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Colorectal cancer is one of the most incident types of cancer in the world, with almost 2 million new cases annually. In Brazil, the scenery is the same, around 41 thousand new cases were estimated in the last 3 years. This increase in cases further intensifies the interest and importance of studies related to the topic, especially using new approaches. The use of machine learning algorithms for cancer studies has grown in recent years, and they can provide important information to medicine, in addition to making predictions based on the data. In this study, five different classifications were performed, considering patients' survival. Data were extracted from Hospital Based Cancer Registries of São Paulo, which is coordinated by Fundação Oncocentro de São Paulo, containing patients with colorectal cancer from São Paulo state, Brazil, treated between 2000 and 2021. The machine learning models used provided us the predictions and the most important features for each one of the algorithms of the studies. Using part of the dataset to validate our models, the results of the predictors were around 77% of accuracy, with AUC close to 0.86, and the most important column was the clinical staging in all of them., (© 2023. The Author(s).)

Objective: To analyze the trends of cervical cancer mortality in Brazilian Southeastern states, and to compare them to Brazil and other regions between 1980 and 2020., Methods: Time series study based on data from the Sistema de Informações de Mortalidade (Brazilian Mortality Information System). Death data were corrected by proportional redistribution of deaths from ill-defined causes and cervical cancer of unspecified portion. Age-standardized and age-specific rates were calculated by screening target (25-39 years; 40-64 years) and non-target (65 years or older) age groups. Annual percentage changes (APC) were estimated by linear regression model with breakpoints. The coverage of Pap Smear exam in the Unified Health System (SUS) was evaluated between 2009 and 2020 according to age group and locality., Results: There were increases in corrected mortality rates both in 1980 and in 2020 in all regions, with most evident increments at the beginning of the series. There was a decrease in mortality nationwide between 1980-2020; however, the state of São Paulo showed a discrete upward trend in 2014-2020 (APC=1.237; 95%CI 0.046-2.443). Noteworthy is the trend increment in the 25-39 year-old group in all study localities, being sharper in the Southeast region in 2013-2020 (APC=5.072; 95%CI 3.971-6.185). Screening coverage rates were highest in São Paulo and lowest in Rio de Janeiro, with a consistent decline from 2012 onwards at all ages., Conclusions: São Paulo is the first Brazilian state to show a reversal trend in mortality from cervical cancer. The changes in mortality patterns identified in this study point to the need for reorganization of the current screening program, which should be improved to ensure high coverage, quality, and adequate follow-up of all women with altered test results.

Introduction: Brazil has high rates of caesarean sections, which has been suggested as a risk factor for acute lymphoblastic leukaemia (ALL). In addition, some pre- and postnatal conditions have been identified as relevant in the etiology of ALL., Objectives: Investigate the association of caesarean sections, pre- and postnatal conditions with childhood ALL in the State of São Paulo., Methods: Population-based case-control study including children that are below10 years old. Information on study variables was obtained through face to face interviews, through a questionnaire, and the State of São Paulo Declarations of Live Births database. The conditional and unconditional logistic regression approaches were used to calculate the odds ratio (OR) of the associations between caesarean sections, pre- and postnatal conditions with ALL, and 95 % confidence intervals (95 % CI)., Results: We observed a weak and non-statistically significant risk for ALL among children exposed to caesarean sections (unconditional logistic regression OR 1.08; 95 % CI 0.70-1.66; conditional logistic regression OR 1.21; 95 % CI 0.72-2.02), but among children under 3 years old and born through a caesarean sections, the risk of ALL was greater (unconditional logistic regression OR 1.70; 95 % CI 0.69-4.21). A negative association for ALL was observed among children with mothers who reported 12 years of schooling or more (unconditional logistic regression OR 0.34; 95 % CI 0.16-0.69)., Conclusions: We found a tenuous suggestive association between caesarean sections and childhood ALL. The mother's high level of education showed an inverse association with ALL., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

There are scarce epidemiological studies on lung cancer mortality in areas exposed to asbestos in developing countries. We compared the rates and trends in mortality from lung cancer between 1980 and 2016 in a municipality that made extensive use of asbestos, Osasco, with rates from a referent municipality with lower asbestos exposure and with the rates for the State of São Paulo. We retrieved death records for cases of lung cancer (ICD-9 C162) (ICD-10 C33 C34) from 1980 to 2016 in adults aged 60 years and older. The join point regression and age-period-cohort models were fitted to the data. Among men, there was an increasing trend in lung cancer mortality in Osasco of 0.7% (CI: 0.1; 1.3) in contrast to a mean annual decrease for Sorocaba of -1.5% (CI: -2.4; -0.6) and a stable average trend for São Paulo of -0.1 (IC: -0.3; 0.1). Similar increasing trends were seen in women. The age-period-cohort model showed an increase in the risk of death from 1996 in Osasco and a reduction for Sorocaba and São Paulo State during the same period. Our results point to a need for a special monitoring regarding lung cancer incidence and mortality in areas with higher asbestos exposure.

