William P. McWhorter

Contribution of socioeconomic status to black/white differences in cancer incidence

Blacks and Whites have very different cancer incidence rates for many sites, but this may largely be due to the racial differences in socioeconomic status (SES). The authors tested this hypothesis by determining the effect of adjustment for SES on the black/white incidence ratios for 12 cancer sites. Race‐specific census tract‐level SES variables (median family income, percent below poverty level, and years of education) were obtained from the 1980 US census and applied to approximately 20,000 black and 88,000 white cancer cases from the National Cancer Institutes Surveillance, Epidemiology, and End Results (SEER) program for the years 1978 to 1982. For each cancer site (with each sex considered separately), Poisson regression was used to produce age‐adjusted black/white incidence ratios, with and without adjustment for SES. The SES variable with the strongest adjusting power was percent below poverty level. For many sites (breast, in situ and invasive cervix, esophagus, male lung, pancreas, stomach) poverty accounted for much or all of the racial differences. For several sites (bladder, multiple myeloma, prostate, uterine corpus), large racial differences persisted after adjustment for poverty, and these findings suggest directions for investigating the etiology of these cancers.

A screening study of prostate cancer in high risk families.

In a study of the familial risk of prostate cancer 17 sets of 2 brothers with prostate cancer were identified. A total of 34 first-degree relatives of these probands (sons and brothers, 55 to 80 years old) underwent an intensive screening examination that included prostate specific antigen, digital rectal examination, transrectal ultrasound and systematic as well as clinically directed core needle biopsies. Previously unsuspected and clinically relevant cancers were found in 8 men (24%), compared to the approximately 1 expected (p less than 0.01). Of these cancers 2 were detected by the systematic biopsies. This study emphasizes the importance of thorough screening in first-degree relatives of prostate cancer patients.

Colorectal cancers of rare histologic types compared with adenocarcinomas.

PURPOSE: To examine clinical characteristics of colorectal cancers of rare histologic types compared with adenocarcinomas. METHODS: Review of a population-based registry with complete ascertainment. RESULTS: There were 7,422 colorectal cancers, 4,900 (66 percent) colonic and 2,522 (34 percent) rectal. Two hundred fifty-five cancers (3 percent) were of nonadenocarcinoma varieties including 75 (33 percent) squamous, 74 (33 percent) malignant carcinoids, 37 (16 percent) transitional cell-like, 25 (11 percent) lymphomas, 9 (4 percent) sarcomas, and 2 (0.9 percent) melanomas. Sixty (1.2 percent) of the colon cancers occurred in the appendix, and proportionately more carcinoids accounted for these tumors. Compared with adeno-carcinomas, colonic and rectal carcinoids and colonic lymphomas accounted for a larger proportion of cancers in the younger age groups. The elderly had proportionately fewer colonic carcinoids. Colonic carcinoids, rectal squamous-cell cancers, and rectal transitional cell-like cancers were more common in women. Colonic lymphomas had a worse prognosis than adenocarcinomas. Survival was better with colonic and rectal carcinoids and rectal transitional cell-like cancers than with adenocarcinomas. CONCLUSIONS: Colorectal cancers of histologic varieties other than adenocarcinoma have distinctive epidemiologic and clinical traits.

Response:Proliferative Breast Disease: Diagnosis and Implication

M. H. Skolnick et at. (1) obtained specimens by multiple fine-needle aspiration from the breasts of women with and without a family history of breast cancer. They assessed the prevalence of certain cytologic changes in these groups of women, which they labeled proliferative breast disease (PBD). Skolnick et al.s use of this term is unfortunate because PBD is a well-recognized histologic diagnosis (2, 3) of changes that bear only a slight and untested resemblance to the cytologic findings in (1). In order to avoid confusion, we will hereafter use PBD in its conventional sense. Although PBD is consistently associated with increased breast cancer risk (4), studies have not been performed which show that cytologic abnormalities or similarly defined patterns have such an association. Skolnick