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Background. Recent epidemiologic studies have suggested changing patterns of lung cancer incidence by histologic type. The observed time trends have been attributed to a change in the rate of cigarette smoking, changes in exposure to new environmental carcinogens, and changes in the criteria for the histopathologic diagnosis of lung cancer. The current study was designed to examine the incidence patterns of lung cancer by histologic type in Connecticut and to use this information to project the future trend of the disease in this population. Methods. This study was based on all the lung cancer cases reported to the Connecticut Tumor Registry between 1960 and 1989. On the basis of this data set, crude and age-adjusted incidence rates of lung cancer were calculated by histologic type for each sex. The age-specific incidence rates are presented by calendar year and cohort year of birth. A regression model was used to identify birth cohort, period, and age as determinants of the observed time trends. Results. For the overall age-adjusted incidence rates, squamous cell carcinoma and small cell carcinoma have stabilized in men, whereas they are still increasing in women. The incidence of adenocarcinoma has been increasing in both men and women, but there has been a much sharper incidence among females since the mid-1970s. An examination of age-specific incidence rates by birth cohort and the results from age-period-cohort modeling indicate that incidences of all three major histologic types of lung cancer in the recent birth cohorts either have started decreasing (squamous cell carcinoma) or shown a clear reduction in the rate of increase (adenocarcinoma and small cell carcinoma). This study, however, did not indicate an increase of bronchoalveolar lung carcinoma, which was reported by other clinically based studies. Conclusion. While the overall age-adjusted incidence rates showed different incidence patterns for different histologic types of lung cancer, a decreasing or stabilized rate for all three major histologic types of lung cancer was observed in recent birth cohorts in both males and females. The observed incidence pattern is consistent with smoking trends over time including changes in smoking prevalence and the consumption of low tar and filter cigarettes. It is expected that if the current trend in tobacco smoking continues and if there are no major changes in other risk factors for lung cancer, a forthcoming stabilization or decrease in the rate of lung cancer incidence for all major histologic types (including adenocarcinoma) in both sexes in Connecticut could be anticipated.

Background. Adenocarcinoma of the gastric cardia has been be increasing in Connecticut, and the risk factors responsible for the increasing incidence are unknown. This study examined the incidence pattern of adenocarcinoma of the gastric cardia and distal stomach in Connecticut during the past decades and identified components of birth cohort, period, and age as determinants of the observed time trends by regression modeling. Methods. This study was based on all histologically confirmed incident cases of gastric adenocarcinoma reported to the Connecticut Tumor Registry between 1955 and 1989. Stomach cancers were grouped into cancers of the gastric cardia, distal stomach, or unknown/unspecified subsite. Age-adjusted incidence rates were calculated by the direct method standardized to the 1970 United States population. A regression model was used to identify birth cohort, period, and age as determinants of the observed time trends. Results. The results indicated that the incidence rate of adenocarcinoma of the cardia is increasing, particularly in white males, whereas adenocarcinoma of the distal stomach is now decreasing in both sexes in Connecticut. Regression modeling suggests that the increase of adenocarcinoma of the cardia may be explained partly by a birth cohort phenomenon. Conclusion. There is little information regarding the risk factors that might be responsible for the observed increasing trend for adenocarcinoma of the cardia, although smoking, alcohol intake, retinol intake, and hiatal hernia have been associated with an increased risk of adenocarcinoma of the cardia or gastric cancer. Considering the different epidemiologic features of adenocarcinoma of the cardia and distal stomach, future analytic studies should separate cancer of the gastric cardia and cancer of the distal stomach in searching for etiologic factors.