Objectives: To estimate the fraction of head and neck cancer (HNC) attributable to tobacco and alcohol in cities in the Midwest, Southeast and South regions of Brazil., Methods: Case-control study including 1,594 cases of HNC and 1,292 hospital controls. The association of HNC with tobacco and alcohol was estimated by the odds ratio and respective 95% confidence intervals through non-conditional logistic regression, adjusted for age, sex, schooling, consumption of fruits and vegetables, alcohol drinking (to examine the tobacco effect), and tobacco smoking (to examine the alcohol effect). The proportions of HNC attributable to tobacco and alcohol were estimated through the attributable fraction (AF) calculation. Separate estimates were made for Goiânia (Midwest), Rio de Janeiro and São Paulo (Southeast) and Pelotas and Porto Alegre (South)., Results: The HNC fraction attributable to smoking was slightly higher in Goiânia (AF = 90%) than in cities in the Southeast (AF = 87%) and South (AF = 86%). The HNC fraction attributable to the consumption of alcoholic beverages presented similar and higher results in the cities of Southeast (AF = 78%) and South (AF = 77%) than in Goiânia (AF = 62%)., Conclusion: The HNC fractions attributable to smoking were more expressive than for alcohol consumption. Although with discrete distinctions between them, the AFs to tobacco smoking and alcohol consumption in HNC observed in the cities of these three Brazilian regions were similar to those obtained in Latin America studies, but they were higher than in other parts in the world.

Background: The role of human papillomavirus (HPV) on head and neck squamous cell carcinoma (HNSCC) survival in regions with low HPV prevalence is not yet clear. We evaluated the HPV16 infection on survival of HNSCC Brazilian patient series., Methods: This cohort comprised 1,093 HNSCC cases recruited from 1998 to 2008 in four Brazilian cities and followed up until June 2009. HPV16 antibodies were analyzed by multiplex Luminex assay. In a subset of 398 fresh frozen or paraffin blocks of HNSCC specimens, we analyzed for HPV16 DNA by L1 generic primer polymerase chain reaction. HNSCC survival according to HPV16 antibodies was evaluated through Kaplan-Meier method and Cox regression., Results: Prevalence of HPV16 E6 and E6/E7 antibodies was higher in oropharyngeal cancer than in other head and neck tumor sites. HPV16 DNA positive in tumor tissue was also higher in the oropharynx. Seropositivity for HPV16 E6 antibodies was correlated with improved HNSCC survival and oropharyngeal cancer. The presence of HPV16 E6/E7 antibodies was correlated with improved HNSCC survival and oropharyngeal cancer survival. The death risk of oropharyngeal squamous cell carcinoma patients HPV16 E6/E7 antibodies positive was 78 % lower than to those who test negative., Conclusion: Oropharyngeal squamous cell carcinoma is less aggressive in the HPV16 E6/E7 positive serology patients. HPV16 E6/E7 antibody is a clinically sensible surrogate prognostic marker of oropharyngeal squamous cell carcinoma.

Objective: To analyze studies that evaluated the role of infections as well as indirect measures of exposure to infection in the risk of childhood leukemia, particularly acute lymphoblastic leukemia., Methods: A search in Medline, Lilacs, and SciELO scientific publication databases initially using the descriptors "childhood leukemia" and "infection" and later searching for the words "childhood leukemia" and "maternal infection or disease" or "breastfeeding" or "daycare attendance" or "vaccination" resulted in 62 publications that met the following inclusion criteria: subject aged ≤ 15 years; specific analysis of cases diagnosed with acute lymphoblastic leukemia or total leukemia; exposure assessment of mothers' or infants' to infections (or proxy of infection), and risk of leukemia., Results: Overall, 23 studies that assessed infections in children support the hypothesis that occurrence of infection during early childhood reduces the risk of leukemia, but there are disagreements within and between studies. The evaluation of exposure to infection by indirect measures showed evidence of reduced risk of leukemia associated mainly with daycare attendance. More than 50.0% of the 16 studies that assessed maternal exposure to infection observed increased risk of leukemia associated with episodes of influenza, pneumonia, chickenpox, herpes zoster, lower genital tract infection, skin disease, sexually transmitted diseases, Epstein-Barr virus, and Helicobacter pylori ., Conclusions: Although no specific infectious agent has been identified, scientific evidence suggests that exposure to infections has some effect on childhood leukemia etiology.

