of carcinogenicity of heptachlor under the present experimental conditions.

Epidemiology of Childhood Cancer in Piemonte and Valle d'Aosta during 1965-69

Piemonte and Valle d'Aosta are in the NW part of Italy. In 1967 total population and population aged 0-14 were respectively 4.338.000 and 841.000. During the period 1965-69 a total of 688 cases of cancer (including leukemia) were diagnosed in children under 15 years of age resident in this area. The Cancer Registry of Piedmont and Valle d'Aosta (RTP) provided information on 465 children; the other 223 were collected through additional investigation in the files of 31 university or hospital departments of the region and 5 extraregional hospitals. Distribution through the 5 years covered by the investigation is shown in Table 1. Histological or hematological confirmation of the diagnosis was available in 499 cases (73%). The 688 cases included 216 leukemias, 131 tumors of the central nervous system, 40 neuroblastomas, 82 lymphomas (including 34 cases of Hodgkin's disease), 46 nephroblastomas, 32 soft-tissue sarcomas, 29 bone sarcomas (including 5 cases of Ewing's disease), 25 retinoblastomas, 12 thyroid tumors, 10 extragenital teratomas, 5 ovarian dysgerminomas, 4 tumours of the testes, 4 hepatoblastomas and 52 other tumours (Table 2). The number of children under 15 years of age dying of cancer during 1965-69 was 341 (Table 2). Incidence and mortality rates by age groups are given in Tables 3 and 4. The rates were of the same order as those observed in the U.S. and in other European cancer registries during the same period (Tables 4, 5 and 6). The mortality rate for nephroblastomas at age 0-4 was 1,09/100.000/year, i.e. slightly higher than that observed in the U.S. in 1960 but about twice as high as that observed in the U.S. in 1967 (14). Incidence and mortality rates for both Hodgkin's and non-Hodgkin's lymphomas were about 3 times higher in males than in females (Table 3). The difference was less obvious during the first five years of life, in which the total number of diagnosed lymphomas was 16.

A Study of Stress (Repeated Centrifugations) Interference with Subcutaneous Carcinogenesis in Mice

C3H and Swiss male mice were given a single subcutaneous injection of 1 mg methylcholanthrene and were subsequently centrifuged (5 weekly treatments for 5 weeks: at each treatment mice were centrifuged at 3.8 g for 1 h). Tumor incidence was 100 % in both stressed and non-stressed mice: no differences in survival time were observed.

Increase of Mortality Kate of Cancer of the Larynx in the Town of Torino and in Italy since 1951

Mortality rates of cancer of the larynx in the town of Torino, in the whole of Italy and in France during 1950–71 are reported. Age standardized mortality rates as well as mortality rates truncated to the period 35–64 years of age are reported in Table 1 for males and in Table 2 for females. Graph 1 represents age specific mortality rates for cancer of the larynx in the three areas in 1966–67. Graphs 2, 3 and 4 report mortality rates in males in the three ares for cohort of birth. All rates are annual/100.000. An increase of mortality for cancer of the larynx in men is well documented in the town of Torino. From 1951 to 1966 the mortality rate truncated to age 35–64 increased from 6.3 to 12.0. The proportion of mortality for cancer of the larynx/mortality for all cancers during the same period increased from 3.1 % to 5.4%. In Italy, the mortality rate in men aged 35–64 was 6.5 in 1952 and 9.3 in 1967: during the same period the proportion of mortality for cancer of the larynx/mortality for all cancers increased from 3.8 % to 4.4 %. In France, the tendency to an increase of mortality for laryngeal cancer after 1951 was absent or debatable, although both the mortality rates of cancer of the larynx and the proportion of mortality for cancer of the larynx/mortality for all cancers were consistently higher than in Italy or in Torino. However, in 1966–67 at ages 35–44 the mortality rate for cancer of the larynx in men was higher in Torino than in France (Graph 1).

A Study on the Role of Compensatory Hyperplasia in Renal Carcinogenesis with Dimethylnitrosamine in the Rat

Two experiments of renal carcinogenesis with dimethylnitrosamine (DMN) are described. In experiment I, the carcinogenicity of a single neonatal injection of DMN was compared in 34 intact rats and in 38 rats right-nephrectomized at 8–10 weeks of age. A total of 37 tumor-bearing kidneys were seen: both tubular and anaplastic; tumor incidence and time of observation showed no significant differences between intact and nephrectomized animals. Liver tumors were seen in 38 of 72 rats. In experiment II, 64 adult rats were given DMN in the drinking water for 2 weeks at a concentration corresponding to half an effective dose: 20 rats were used as non-nephrectomized controls; the others were right nephrectomized either on the 7th - 8th day of treatment with DMN or 15 days prior to the beginning of the treatment with the carcinogen. In no case did unilateral nephrectomy have a modifying effect upon carcinogenesis. In nephrectomized rats nonneoplastic nephritic changes were more severe than in intact animals. The design of the present experiments is compared with that of previous studies on the role of either partial hepatectomy or unilateral nephrectomy in carcinogenesis.

