Interrelation between Western type cancers and non-Western type cancers as regards their risk variation in time and space. IV. Hormonal transition of Japanese women from the pro-cervical cancer age through the pro-endometrial cancer age to the pro-hypogonadism age.

Chronological trend of urinary steroid excretions in Japanese women was investigated during the period of June 1972 to August 1986 using healthy women of urban and rural origins, patients with breast cancer and patients with either cervical cancer or endometrial cancer. The excretions of 14 neutral steroids were estimated by gas liquid chromatography, and the obtained data were tentatively correlated with the epidemiological backgrounds. In the course of the chronological transition from the 1st stage (1972-1974) to the 2nd stage (1975-79), the urinary steroid pattern of Japanese women with and without cancer experienced a common change to produce specific deviations that were in agreement with the hormonal characteristics of a pill user or of an endometrial cancer patient. At the 3rd stage (1980-86), patients with either cervical cancer or endometrial cancer were distinguished from 1st stage controls by non-specific depression of all androgens, progestins and corticosteroids in urine. Throughout the whole period, both the risk for cervical cancer and the reproductive activity (birth rate) were found to decrease continuously in Japanese women. Evidence was presented to suggest that the above deterioration of the hormonal environment in Japanese women could be related to the stress of modern life rather than to defects in the diet. On the basis of the above findings, the 1st, 2nd and 3rd stages of our investigation were tentatively termed the pro-cervical cancer age, the pro-endometrial cancer age and the pro-hypogonadism age. The relation between the chronological change of urinary steroids and that of the epidemiological background was analyzed from the view point of population ecology.