Background: Epidemiological studies have identified increased risks of leukemia in children living near power lines and exposed to relatively high levels of magnetic fields. Results have been remarkably consistent, but there is still no explanation for this increase. In this study we evaluated the effect of 60 Hz magnetic fields on acute lymphocytic leukemia (ALL) in the State of São Paulo, Brazil., Methods: This case-control study included ALL cases (n=162) recruited from eight hospitals between January 2003 and February 2009. Controls (n=565) matched on gender, age, and city of birth were selected from the São Paulo Birth Registry. Exposure to extremely low frequency magnetic fields (ELF MF) was based on measurements inside home and distance to power lines., Results: For 24h measurements in children rooms, levels of ELF MF equal to or greater than 0.3microtesla (μT), compared to children exposed to levels below 0.1 μT showed no increased risk of ALL (odds ratio [OR] 1.09; 95% confidence interval [95% CI] 0.33-3.61). When only nighttime measurements were considered, a risk (OR 1.52; 95% CI 0.46-5.01) was observed. Children living within 200 m of power lines presented an increased risk of ALL (OR 1.67; 95% CI 0.49-5.75), compared to children living at 600 m or more of power lines. For those living within 50 m of power lines the OR was 3.57 (95% CI 0.41-31.44)., Conclusions: Even though our results are consistent with the small risks reported in other studies on ELF MF and leukemia in children, overall our results do not provide support for an association between magnetic fields and childhood leukemia, but small numbers and likely biases weaken the strength of this conclusion., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: A higher burden of head and neck cancer has been reported to affect deprived populations. This study assessed the association between socioeconomic status and head and neck cancer, aiming to explore how this association is related to differences of tobacco and alcohol consumption across socioeconomic strata., Methods: We conducted a case-control study in São Paulo, Brazil (1998-2006), including 1017 incident cases of oral, pharyngeal and laryngeal cancer, and 951 sex- and age-matched controls. Education and occupation were distal determinants in the hierarchical approach; cumulative exposure to tobacco and alcohol were proximal risk factors. Outcomes of the hierarchical model were compared with fully adjusted ORs., Results: Individuals with lower education (OR 2.27; 95% CI 1.61 to 3.19) and those performing manual labour (OR 1.55; 95% CI 1.26 to 1.92) had a higher risk of disease. However, 54% of the association with lower education and 45% of the association with manual labour were explained by proximal lifestyle exposures, and socioeconomic status remained significantly associated with disease when adjusted for smoking and alcohol consumption., Conclusions: Socioeconomic differences in head and neck cancer are partially attributable to the distribution of tobacco smoking and alcohol consumption across socioeconomic strata. Additional mediating factors may explain the remaining variation of socioeconomic status on head and neck cancer.

Cancers of the upper aerodigestive tract (UADT: oral cavity, oropharynx, hypopharynx, larynx, esophagus) have high incidence rates all over the world and they are especially frequent in some parts of Latin America. In this study, we have evaluated the role of the consumption of maté, a hot herb-based beverage, based on 1168 UADT squamous-cell carcinoma cases and 1,026 frequency-matched controls enrolled from four centers in Brazil and Argentina. The effect of maté drinking on the risk of head-and-neck cancers was borderline significant. A significant effect was observed only for cancer of the esophagus (OR 3.81 (95% CI 1.75-8.30)). While duration of maté drinking was associated with the risk of all UADT cancers, the association with cumulative maté consumption was restricted to esophageal cancer (p-value of linear trend 0.006). The analyses of temperature at which maté was drunk were not conclusive. The increased risk associated with maté drinking was more evident in never-smokers and never-alcohol drinkers than in other individuals. Our study strengthens the evidence of an association between maté drinking and esophageal cancer; the hypothesis of an association with other UADT cancers remains to be clarified.