Background. During the past decades, there have been reports of increases in the incidence and mortality rates due to non-Hodgkin lymphoma (NHL) in many parts of the world. The risk factors responsible for the increasing incidence are largely unknown. This study provided an overview of the incidence pattern of NHL in Connecticut and generated hypotheses for additional investigation. Methods. This study was based on all the NHL cases reported to the Connecticut Tumor Registry (CTR) between 1935 and 1988. Crude, age-adjusted, and age-specific incidence rates of NHL were calculated for each sex. Age-adjusted incidence rates were calculated by the direct method standardized to the 1970 United States standard million population. The data are presented by calendar year and cohort year of birth to examine the secular trends and birth cohort effects. Racial information was not coded before 1957 and is of uncertain validity until the early 1970s; therefore, racial analysis was restricted to 1970-1988. Analyses by histologic subtypes and by anatomic sites were restricted to the last 3 decades (1960-1988) because more accurate classification systems were used during this time. Results. A total of 11,326 newly diagnosed cases of NHL were included in the study. Of them, 5866 (52%) were diagnosed in men and 5460 (48%) were diagnosed in women. The study results indicated that the incidence rate of NHL has been increasing during the past decades for men and women, whites and blacks, nodular NHL and diffuse NHL, disease originating from lymph nodes and disease originating from other sites, and in all age groups, especially the older age groups. Birth cohort examination did not show any indication of a decline or levelling off in incidence rates among recent birth cohorts. Age-specific incidence rates in both sexes suggested that the rates increase with age, with a sharp increase beginning at 50 years of age and peaking at 80 years of age. Men had a 30% higher incidence rate than women, and whites had approximately 1.5 times the age-adjusted incidence rate of blacks. Conclusions. The results indicated that the incidence rate of NHL has been increasing in Connecticut during the past decades and is likely to continue to rise in the coming years. Analytical epidemiologic studies are needed to examine the risk factors that might account for the increase in NHL. Cancer 1992; 70:840-849.

For a few years in the 1980s, United States mortality rates suggested a plateau in the long-term increase for malignant melanoma. However, temporary plateaus in the increase of the age-adjusted rate by year of death have occurred in previous decades, only to be followed by a continued upward increase, with a long-term rise of about 2% per year. To determine whether a cessation in the long-term increase might be in progress, death rates were analyzed by year of birth, age at death, and year of death: (1) the long-term patterns of change are best described by birth cohort rather than by time period of death, indicating that analyses by a year of birth are key to a better understanding of the long-term trends; (2) in both men and women, evidence for a change in slope begins among those born in the early 1930s; (3) the decline in the rates begins among women born since the early 1930s and among men born since the early 1950s: the slope for men is -0.2661 (95% confidence limits [CL] = -0.380 to -0.152), and, for women, the slope is -0.02354 (95% CL = -0.041 to -0.005); (4) long-term Connecticut and US mortality trends were similar in pattern and direction, and long-term Connecticut incidence rates showed a persistent increase through the 1955 to 1965 birth cohorts. These analyses suggest a persistent cessation in the long-term increase and a downward trend in death rates from this cancer. Cancer 1992; 69:1714-1720.

Epidemiologic studies have recently related benzene hexachloride (BHC) to breast carcinoma risk. Experimental studies have also shown that β-BHC is weakly estrogenic, hence supporting the alleged association. By directly comparing β-BHC levels in breast adipose tissue from incident breast carcinoma cases and controls, this study examined the hypothesis that exposure to β-BHC increases the risk of breast carcinoma in females. A total of 490 Connecticut women (304 cases and 186 controls) were enrolled in the study during the period 1994–1997. Cases were patients ages 40–79 years with histologically confirmed incident primary breast carcinoma. Controls were patients with histologically confirmed incident benign breast disease. Breast adipose tissue was collected and analyzed for BHC isomers. A linear logistic regression model was used to adjust for potential confounders in estimating the association of exposure with disease. No significant differences in breast adipose tissue levels of β-BHC were observed between the cases and their controls overall, nor by menopausal status or estrogen and progesterone receptor status of the breast carcinoma cases. A nonsignificant reduced risk was observed among all subjects and among pre- and postmenopausal women when the highest quartile was compared with the lowest. Parous women with higher β-BHC levels, regardless of lactation status, had a nonsignificantly reduced breast carcinoma risk, whereas a nonsignificantly increased risk was observed among nulliparous women with higher β-BHC levels, based on very few study subjects. The results of this study do not support the hypothesis that increasing adipose tissue levels of β-BHC are associated with an increased risk of breast carcinoma in females. Cancer 1999;85:2212–8. © 1999 American Cancer Society.