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S T Mayne

Publications and source records attributed to S T Mayne.

14 recordsLinked to original sources
PubMed1992

Time trends of non-Hodgkin's lymphoma: are they real? What do they mean?

Factors that need to be considered in the analysis of time trends in disease incidence are age, year of diagnosis, and birth cohort. When these are included in a log-linear model, a nonidentifiability problem arises from the linear dependence among these three time factors so that only specified functions of the parameters can be unambiguously determined. One of these invariant functions is the drift or the sum of the period and cohort trend. Non-Hodgkin's lymphoma incidence rates from Connecticut for the period 1935-1989 were analyzed for males and females. In addition to an age effect, both period and cohort significantly improved the fit of the model. The estimated drift shows that there has been a 10.3% increase in risk every 5 years since 1965 for females and 9.2% for males. It is unlikely that a trend of this magnitude can be attributed entirely to data artifact.

Adult↗
PubMed1992

Epidemiology of non-Hodgkin lymphoma in Connecticut. 1935-1988.

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.

Adult↗
PubMed1992

Time trend and age-period-cohort effects on incidence of esophageal cancer in Connecticut, 1935-89.

The purpose of this study was to examine the incidence pattern of esophageal cancer in Connecticut (USA) during the past decades, and to identify components of birth cohort, period, and and age as determinants of the observed time trends by regression modelling. This study is based on all of the esophageal cancer cases reported to the Connecticut Tumor Registry between 1935 and 1989. A total of 6,310 incident cases were included. Results indicate that among males, the overall age-adjusted incidence rate of esophageal cancer increased after 1935 and peaked between 1955 and 1959. Since then, incidence rates have been relatively stable. Among females, the overall esophageal cancer rate has not changed markedly since 1935. Analysis by histologic type indicates that the incidence rate of squamous cell carcinoma has been declining in this population; adenocarcinoma, however, showed a continuous increase. A fivefold increase among males and a threefold increase among females were observed for adenocarcinoma of the esophagus between 1970 and 1989. If cancers of the esophagus and gastric cardia are considered together, the incidence rate of adenocarcinoma exceeds that of squamous cell carcinoma among males during 1985-89. The observed increasing trend for adenocarcinoma of the esophagus is mainly from cancers arising in the lower third of the esophagus and primarily among Whites, especially White males. The results from regression modeling indicate that both period and birth cohort may have contributed to the observed increasing trend, and adenocarcinoma of the esophagus is likely to increase continuously in this population in the coming years.

Adenocarcinoma↗
PubMed1991

Dietary retinol: prevention or promotion of carcinogenesis in humans?

A number of epidemiologic studies have found that 'vitamin A' is associated with a reduced risk for human cancers. Dietary vitamin A indices reflect intake of several compounds in the diet including retinol and pro-vitamin A carotenoids such as beta-carotene, and recent cancer epidemiology studies have attempted to distinguish effects of retinol from those of beta-carotene. While beta-carotene has been associated consistently with a reduced risk for a number of human cancers, particularly epithelial cancers, retinol is generally found to be unassociated with, or positively associated with, risk for many cancers. An apparent enhancement of carcinogenesis has been observed in numerous studies, particularly for cancer of the esophagus, oral cavity, pharynx, larynx, stomach, colon, and rectum. While this finding could be artifactual, experimental studies in animals as well as mechanistic considerations suggest that this effect deserves serious consideration. As discussed in this article, an apparent enhancement of carcinogenesis could be related to an ethanol/retinol interaction, and/or a mechanism involving pro-oxidant activity of retinol but anti-oxidant activity of beta-carotene. This article concludes with suggestions for further research to help clarify the association between retinol and human carcinogenesis.

Diet↗
PubMed1990

Alcohol and pregnancy. An epidemiologic perspective.