The objective of this paper was to assess sex and socioeconomic inequalities in lung cancer mortality in two major cities of Europe and South America. Official information on mortality and population allowed the estimation of sex- and age-specific death rates for Barcelona, Spain and São Paulo, Brazil (1995-2003). Mortality trends and levels were independently assessed for each city and subsequently compared. Rate ratios assessed by Poisson regression analysis addressed hypotheses of association between the outcome and socioeconomic covariates (human development index, unemployment and schooling) at the inner-city area level. Barcelona had a higher mortality in men (76.9/100,000 inhabitants) than São Paulo (38.2/100,000 inhabitants); although rates were decreasing for the former (-2%/year) and levelled-off for the latter. Mortality in women ranked similarly (9.1 for Barcelona, 11.5 for São Paulo); with an increasing trend for women aged 35-64 years (+7.7%/year in Barcelona and +2.4%/year in São Paulo). The socioeconomic gradient of mortality in men was negative for Barcelona and positive for São Paulo; for women, the socioeconomic gradient was positive in both cities. Negative gradients indicate that deprived areas suffer a higher burden of disease; positive gradients suggest that prosmoking lifestyles may have been more prevalent in more affluent areas during the last decades. Sex and socioeconomic inequalities of lung cancer mortality reinforce the hypothesis that the epidemiologic profile of cancer can be improved by an expanded access to existing technology of healthcare and prevention. The continuous monitoring of inequalities in health may contribute to the concurrent promotion of well-being and social justice.

Purpose: Oral and oropharyngeal tumor resection may be associated with disfigurement and dysfunctions that affect essential domains of life. This study aimed at assessing the immediate impact of primary surgery on the health-related quality of life for these patients., Patients and Methods: Forty-seven patients with squamous cell carcinoma of the lips, oral cavity, or oropharynx, and undergoing treatment in the head and neck surgery center of a large general hospital in the city of São Paulo, Brazil, from October 2005 to September 2006, completed the University of Washington Quality of Life questionnaire pre- and postoperatively (before hospital discharge). A paired t test evaluated differences between assessments; Poisson regression estimated ratios of ratings attributed to each domain (pain, appearance, activity, recreation, swallowing, chewing, speech, shoulder pain, taste, saliva, mood, and anxiety) per patient stratified by sociodemographic, clinical, and behavioral characteristics., Results: The immediate impact of surgery on health-related quality of life corresponded to a 31.1% reduction in the overall rating. The most affected domains were chewing (-73.5%), taste (-61.4%), swallowing (-57.3%), speech (-46.0%), and pain (-42.3%). Anxiety (+65.5%) was the sole domain that improved immediately after surgery. Comparisons involving subgroups of patients indicated that different clinical conditions (regional metastasis, tumor size, and location) were not associated with discrepant health-related quality of life immediately after surgery., Conclusions: The routine pre- and postoperative assessment of health-related quality of life may contribute to evaluate treatment effectiveness, which would otherwise rely exclusively on assessing end-point results such as survival and tumor relapse. This information is relevant to attenuate the prejudicial impact of surgery on the physical and psychosocial functioning of patients.

Objective: To assess the association between oral health and hygiene practices and oral cancer., Methods: Hospital-based case-control study in the metropolitan area of São Paulo, southeastern Brazil, from 1998 to 2002. A total 309 patients with squamous cell carcinoma of the mouth and the pharynx and 468 controls matched by sex and age were included in the study. Cases were recruited in seven reference hospitals and controls were selected in five out of the seven participating hospitals. Detailed information on smoking, alcohol consumption, schooling, oral health status and hygiene practices were obtained through interviews. Odds ratios (OR) and 95% confidence intervals (95% CI), adjusted by sex, age, schooling, smoking, alcohol consumption as well as the variables oral health status and hygiene practices were estimated using unconditional logistic regression analyses., Results: The use of complete dental prosthesis was not associated with oral cancer but regular gum bleeding showed a strong association (OR 3.1; 95% CI 1.2-7.9). Those who never attended a dental visit were more likely to have oral cancer (OR 2.5; 95% CI 1.3-4.8). Daily mouthwash use showed a stronger association to pharynx (OR 4.7; 95% CI 1.8-12.5) than mouth cancer (OR 3.2; 95% CI 1.6-6.3)., Conclusions: Gum bleeding, no dental care, and daily mouthwash use were factors associated with oral cancer regardless of tobacco and alcohol consumption.

