Takao Shigematsu

Relationship between estrogen receptors and risk factors of breast cancer in Japanese pre- and postmenopausal patients

SummaryThe relation between estrogen receptors (ER) in breast cancer and risk factors was studied in 456 Japanese patients. ER was shown to be positive in 55.3% (252/456) of patients. There was no difference in ER positivity between pre- and postmenopausal patients. In premenopausal patients, only the age at menarche and obesity showed some influence on the ER positivity of breast cancer. Among postmenopausal patients, on the contrary, ER(+) cancers were predominant in the patient groups that have been known to be higher in the risk of incidence of breast cancer. The factors included were the age at marriage, number of pregnancies, number of live children, and body weight. Of these, the body weight of patients was the strongest influence on the ER positivity in the postmenopausal patients. After excluding the effects of body weight, some of the reproductive factors such as number of pregnancies and number of live children were shown to be related to the ER status. These results may suggest the combination of lower incidence of breast cancer and lower percentage of ER(+) cancers in Japanese postmenopausal women as compared with the Western countries.

Anthropometric Indicators of Breast Cancer Risk in Japanese Women in Fukuoka

This study was based on a case‐control study of breast cancer risk in Fukuoka, which was initiated to identify risk factors for the disease. We re‐analyzed the data of the study to evaluate the association of breast cancer with anthropometric variables in postmenopausal women. Data were obtained through interviewing 121 cases with historically confirmed breast cancer and an equal number of age‐matched hospital controls as well as neighborhood controls. The variables used for analysis were; height, weight at various ages, shoe size, and brassiere size and body size indices (body surface area and various body build indices) computed from the height and weight data. In a multiple covariance analysis, the results showed that cases were slightly lighter in weight and smaller for some of the indices, but the differences were not statistically significant. The odds ratios, estimated by multiple logistic regression analysis, suggested that the cases were slightly shorter in height and smaller in shoe size without any consistent dose‐response gradients. The effect of changes in weight and body size indices with aging were also assessed, but no significant findings were observed. The results reported here do not support the hypothesis of the positive association between obesity or large body size and breast cancer.

Histopathological Features and Their Association with Steroid Receptors in Women With Breast Cancer in Fukuoka, Japan

In Fukuoka, Japan, infiltrating duct carcinoma predominated among 213 breast cancer cases, age 45 to 74. Lobular and medullary carcinomas were infrequent. About thirty three percent of the women had marked productive fibrosis, based on the UICC code type. Both rough margin and productive fibrosis of the cancer increased with age of the patients. On the contrary, most of accompanying hyperplastic lesions decreased with age. The difference was significant for cystic formation between 10‐year age groups of 45–54 and 55–64 (b.χ2 = 6.61, p<0.02).

Cancer and other causes of death among Koreans in Fukuoka, Japan, 1976-1986.

Mortalities from cancer and other causes among Koreans living in Fukuoka, Japan, between 1976 and 1986 were examined as compared with those of Japanese in the prefecture. Korean males had a marked excess in all‐cause mortality, while the excess among females was less prominent. In both sexes, mortalities from liver cancer, liver cirrhosis, accident and suicide were markedly increased in the Korean population. These findings are in agreement with those observed among Koreans in Osaka. Although 20–30% lower‐than‐Japanese mortality from stomach cancer has been reported for Koreans in Osaka, those in Fukuoka had a risk of this cancer comparable to that of Japanese. A life‐style survey of Koreans in Japan might provide a better understanding of the disease patterns observed in this population.