Chiken Shibuya

Mammographic density and the risk of breast cancer in Japanese women

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=4.0, 4.3, and 1.4, respectively). In postmenopausal women, ORs were significantly increased for breast densities of 25–50% (OR=3.0) and 50–100% (OR=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.

Urinary cadmium and serum levels of estrogens and androgens in postmenopausal Japanese women.

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 (≥3.00 μg/g creatinine) than in those with low urinary cadmium (<2.00 μg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. Conclusion: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies.

Associations of Mammographic Density with Dietary Factors in Japanese Women

Background: A high percentage of mammographic dense area has been strongly associated with a risk of beast cancer. The present cross-sectional study evaluated the relations of percent density with dietary factors, such as fats, protein, dietary fiber, and soy isoflavones. Methods: Study subjects were 601 (348 premenopausal and 253 postmenopausal) Japanese women who were recruited from a mammographic screening center. The size of the total breast area and the dense area were measured quantitatively using an automated mammographic mass detection method. Intakes of nutrients were estimated with a validated semiquantitative food-frequency questionnaire. Results: The crude means of the percent density were 39.2% and 18.9% in premenopausal and postmenopausal women, respectively. There were no significant associations of any dietary factors with the percent density in premenopausal women. In postmenopausal women, percent density was significantly positively associated with intakes of protein, total fat, and saturated fat after controlling for covariates; the increase in the means of percent density were 7.2%, 5.6%, and 9.2% in the highest versus lowest quartile of intakes for protein, total fat, and saturated fat, respectively (P for linear trend were 0.006, 0.04, and 0.01, respectively). Carbohydrate intake was inversely associated with percent density; the mean of percent density was 6.0% lower in the highest versus the lowest quartile of intake (Ptrend = 0.03). The associations of dietary factors with dense area were very similar to those with percent density. Conclusion: These dietary factors may have implications for the risk of breast cancer in postmenopausal women. (Cancer Epidemiol Biomarkers Prev 2005;14(12):2877–80)

Light Exposure at Night, Urinary 6-Sulfatoxymelatonin, and Serum Estrogens and Androgens in Postmenopausal Japanese Women

It has been hypothesized that exposure to light at night increases the risk of breast cancer by suppressing the normal nocturnal increase in melatonin production and release, thereby resulting in increased levels of circulating estrogen. We assessed associations among concentrations of serum estrogen and androgen and the principal metabolite of melatonin in urine, 6-sulfatoxymelatonin, and exposure to light at night based on information regarding the sleeping habits and history of graveyard-shift work of 206 postmenopausal Japanese women. Serum estradiol level was significantly higher in women who were not asleep at or after 1:00 a.m. (the approximate time of the melatonin peak) than those who were asleep after controlling for covariates. Significantly increased estrone levels were observed in women who had worked graveyard shift. Serum testosterone and DHEA sulfate were unrelated to sleeping habits and history of graveyard-shift work. Urinary 6-sulfatoxymelatonin was lower in women who were not asleep at or after 1:00 a.m. on weekends than those who were asleep at this time, but the difference was of borderline significance (P = 0.08). There was no significant association between urinary 6-sulfatoxymelatonin and any serum hormone levels. These data suggest that exposure to light at night has implications for the risk of breast cancer in postmenopausal women. However, the potential role of melatonin as an intervening factor between light exposure at night and the serum concentrations of estrogen was equivocal. (Cancer Epidemiol Biomarkers Prev 2008;17(6):1418–23)

Induction of a cerebellar disorder with cycasin in newborn mice and hamsters.

Summary A single administration of cycasin, β-d-glucosyloxyazoxymethane, was given in dosage near the LD50 level to newborn mice and hamsters within 24 hr after birth. Under these conditions cycasin produced a distinctive neurologic disorder. In the affected newborns there was rapid and extensive necrosis of the cells of the external granular layer (embryonal layer) of the cerebellum. In animals surviving to maturity this resulted in defective development of the molecular and granule cell layers. The affected animals had ataxia and gait disturbances. Comparable administration of cycasin to rats within 24 hr after birth produced no apparent disorder of the central nervous system.