Objective: To evaluate the results of the 2004 oral cancer prevention and early diagnosis program carried out in conjunction with the annual flu vaccination campaign for the elderly in the state of São Paulo, Brazil., Methods: Data concerning the follow-up of patients referred for diagnostic investigation of soft tissue lesions identified on visual inspection were collected from the reports issued by the State Health Department/Oral Health Technical Center. The following two characteristics were evaluated as indicators of the program's effectiveness: (1) the number of people whose problem was resolved at the primary care level or in referral services and (2) the number of persons with a confirmed diagnosis of oral cancer. The following indicators were used to assess program ineffectiveness: (1) patients not appearing at the referral unit, (2) inability of the primary care services to resolve the problem, and (3) the absence of follow-up information on patients., Results: In 2004, 238 087 people >/= 60 years old were examined, corresponding to 6.8% of the state population in this age group (3 494 555 people). The program was carried out in 23 of the state's 24 health regions. However, only 8 of the regions recorded follow-up information. Of the 5 280 people in the 8 regions who were referred for diagnostic investigation of soft tissue lesions, 60.5% had their problem resolved, 0.5% (26 cases) had a confirmed diagnosis of oral cancer, and 22.5% did not have the diagnostic investigation completed. For 16.5% of the cases referred for further study, there was no information available concerning follow-up and outcomes., Conclusions: The oral cancer prevention and early diagnosis program was ineffective, given the lack of monitoring of results in most parts of the state of São Paulo, and the high proportion of patients whose soft tissue lesion was not resolved. The usefulness of continuing the program in future years needs to be evaluated.

Reports of uterine cancer deaths that do not specify the subsite of the tumor threaten the quality of the epidemiologic appraisal of corpus and cervix uteri cancer mortality. The present study assessed the impact of correcting the estimated corpus and cervix uteri cancer mortality in the city of São Paulo, Brazil. The epidemiologic assessment of death rates comprised the estimation of magnitudes, trends (1980-2003), and area-level distribution based on three strategies: i) using uncorrected death certificate information; ii) correcting estimates of corpus and cervix uteri mortality by fully reallocating unspecified deaths to either one of these categories, and iii) partially correcting specified estimates by maintaining as unspecified a fraction of deaths certified as due to cancer of "uterus not otherwise specified". The proportion of uterine cancer deaths without subsite specification decreased from 42.9% in 1984 to 20.8% in 2003. Partial and full corrections resulted in considerable increases of cervix (31.3 and 48.8%, respectively) and corpus uteri (34.4 and 55.2%) cancer mortality. Partial correction did not change trends for subsite-specific uterine cancer mortality, whereas full correction did, thus representing an early indication of decrease for cervical neoplasms and stability for tumors of the corpus uteri in this population. Ecologic correlations between mortality and socioeconomic indices were unchanged for both strategies of correcting estimates. Reallocating unspecified uterine cancer mortality in contexts with a high proportion of these deaths has a considerable impact on the epidemiologic profile of mortality and provides more reliable estimates of cervix and corpus uteri cancer death rates and trends.

Objective: To investigate cancer deaths among rubber industry workers according to company size., Methods: This historical cohort study included 9,188 male workers, engaged as members of a workers' union in São Paulo, Southeastern Brazil, between 1975 and 1985, alive in January 1990 and followed until the end of 2000. Overall and specific cancer deaths were compared within the cohort, with subjects stratified according to company size and economic activity, sector of work, and worker qualification. Risk set assessment and conditional logistic regression were used to estimate relative risks, adjusted for age, time since first job, and duration of employment in the rubber industry., Results: When compared to employees of larger companies, workers employed in small companies showed greater risk of death due to any type of cancer (RR=2.33, 95% CI: 0.90-6.03), stomach tumors (RR=3.47; 95% CI: 2.57-4.67), and upper aero-digestive tract tumors (RR=2.49; 95% CI: 1.78-3.48). Risk of death was greater among workers employed in maintenance (RR=2.23; 95% CI: 0.73-6.76); expedition, storage and transportation (RR=2.97; 95% CI: 0.77-11.38); and production (RR=3.51; 95% CI: 1.07-11.57), when compared to workers engaged in clerical work and support activities., Conclusions: Our results provide further evidence for an increased risk of stomach and upper aero-digestive tract tumors--and possibly of all types of cancer--among rubber industry workers employed in small companies when compared to employees of larger companies.

