Incidence of Kaposi's sarcoma in a cohort of homosexual men infected with the human immunodeficiency virus type 1. The Multicenter AIDS Cohort Study Group.

Longitudinal data on 2,125 participants in the Multicenter AIDS Cohort Study (MACS) with documented antibodies to the human immunodeficiency virus type 1 (HIV-1) were used to examine the incidence of acquired immune deficiency syndrome (AIDS)-related Kaposi's sarcoma (KS) over time and to determine if sexual practices and hematologic variables prior to diagnosis differed for participants who develop KS vs. non-KS AIDS (NKS). In the first 4 years of the study, 84 seropositive men were observed to develop KS and 307 presented with an AIDS diagnosis other than KS. A systematic trend in the incidence of KS over time was not apparent in this population. The number of anal-receptive intercourse partners prior to diagnosis declined in a similar fashion for both AIDS groups. Although the number of partners with whom the men performed rimming decreased prior to diagnosis for both AIDS groups, a greater proportion of the KS AIDS group had performed this activity with multiple partners than had the non-KS AIDS group. Furthermore, history of oral gonorrhea was significantly (p = 0.027) more prevalent in the KS group. In addition, the KS AIDS group had lower cytomegalovirus antibody levels prior to diagnosis and higher levels of total immunoglobulin G. The groups did not differ with respect to baseline hematological measures, temporal trends in helper and suppressor T cells, or hepatitis B surface antigen or antibody. Given this profile of factors associated with the occurrence of KS, an infectious agent, in addition to HIV-1, is plausible as a proposed cofactor in the development of KS.

Epidemiology and risk assessment for ovarian cancer.

The incidence of ovarian cancer varies internationally with higher rates among women of North America and northern Europe. In the United States, there has been relatively little change in the incidence of ovarian cancer in recent decades. The incidence rate of ovarian cancer is highest among white and Hawaiian women, intermediate among African-American, Hispanic and Asian-American women, and lowest among Native American women. The most intensively studied risk factors have been family history, pregnancy history, and oral contraceptive use. Multiparity, lactation, oral contraceptive use, and tubal ligation/hysterectomy all decrease a woman's risk of ovarian cancer. One exposure that has been consistently associated with increased ovarian cancer risk is cosmetic talc applied to the perineum.

Breast cancer and pesticides in Hawaii: the need for further study.

Only 30% of all breast cancer can be explained by known risk factors. Increases in breast cancer incidence rates in Hawaii over the past few decades cannot be attributed solely to improvements in screening and detection. Avoidable environmental factors may contribute to a proportion of the unexplained cases. Emerging evidence on endocrine disruption suggests that environmental chemicals may play a role in the development of breast cancer. Agricultural chemicals, including endocrine disruptors, have been used intensively in Hawaii's island ecosystem over the past 40 years leaching into groundwater, and leading to unusually widespread occupational and general population exposures. This paper discusses breast cancer patterns in Hawaii in the context of documented episodes of exposure to two endocrine-disrupting chemicals, chlordane/heptachlor and 1,2-dibromo-3-chloropropane (DBCP), at levels that sometimes exceeded federal standards by several orders of magnitude. In light of this history, detailed geographic-based studies should be undertaken in Hawaii to elucidate the potential role of environmental factors in the development of breast cancer and other diseases.

Biodosimetry of Chernobyl cleanup workers from Estonia and Latvia using the glycophorin A in vivo somatic cell mutation assay.

The reactor accident at Chernobyl in 1986 necessitated a massive environmental cleanup that involved over 600,000 workers from all 15 Republics of the former Soviet Union. To determine whether the whole-body radiation received by workers in the course of these decontamination activities resulted in a detectable biological response, over 1,500 blood samples were obtained from cleanup workers sent from two Baltic countries, Estonia and Latvia. Here we report the results of studies of biodosimetry using the glycophorin A (GPA) locus in vivo somatic cell mutation assay applied to 734 blood samples from these workers, to 51 control samples from unexposed Baltic populations and to 94 samples from historical U.S. controls. The data reveal inconsistent evidence that the protracted radiation exposures received by these workers resulted in a significant dose-associated increase in GPA locus mutations compared with the controls. Taken together, these data suggest that the average radiation exposure to these workers does not greatly exceed 10 cGy, the minimum levels at which radiation effects might be detectable by the assay. Although the protracted nature of the exposure may have reduced the efficiency of induction of GPA locus mutations, it is likely that the estimated physical doses for these cleanup worker populations (median reported dose 9.5 cGy) were too low to result in radiation damage to erythroid stem cells that can be detected reliably by this method.

Epidemiology of HIV associated non-Hodgkin lymphoma.

The excess of NHL associated with HIV infection is well established. Clinically, HIV associated NHL is characterized by histological evidence of a high grade of malignancy, B cell origin, extensive extranodal involvement (most notably of the CNS) and poor prognosis. High grade B cell lymphoma or primary brain lymphoma in HIV infected individuals is considered diagnostic of AIDS by the Centers for Disease Control. The incidence of NHL among individuals with AIDS varies by subtype of lymphoma, age, sex, race and risk group. Younger individuals, males, whites and haemophiliacs are at higher risk than other groups. The incidence of HIV associated NHL is increasing. Because of the paucity of data on risk factors for this malignancy, the current possibilities for risk modification are limited to the prevention of HIV infection.

Older women as the focus for research and treatment of ovarian cancer. An overview for the National Institute on Aging, National Cancer Institute, and American Cancer Society Multidisciplinary Working Conference.

Ovarian cancer disproportionately affects women 65 years of age and older who are likely to have concomitant changes in physical ability, physiological functioning, and other chronic conditions associated with advancing age. The National Institute on Aging, National Cancer Institute, and the American Cancer Society cosponsored a multidisciplinary working conference, "Perspectives on Ovarian Cancer in Older-Aged Women: Current Knowledge and Recommendations for Research," at the National Institutes of Health on November 20-21, 1991 to confront the age-related aspects of ovarian cancer in epidemiology, etiology, clinical investigations, and patient management. Conference participants devoted attention to such special topics as drug resistance, dose intensity, patterns of care, and screening potential for ovarian cancer. After exploring these areas with existing data, the task was then to generate recommendations for research and practice. The scope of the conference and an introduction to the proceedings are presented in this paper.