No abstract

Using an automated method for detecting mammographic mass, the authors evaluated the relation between quantitatively measured density and the risk of breast cancer in a case -control study among Japanese women. The case subjects were 146 women newly diagnosed and histologically confirmed with breast cancer at a general hospital. A total of 659 control women were selected from those who attended a breast cancer mass screening at this hospital. Significantly increased odds ratios (ORs) of breast cancer were observed for breast densities of 25 -49 and 50 -74%, but not for densities of 75 -100% as compared with 0% in premenopausal women after controlling for covariates (ORs ¼ 4.0, 4.3, and 1.4, respectively). In postmenopausal women, ORs were significantly increased for breast densities of 25 -50% (OR ¼ 3.0) and 50 -100% (OR ¼ 4.2). Total breast area was significantly associated with the risk of breast cancer independent of density percent or dense area in postmenopausal women. These data suggested that mammographic density was associated with the risk of breast cancer in Japanese women as is the case in Caucasian women. However, the associations of the risk of breast cancer with breast size and a high breast density greater than 75%, needs to be confirmed in future studies.

To investigate the relationship between the tumor growth rate of the primary breast cancer and its prognosis, records for 122 breast cancer patients in 9 hospitals in Japan were retrospectively reviewed. These records contained at least two measurements of the same tumor mass in the breast. So the growth rate was estimated from these measurements taken at different points in time. The doubling time of the breast tumors showed an approximately log‐normal distribution. The geometric mean of doubling times for all cases was 174 days. The solid‐tubular histologic type of carcinoma had the shortest geometric mean of doubling time (126 days), the scirrhous carcinoma had the second shortest one (205 days), and the papillotubular carcinoma had the longest one (252 days). The patients with shorter doubling time of tumor tended to have a poorer prognosis. The Cox multiple regression analysis showed that the tumor growth rate was related significantly with survival, after adjusting for other covariates such as clinical stage, lymph node metastasis, age of patient, histological type, and year of treatment.

Background: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. Methods: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. Results: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (z z z3.00 Mg/g creatinine) than in those with

Non-occupational exposure to cadmium has been suspected to be a risk factor for breast cancer. The present study examined the association between urinary cadmium level and the risk of breast cancer in a case-control study among Japanese women. Cases were 153 women newly diagnosed and histologically confirmed with breast cancer at a general hospital in Gifu, Japan. A total of 431 controls individually matched to cases by age, menopausal status, and the period of urine sampling were selected from those who attended a breast cancer mass screening at this hospital. Urinary cadmium levels were measured using spot urine samples. Spot urine samples were collected from cases after surgery but before any cancer therapy. For controls, spot urine samples were obtained at the date of the screening visit. Information on known or suggested breast cancer risk factors was obtained by a self-administered questionnaire. The odds ratios (ORs) and 95 % confidence intervals (CIs) of breast cancer according to the tertile of the creatinine-adjusted cadmium level were calculated using conditional logistic regression models. Women in the highest tertile of the creatinine-adjusted cadmium level (>2.620 μg/g) had significantly elevated OR of breast cancer relative to those in the lowest tertile (<1.674 μg/g) after controlling for covariates [OR = 6.05, (95 % CI 2.90, 12.62)]. The trend of increase in risk with increasing cadmium level was also statistically significant [OR = 1.67, (95 % CI 1.39, 2.01) for every 1.0 μg/g increase in urinary cadmium level, P-trend <0.01]. These data suggested that exposure to cadmium was associated with a risk of breast cancer in Japanese women.