Genomics is expanding the horizons of epidemiology, providing a new dimension for classical epidemiological studies and inspiring the development of large-scale multicenter studies with the statistical power necessary for the assessment of gene-gene and gene-environment interactions in cancer etiology and prognosis. This paper describes the methodology of the Clinical Genome of Cancer Project in São Paulo, Brazil (CGCP), which includes patients with nine types of tumors and controls. Three major epidemiological designs were used to reach specific objectives: cross-sectional studies to examine gene expression, case-control studies to evaluate etiological factors, and follow-up studies to analyze genetic profiles in prognosis. The clinical groups included patients' data in the electronic database through the Internet. Two approaches were used for data quality control: continuous data evaluation and data entry consistency. A total of 1749 cases and 1509 controls were entered into the CGCP database from the first trimester of 2002 to the end of 2004. Continuous evaluation showed that, for all tumors taken together, only 0.5% of the general form fields still included potential inconsistencies by the end of 2004. Regarding data entry consistency, the highest percentage of errors (11.8%) was observed for the follow-up form, followed by 6.7% for the clinical form, 4.0% for the general form, and only 1.1% for the pathology form. Good data quality is required for their transformation into useful information for clinical application and for preventive measures. The use of the Internet for communication among researchers and for data entry is perhaps the most innovative feature of the CGCP. The monitoring of patients' data guaranteed their quality.

Objective: To develop a population-based matrix of job-exposure to crystalline silica in Brazil and to estimate its validity., Methods: An epidemiologist and an industrial hygienist developed a matrix of job-exposure in four stages: coding of occupation variable; coding of industry variable; consensual exposure classification between researchers; and estimate of registered workforce in 1995 for each level of exposure. The cross-tabulation of the variables industry (25 columns) and occupation (347 lines) resulted in 8,675 cells, classified according to silica exposure in four levels: non-exposed, possibly exposed, probably exposed, and definitively exposed. For validating the job-exposure matrix, five industries (mining and quarrying, construction, foundry, management of technical personal and textiles), were re-coded according to exposure by external experts. Reliability of the study and external experts was evaluated by agreement measured using kappa analysis., Results: The job-exposure matrix showed high coding agreement, ranging from 64.0% for foundry to 94.0% for mining. Kappa analysis showed good agreement in mining (0.9), and low or average for other sectors (ranging from 0.1 to 0.5). High specificity was found in foundry (86.5%) and mining (100.0%). Construction had 56% specificity., Conclusions: The study job-exposure matrix showed good accuracy and seems to be appropriate for estimating silica exposure among Brazilian workers.

The city of São Paulo exhibits one of the highest incidences of laryngeal cancer in world and Brazil presents remarkable occurrence, compared with other Latin American countries. Around 8,000 new cases and 3,000 deaths by laryngeal cancer occur annually in the Brazilian population. In the city of São Paulo, incidence rates for laryngeal cancer among males have been decreasing since the late 1980s while, among females, the rates have shown a stable trend. This phenomenon is probably the expression of changes in gender behavior related to tobacco smoking. Several risk factors are involved in the genesis of laryngeal cancer. The most important are tobacco smoking and alcohol intake, but occupational hazards have also been associated with the disease, such as asbestos, strong inorganic acids, cement dust and free crystalline silica. Additionally, salted meat and total fat intake have been linked to elevated risk of laryngeal cancer. Conversely, several studies have confirmed that fruits, raw leaf vegetables and legumes protect against this cancer. Some researchers have postulated a possible association between laryngeal squamous cell carcinoma and human papilloma virus (HPV), but this is not universally accepted. Gastroesophageal reflux disease is weakly, but consistently correlated with laryngeal cancer. Familial cancer clusters, particularly of head and neck tumors, seem to increase the risk of laryngeal cancer. Some genetic polymorphisms, such as of genes that code for xenobiotic-metabolizing enzymes, have shown elevated risk for laryngeal cancer according to recent studies. Public health policies regarding the control of tobacco smoking and alcohol consumption, and also surveillance of carcinogen exposure in occupational settings, could have an impact on laryngeal cancer. No proposals for screening have been recommended for laryngeal cancer, but one diagnostic goal should be to avoid treatment delay when suspected symptoms have been observed.