Storage Levels of Ddt Metabolites in Mouse Tissues following Long Term Exposure to Technical DDT

The storage levels of DDT and its metabolites, following the long term administration of technical DDT at the dose levels of 2, 20, 50 and 250 ppm to mice, were evaluated in the fat tissue, liver, kidney, brain and reproductive organs. In addition, storage levels were evaluated in foetuses and newborns of DDT-treated mothers. Apart from op'-DDT, there was a direct relationship between the concentration of each metabolite in each organ and the dose to which the animal was exposed. The highest concentration of DDT and metabolites was found in the fat tissue followed by reproductive organs, liver and kidney together, and lastly brain. The most prevalent metabolite was pp'-DDT, except in the liver, where pp'-DDD showed the highest concentration. Pregnant females had lower concentrations of all metabolites than non-pregnant females. The concentration of residues in samples of total foetal litters was directly related to the concentration of DDT fed to the mother. There was a strong negative correlation between the concentration of pp'-DDT and that of pp'-DDD in the foetuses and the placentas of the same litter. A significant increase in whole body DDT concentration was observed shortly after birth.

Physical Impairment and Social Life, Goals among Adult Long-term Survivors of Childhood Cancer: A Population-based Study from the Childhood Cancer Registry of Piedmont, Italy

Aims and Background

The study describes the health status and the attainment of life goals in the adult survivors of childhood cancer recorded at the Childhood Cancer Registry of Piedmont.

Methods and Study Design

A postal questionnaire was sent to the general practitioner of the 690 cases born before 1976 and alive in 1991 after at least 5 years from diagnosis. The answer was received for 485 (72.9%) included in the analyses. Items in the questionnaire were: sequelae related to cancer and its treatment, health-related quality of life (according to Bloom's criteria), educational level attained, and employment status.

Results

Vital and marital status were obtained for all 690 cases at the offices of the town of residence. No medical condition was reported for 309 cases (63.7%). The overall proportion with a high school or university education was compared to corresponding figures for Piedmont in 1991, adjusted by age, and was as high as in the general population. Similar results are observed for occupation. Patients of both genders were married less than expected. Patients with leukemia (112 cases), non-Hodgkin's lymphoma (34) or Hodgkin's lymphoma (52) were reported to have the highest quality of life. In contrast, patients with tumors of the central nervous system (151) had the highest frequency of sequelae and the lowest score for health-related quality of life. They also presented the lowest educational achievement, the lowest proportion of employment and, among males, the lowest frequency of marriage.

Conclusions

Our study shows a good social adjustment of adult survivors from childhood cancer, with the exception of central nervous system tumors. From the methodologic point of view, the present study shows the feasibility of surveillance surveys on health-related quality of life with the contribution of general practitioners.

Evaluation of the Carcinogenicity of the Chlorinated Hydrocarbons Used as Pesticides

The relevant information concerning the long-term experiments with the most commonly used chlorinated hydrocarbons are reviewed and tabulated. Some experiments with DDT, aldrin, dieldrin and heptachlor gave evidence of a weak carcinogenicity for laboratory animals; the results however have not been unequivocally confirmed. The following possibilities are discussed: 1) that the tumors produced in some experiments are related to a real carcinogenicity of the chemicals under investigation, 2) that they belong to the group of the « spontaneous » tumors, 3) that they are the result of a synergistic action of the pesticide and other factors. None of these suggestions can give a comprehensive interpretation of all the experimental results. It is emphasized that a dose-response relationship has not been demonstrated in any of the experiments under review and that, particularly for DDT, the purity of the chemical was reported only in a few instances. Carbon tetrachloride produced hepatomas in mice and hamsters; however, its use in agriculture does not appear to create a major carcinogenic hazard for men.

[Childhood cancer epidemiology and available evidence on case clustering]

This paper introduces a Monograph on childhood cancer clusters addressed to Italian public health workers, paediatricians and paediatric oncologists, and the general public. Two issues have been underlined in most definitions of cancer clusters reported in the literature over the last 30 years. The first is the need for an unbiased methodological approach for the detection and the interpretation of clustering and of individual clusters. The other is the responsibility for scientists and public health workers to unravel suspicious events and to interact with the population in circumstances which may turn out to be false alarms. The relative weight given to epidemiological methods and to risk perception has varied between definitions of clusters given in different periods. In the field of childhood cancer clusters, epidemiological research has produced very little fresh knowledge. However, it is recognized that this is not a sufficient reason for refusing to pay attention to reports of perceived clusters. Models of spatio-temporal interactions according to Birch et al. (2000) are taken in consideration: the literature offers a very limited number of circumstances fitting such models. In Italy, over the years, only two childhood cancer clusters have been reported in the indexed literature, both of them regarded cases of acute lymphatic leukaemia and occurred in Sardinia in the Eighties and in the area of Roma in the Nineties. A possible reason for the paucity of reports (compared, for instance, to the UK scenario) is the limited availability of health statistics.