This article considers maternal use of alcohol during pregnancy, from an epidemiologic perspective. In general, maternal use of alcohol during pregnancy has been associated with a number of effects in offspring including fetal alcohol syndrome, a reduction in birth weight, effects on behavior, and other late effects. It is apparent from the existing literature that the epidemiologic dimensions of these effects are poorly defined and hampered by methodologic problems. Assessment of both outcome and exposure can be difficult, and there is great potential for uncontrolled confounding. Additionally, it is unclear whether the apparent teratogenicity of alcohol results from direct, acute effects of alcohol on the developing fetus, or results from chronic effects of excessive alcohol intake in the mother. This article concludes with recommendations for further research, which may help clarify the complexity of effects associated with maternal use of alcohol during pregnancy.

Abnormalities, Drug-Induced↗
PubMed1990

Familial clustering of neural tube defects and gastric cancer.

A retrospective cohort study was conducted to determine whether producing an offspring with a neural tube defect (NTD) is associated with the development of unusual patterns of cancer among the parents in subsequent years. Mothers and fathers who had a child with an NTD in Upstate New York from 1945 to 1955 were followed through 1979 and compared to a control group of parents with normal offspring. Overall mortality and site-specific cancer incidence were not significantly different for case parents versus control parents, with the exception of gastric cancer, which occurred significantly more frequently in case parents. The finding of a familial association between NTDs and gastric cancer, coupled with a parallel decline in rates of these two diseases, suggests a common aetiology, perhaps related to dietary factors.

Adult↗
PubMed1990

Beta-carotene and cancer prevention: what is the evidence?

A growing body of literature supports a possible role for beta-carotene in the prevention of human cancer. The most scientifically rigorous method for testing the hypothesis that beta-carotene has chemopreventive properties is with intervention trials, several of which are ongoing or soon to be initiated. Connecticut will be actively involved in three of these trials. This article reviews and critically evaluates the evidence supporting a role for beta-carotene in the prevention of human cancer, including animal studies, cell culture studies, epidemiologic studies, and intervention trials, and concludes with a brief description of chemoprevention research involving beta-carotene in Connecticut.

Animals↗
PubMed1989

Antioxidant activity of dietary canthaxanthin.

It has been suggested that canthaxanthin (CX), beta-carotene, and other carotenoids may inhibit carcinogenesis via antioxidant activity. CX has been shown to inhibit lipid peroxidation in liposomes; this experiment was designed to assess the antioxidant activity of CX in biological membranes. Chicks were fed semipurified diets supplemented with placebo beadlets or CX beadlets (5 g beadlets/kg diet; 0.5 g CX/kg diet) for five weeks. Diets were deficient in vitamin E and selenium to maximize the power of detecting an antioxidant effect of CX and to induce exudative diathesis, which is a vitamin E and selenium deficiency disease of chicks. Dietary CX had no effect on the onset, incidence, or severity of exudative diathesis. Liver homogenates from CX-fed chicks exhibited significantly (p = 0.02) decreased formation of thiobarbituric acid-reactive substances over time in ferrous ion-induced peroxidations. Because dietary CX increased hepatic alpha-tocopherol content, subsequent peroxidations were conducted in membrane fractions prepared from placebo and CX livers matched for alpha-tocopherol content. In this system, CX was marginally but inconsistently protective against peroxidation at both 15 torr O2 (p = 0.12) and 150 torr O2 (p = 0.07). Nanomolar changes in hepatic alpha-tocopherol, unlike CX, substantially altered rates of peroxidation. These results suggest that under these conditions, dietary CX increased resistance to lipid peroxidation primarily by enhancing membrane alpha-tocopherol levels and secondarily by providing weak direct antioxidant activity.

Animals↗
PubMed1986

Subcellular distribution of dietary beta-carotene in chick liver.