A study was carried out on the occurrence of oral and pharynx cancer among populations living in five Brazilian geographic regions, by using incidence and mortality rates and trends. Information on survival was also analyzed. Complementary information regarding prevalence of the disease risk factors has been supplied in the attempt to establish some etiological connections with the incidence and mortality observed. Two clear patterns for the occurrence of oral and pharyngeal cancer have been detected: a pattern for the north (including the northern, northeastern and midwestern regions, which are the poorest ones) and a pattern for the south (including the southern and southeastern regions). The southern pattern revealed incidence rates higher than 15 per 100,000 among males, and the northern pattern displayed lower rate levels. Similarly, mortality rates in the south were higher than three per 100,000 and the northern pattern was characterized by lower rates. Other cancers linked to tobacco smoking, such as esophagus, larynx, lung and bladder cancer kept the same pattern of incidence and mortality rates related to oral and pharyngeal cancer in males per region. Information on survival of patients with oral and pharyngeal cancer was very restricted in Brazil, thus hindering the survival analysis per region, but the studies conducted allowed to conclude that the majority of diagnoses were conducted in advanced stages of the disease and implied the low 5-year survival rate observed in Brazil. Tongue tumors displayed the worst survival rates. The southern region shares specific risk factors involved in the oral and pharyngeal cancer present in the Argentinean and Uruguayan populations, namely heavy tobacco smoking and alcohol consumption, as well as high intake of charcoal-grilled red meat and mate. In addition to these risks, part of the oral and pharyngeal cancer registered in Brazil might be linked to a few factors present among people with low life standards, including poor oral hygiene and nutrition.

Context: Around 90% of lung cancer worldwide is attributable to cigarette smoking, although less than 20% of cigarette smokers develop lung cancer. Other factors such as diet, chronic lung diseases, occupation and possibly environmental agents also contribute to this cancer. Genetic factors seem to play a role in lung cancer, but the precise characteristics influencing lung cancer susceptibility are not known, since genetic factors are easily obscured by the strong environmental determinants of lung cancer, particularly smoking., Objective: To estimate the effect that cancer occurrence among first-degree relatives has on the risk of lung cancer., Design: Hospital-based case-control study., Setting: The metropolitan region of São Paulo, Brazil., Participants: 334 incident lung cancer cases and 578 controls matched by hospitals., Main Measurements: By means of a structured questionnaire, cases and controls were interviewed about cancer occurrence in first-degree relatives, tobacco smoking, exposure to passive smoking, occupation, migration and socioeconomic status. Non-conditional logistic regression was used to calculate the risk of familial cancer aggregation, the effect of cancer in first-degree relatives and smoking in conjunction, and for controlling confounders., Results: The adjusted odds ratio (OR) revealed a slight, but not statistically significant, excess risk of lung cancer for subjects with a history of lung cancer in relatives (OR 1.21; 95% confidence interval [CI] 0.50 - 2.92). The same was found among those with a history of other tobacco-related cancers in relatives (OR 1.36; 95% CI 0.87 - 2.14). A step gradient effect was observed regarding lung cancer risk, in accordance with increases in the number of pack-years of cigarette consumption. An interaction between familial cancer aggregation and tobacco smoking was detected., Conclusions: A mildly elevated risk of lung cancer among persons with a positive history of lung and other tobacco-related cancers was observed. The finding of an interaction between the variables of familial cancer aggregation and smoking suggests that familial cancer aggregation could be considered as a marker of susceptibility, increasing the risk of lung cancer among smokers. These results improve our knowledge of lung carcinogenesis and can guide future cancer genetic studies.

During the last two decades, incidence rates of occupational accidents have been decreasing in Brazil. Mortality has also decreased, but not as sharply as incidence. Changes in reporting of occupational accidents have been the main argument used to explain such trends. This time-series study covering occupational accidents from 1970 to 1995 clearly shows the link between occupational accidents and social and economical determinants. Comparing 14 Brazilian States, a positive linear regression (r=0.80) was detected between proportion of workers in industrial production and accidents. In the 1980s, Brazil's economic recession led to an increase in unemployment. The decline in industrial jobs - those with a higher risk of accidents ( was accented by the restructuring of production and increased use of computer and robotics technologies in various manufacturing sectors. The result was a heavy shift of the work force from industry to commerce and services - jobs entailing lower risk of accidents. These factors influenced trends in occupational accidents in Brazil during this 25-year period.

