Joseph Chu

Progestagen supplementation of exogenous oestrogens and risk of endometrial cancer

The favourable effects of exogenous progestagen on the endometrium are well known, but have not been adequately quantified with respect to endometrial cancer. The benefits of progestagen need to be weighted against its possible untoward effects on the risk of breast cancer and cardiovascular disease. A population-based case-control study of endometrial cancer was undertaken to evaluate the benefits of progestagen use. 158 incident cases were identified between 1985 and 1987 among women aged 40-64 years who were residents of King County, Washington. Detailed interviews were conducted and the responses were compared with those of 182 controls selected by random telephone digit dialling. The risk of endometrial cancer among women who had used unopposed oestrogen for more than 3 years was over five times that of women who had used no hormones (relative risk [RR] 5.7, 95% confidence interval [Cl] 2.5-12.8), whereas those who had also used a progestagen for at least six months of that time had an RR of only 1.6 (95% Cl 0.6-3.9). The RR differed according to days per month that progestagen was used: 2.4 (0.6-9.3) for progestagen use of less than 10 days per month versus 1.1 (0.4-3.6) for use of 10 or more days per month. These results provide additional evidence that the use of progestagen for 10 or more days per cycle can reduce the excess risk of endometrial cancer associated with long-term postmenopausal oestrogen use.

Treatment modality and quality differences for black and white breast cancer patients treated in community hospitals

This study assessed the relationship of race and patterns of care, defined by an expert NCI-appointed committee, for 7,781 patients with breast cancer treated in 107 hospitals in 45 communities between 1982 and 1985. After control for age and stage of disease, black patients had significantly different care from white patients for four of the ten patterns examined. They were less likely to have a progesterone receptor assay or to be referred for postmastectomy rehabilitation, two patterns deemed desirable for all patients. Black patients were also more likely to receive liver scans and radiation therapy in situations in which these procedures were labeled “less appropriate (as defined in the text).” Black patients differed significantly from whites on their health insurance, hospital, and physician characteristics; these factors were also significantly associated with the patterns of care. However, after controlling for these variables, the association between race and care persisted for three patterns. The patterns that showed racial differences were not the most clinically significant of the ten studied. Different treatment for black and white patients may help to explain differences in survival rates of black and white women with breast cancer.

Compliance Behavior in Women With Abnormal Pap Smears: Developing and Testing a Decision Model

This study investigated the reasons why women choose whether or not to seek treatment after being notified about an abnormal Pap smear in a womens clinic in Seattle. A hierarchic weighted utility model was developed from in-depth open-ended interviews with women who had an abnormal Pap smear and was used to identify beliefs and values related to the decision to seek treatment, i.e., a repeat Pap smear, for an abnormal Pap smear. Interviews with 18 women who had an abnormal Pap smear produced 12 issues pertinent to the behavior in question. These issues were grouped to form the hierarchy, and the decision model was then administered to 44 additional women. The model accurately classified the compliance behavior of 68% of study subjects. Moreover, the model differentiated persons who sought treatment for an abnormal Pap smear along several important dimensions: 1) doctors opinion; 2) the accuracy or seriousness of the Pap smear result; 3) the importance of early detection; 4) familiarity with the treatment procedure; 5) time hassles (i.e., difficulties) involved in getting further treatment; 6) femininity concerns; 7) fear of cancer; and 8) perceived risk of cancer. These dimensions suggest specific content areas that may be used to develop low-cost compliance intervention strategies for use in clinical settings.

Survival among women with endometrial cancer: a comparison of estrogen users and nonusers.

In order to determine the role of postmenopausal estrogen use in survival of patients with endometrial cancer, we identified, through a population-based tumor registry serving the area, all white women in King County, Washington, aged 50 to 74, who developed endometrial cancer between January, 1975, and April, 1976 (N = 363). Estrogen use prior to diagnosis and survival status were ascertained through personal interview, medical records of private physicians, and registry follow-up data. The 4-year relative survival ratio in estrogen users was 1.05 compared to 0.898 in nonusers. Overall, after adjustment for age, the survival in estrogen users was significantly better than in nonusers (chi 2 = 30.5; p much less than 0.0001). While estrogen use may predispose to an increased incidence of endometrial cancer, it appears that such use does not lead to increased mortality from this condition.

Medical student exposure to blood and infectious body fluids.

Few data assess the exposure of students to blood or other potentially infectious body fluids during medical school. Fourth-year medical students completed a written survey immediately before graduation describing exposures during their last 2 years. Nearly one half of all graduating students recalled at least one exposure, with only 40% of these exposures reported to supervising house staff or faculty. Clerkships with the highest exposure rates were emergency medicine, surgery, and obstetrics-gynecology.

Studying patterns of cancer care: how useful is the medical record?

Records of hospital inpatients were abstracted for 5,000 newly diagnosed cancer patients admitted in 1982-83 to 17 Comprehensive Cancer Centers and 17 Community Hospital Oncology Programs. Generally available data items (silent record rate less than 5 per cent for the typical institution) included: age, race, sex, dates of hospitalization, zip code of residence, pathological stage, dates of biopsy and surgery, numbers of nodes examined and positive, certain diagnostic procedures, and some radiotherapy descriptors. For other data items, there was enormous variability in completeness and high institution-to-institution variation. Record completeness did not differ consistently between comprehensive and community cancer centers. We conclude that the hospital patient record is useful for tracking the frequency of surgical and related events. However, studies of diagnostic and therapeutic procedures should not rely solely on the hospital medical record due to the high rates of silent records.

Active learning in epidemiology and biostatistics

A study was undertaken to assess whether students who were exposed to case‐based active learning for epidemiology and biostatistics had a knowledge base similar to that of those who had undergone traditional lecture‐based teaching. Identical multiple‐choice questions were given to both groups as part of the final examination. Eighty‐five percent of the active‐learning group answered the questions on study design correctly as compared with 78% of the lecture group. Similarly, 76% of the active‐learning group answered the biostatistics questions correctly compared with 73% of the lecture group. The conclusion is that study design and biostatistics can be taught to students through case‐based active learning with similar if not higher knowledge levels, as assessed through objective multiple‐choice examination.