Studies were conducted examining the subcellular distribution of beta-carotene (BC), alpha-tocopherol (E) and retinol (A) in livers of control and BC-fed male White Leghorn chicks. Chicks were fed Cornell B chick starter diet with or without the addition of 0.5 g BC/kg diet. A first study involved liver fractionation by differential centrifugation in 0.25 M sucrose followed by high performance liquid chromatographic (HPLC) analyses of all fractions for quantitation of BC, E and A. A second study employed both intravenous injection of Triton WR-1339 four days prior to sacrifice and centrifugation in 1.0 M sucrose to separate mitochondria from lysosomes more efficiently. Fraction purity was assessed by marker enzyme analyses. Results showed that chick liver accumulated BC; BC-fed chicks had higher concentrations of BC in all fractions relative to controls, and the mitochondrial fraction contained the highest concentration of BC, followed by lysosomes, microsomes and nuclei, respectively. Plasma BC increased more than fivefold in BC-fed chicks. Dietary BC increased A and E levels in liver and in the mitochondrial and lysosomal fractions while the plasma E level was decreased. Plasma A changed little with BC feeding. While dietary BC had no effect on fatty acid composition of subcellular fractions, the increase in E resulted in a large increase in the molar ratio of E to polyunsaturated fatty acids. The incorporation of BC and increased amounts of E into cellular membranes presumably would result in increased resistance to peroxidative damage.

Acid Phosphatase↗
PubMedDate not supplied

Early detection of ovarian cancer: background, rationale, and structure of the Yale Early Detection Program.

Ovarian cancer has received national attention as a highly virulent disease. Its lack of early warning symptoms and the failure to develop highly sensitive screening tests have led some physicians to recommend prophylactic oophorectomies to women with relatives who have had ovarian cancer. Others have recommended routine screening of otherwise normal women for CA 125, a circulating tumor marker, and ultrasound examinations. Each of these techniques is associated with substantial false-positive rates that could lead to unnecessary surgery. A review of epidemiologic data suggests that familial ovarian cancer kindreds are rare, but women with first-degree relatives who have had ovarian cancer have a significant risk themselves for developing ovarian cancer. In addition, women with a great number of ovulatory cycles are at an increased risk for the disease. Circulating tumor markers are frequently elevated in women with advanced ovarian cancer, but their value in early detection of ovarian cancer has yet to be established. Advances in endovaginal ultrasound and color Doppler flow technology have significantly improved our ability to assess pelvic organs. This article presents the background, rationale, and structure of the Yale Early Detection Program for ovarian cancer, whose goals are to identify the best techniques for diagnosing ovarian cancer in an early stage, to determine the frequency with which such tests should be employed, to assess false-positive results, and to identify women who might benefit from prophylactic oophorectomies.

Biomarkers, Tumor↗
PubMedDate not supplied

Early detection of ovarian cancer: preliminary results of the Yale Early Detection Program.

Eighty-four women at high risk for ovarian cancer by having first-degree relatives with epithelial ovarian cancer participated in a newly established, early ovarian cancer detection program at Yale University. Participants were to be evaluated with physical examinations and circulating tumor markers at entry and every six months thereafter. Endovaginal ultrasound and color Doppler flow studies were to be performed at three and nine months following entry into the program. In addition, women were encouraged to follow American Cancer Society guidelines for mammography. Stool was checked for occult blood. Endometrial sampling was offered to post-menopausal women. No participant has developed an ovarian cancer since entering the program. One woman has been diagnosed to have breast cancer. False-positive levels of circulating tumor markers (CA 125, 4/84 [4.8 percent]; lipid-associated sialic acid in plasma, 13/84 [15.5 percent]; NB/70K, 4/84 [4.8 percent]; and urinary gonadotropin fragment, 1/65 [1.5 percent]) were observed on entry into the program. Low resistive indices (less than 0.5) were documented in 8/91 (8.8 percent) ovaries studied by the color Doppler flow technique. One participant underwent a laparotomy based on a false-positive endovaginal ultrasound examination. Tests now being employed in community practice have a high likelihood of being associated with false-positive results. Therapeutic interventions based on isolated abnormal tumor markers or ultrasound studies obtained from women with family histories of ovarian cancer may lead to inappropriate surgery. It is necessary for cancer centers to develop expertise in ovarian cancer detection techniques to advise physicians in their geographic areas appropriately about the significance of the abnormal screening test.

Adult↗