Objectives: This study estimated the risk of occupational exposure for lung cancer in the metropolitan region of São Paulo, the largest urbanized and industrialized area in Brazil., Methods: In this hospital-based case-referent study of 398 cases and 860 referents, the cases were matched to referents according to age, gender, and hospital and personally interviewed for information on lifetime job history, smoking habits, passive smoking exposure, cancer in relatives, socioeconomic status, and migratory history. The analysis concerned industrial titles and occupational categories. With the use of a job-exposure matrix, exposure to asbestos, polynuclear aromatic hydrocarbons, arsenic, dust, nickel and chromium was assessed., Results: For the men in the 56 industrial and 122 occupational categories examined, an excess risk of lung cancer was found in the machinery industry [odds ratio (OR) 1.62, 95% confidence interval (95% CI) 1.02-2.55). In pottery manufacturing the risk (OR 2.21, 95% CI 1.00-4.87) was increased for workers exposed > or = 10 years (OR 6.43, 95% CI 1.12-37.01). Textile workers employed for > or = 10 years with a latency of > or = 40 years had an elevated risk (OR 21.93, 95% CI 1.96-245.0). In the analysis using the job-exposure matrix no risk was detected for the specific lung cancer carcinogens examined. For the women, no significantly elevated risk was observed., Conclusions: The results of this study revealed risks of lung cancer for men in the machinery industry and for pottery and textile workers with long-term exposure.

In a hospital-based case-control study, 316 lung cancer cases and 536 controls were interviewed for their occupational, smoking, passive smoking, cancer in the family and residential histories as well as social economic status, by trained interviewers, using a standardized questionnaire. Cases and controls were matched by hospital, sex and age. The study was carried out between 1st July 1990 and 31st January 1991 in 14 hospitals in the Metropolitan Region of S. Paulo, the most highly industrialized and urbanized region in Brazil. Score criteria were developed for the ordering of the individuals of the study by occupational exposure to know carcinogens to the lung, in order to evaluate this exposure during the occupational life of each person. The criteria accumulated information on exposure to carcinogens as regards type, sector of work and time in each employment. The unconditional logistic regression analysis showed an odds ratio of 1.97 (95% IC: 1.52 to 2.55) for the highest exposure group. This result showed that workers linked to the production sectors of several industries have about twice the risk of developing lung cancer as workers involved in non-industrial activities.

The epidemiological approach to occupational accidents and diseases adopted in Brazil is inadequate for many reasons, among them being: 1) the fact that only employers may notify work accidents, thus permitting notorious undernotification of these occupational hazards; 2) the available information does not permit a better understanding of the causal relationship between work accidents and diseases; 3) the official policy exists only for purposes of insurance compensation. The official documents for occupational disease and accident registration are the CTA (Work accident report) and FTA (Casualty treatment card). The Worker's Health Program of SUDS-R-6 proposed, in October, 1988 a method for the codification, registration in a micro-computer data bank and analysis of this information, based on the records presently in use (CAT) for public health service planning and accident prevention purposes. The major interest was in identifying the most common types of accidents in the region and the work environments in which they most frequently occur. The target population were the workers who attended the health units lisenced to deal with work accidents and diseases, in the Northern region of S. Paulo City. The data presented below refer to the months of October, November and December, 1988, the first three months of the project. During that period a total of 2,339 accidents were registered. They were classified as: typical work accidents - 87%: commuting accidents which occurred between the home and the work-place--18% and work diseases (only 2 cases). The majority of workers (50%) were between 25 and 45 years of age, approximately 7% were under 18. Male workers represented 83.2% of accident cases.(ABSTRACT TRUNCATED AT 250 WORDS)

A case-control study was carried out in the Metropolitan Region of São Paulo, Brazil, to determine the protection against tuberculous meningitis conferred by BCG vaccination to children aged less than 5 years. The BCG vaccination coverage in the study area was about 88%. A total of 72 tuberculous meningitis patients were studied as well as 505 neighbourhood and 81 hospital controls. Analysis of the data using a conditional logistic regression for matched case-control studies indicated that the efficacy of BCG was similar for both groups of controls, that for neighbourhood controls (84.5%) being slightly greater than that for hospital controls (80.2%). No significant interactions were found between vaccination status and sex, age, or socioeconomic status.