Association of Vegetable Intake with Urinary 6-Sulfatoxymelatonin Level

Melatonin is present in plants consumed as vegetables; however, only a limited number of vegetables have been tested for melatonin. The antiproliferative, antioxidative, and immunostimulatory effects of melatonin have been reported from laboratory studies. The potential protective effects of vegetable against cancer and cardiovascular disease may be partially attributable to an increased melatonin intake from vegetables. As a first step to test this hypothesis, we evaluated whether vegetable intake is associated with an increased urinary melatonin in 289 community-dwelling Japanese women. Diet, including vegetable consumption, was assessed with a validated 169-item semiquantitative food-frequency questionnaire. Urinary 6-sulfatoxymelatonin (aMT6-s) was measured in the first-void morning urines. There was a significant positive association between vegetable intake and urinary aMT6-s levels. The mean urinary aMT6-s was 16% higher in women with the highest quartile of vegetable intake than it was in those with the lowest quartile of intake. This association may be explained by the melatonin contained in vegetables. However, data should be regarded as preliminary because it is impossible to estimate dietary melatonin intake from vegetables and or from the entire diet because of incomplete data for melatonin in plants.

Dietary and lifestyle correlates of urinary excretion status of equol in Japanese women.

The isoflavone metabolite equol has been identified in urine or blood samples in some but not all humans. In this cross-sectional study, we examined the association between lifestyle, including diet, and the urinary excretion of equol. Study subjects were 419 Japanese women who were recruited from a breast cancer screening center. Each woman responded to a self-administered questionnaire seeking information about health and lifestyle factors. Diet was assessed by a validated semiquantitative food frequency questionnaire. Urinary isoflavones were measured using spot urine samples. Equol was detected in the urine of 84 (20.0%) women. After controlling for covariates, it was found that dairy product intake was significantly lower in those who excreted detectable equol levels in urine than in those who did not. Because equol is derived from daidzein, individuals with low intake of daidzein may produce undetectable levels of equol. To account for this, the study subjects were restricted to 163 women with urinary daidzein levels of 10 nmol/mg creatinine or higher. The association of equol excretion with dairy product intake remained significant. Demographic factors, smoking status, and menstrual and reproductive factors were unrelated to equol excretion. These data suggest that dairy product intake may be associated with the production of equol.

AN AUTOPSY CASE OF CRONKHITE-CANADA'S SYNDROME -GENERALIZED GASTROINTESTINAL POLYPOSIS, PIGMENTATION, ALOPECIA and ONYCHOTROPHIA –

A case of Cronkhite‐Canadas syndrome characterized by diffuse gastrointestinal polyposis, alopecia, nail atrophy, and pigmentation of the skin is reported. These ectodermal changes are probably a part of a generalized nutritional deficiency state and their clinical prominence may be related to the extensive involvement of all segments of the digestive tract. The macroscopic findings of the gastrointestinal tract were different at various sites, but the microscopic picture was uniform and characterized by proliferation of mucus secreting glands and cyst‐like dilations of the gland excepting the cancerous lesions of the sigmoid and rectum. The etiology of the syndrome remains obscure.

Carcinoid tumor in the female urethral orifice: Rare case report and a review of the literature

We experienced an extremely rare tumor in the female urethral orifice in a 57‐year‐old Japanese woman. To our knowledge, only two cases of primary urethral carcinoid tumor have been reported. The previous reports of urethral carcinoid tumor were recognized in the male middle urethra and penile urethra. The present case was resected, and diagnosed as a carcinoid tumor by histological, immunohistochemical and ultrastructural findings. The tumor cells were stained by chromogranin A, synaptophsin and neuron‐specific enolase, and neurosecretory granules were confirmed with electron microscopy. The patient did not complain of any symptoms until 5 years after the resection of the tumor. Therefore, the case we describe here is the first known report of carcinoid tumor in the Japanese female urethra.

The numerical aberrations of chromosome 7 detected by fluorescence in situ hybridization in human breast cancers

The relationship between the numerical aberrations of chromosome 7 in interphase cells and the clinicopathological behavior of breast tumors was investigated in 51 touch imprinted preparations of breast tumors. Using fluorescence in situ hybridization with a chromosome 7‐specific DNA probe, the fluoresceinisothiocyanate (FITC) spots mean and the representative copy number of each breast tumor were examined. The FITC spots mean (2.34) of 40 breast cancers increased compared with that of 11 benign lesions (1.98) (P < 0.02). The FITC spots mean tended to increase with the advancing stage and tumor size of the breast cancer. The FITC spots mean in the case with metastasis was also of a higher value than that without metastasis (P < 0.01). Furthermore, the existence of trisomy or over‐trisomy of the copy number was related to the advancing stage and tumor size (P < 0.05 and P < 0.01, respectively). These findings suggest that the FITC spots mean and polysomy of the number of chromosome 7 may be highly predictive for breast tumor aggressiveness.