Environmental factors and breast and prostatic cancer.

Despite epidemiological evidence supporting a causal relationship between environmental factors and the development of breast and prostatic cancers, direct confirmation is unproven. Differences in hormone profiles in cancer patients and in patients with an increasing number of potential risk factors together with differences n life style and diet, suggest a relationship between diet, hormonal metabolism, and these endocrine-associated cancers. Modification of hormonal status by diet in men and women at different risk suggests that specific dietary components play a major role in these diseases.

Diet, lifestyle, and menstrual activity.

Menstrual activity is dependent on a critical body weight and may, therefore, be modified by nutritional factors. Lower plasma levels of testosterone, androstenedione, dehydroepiandrosterone, and prolactin, and differences in gonadotrophin levels were found during the menstrual cycle in rural black South African versus white women. When premenopausal vegetarian South African black women were fed a Western diet, plasma testosterone and prolactin levels increased, while estradiol decreased and follicle-stimulative hormone increased. In postmenopausal black women a similar diet decreased plasma leutinizing and follicle-stimulating hormone and increased prolactin levels. Differences between white and black women eating their customary diets may be related to genetic factors and/or lifestyle and diet. However, a Western diet induced changes in hormonal activity in vegetarian black women. These changes in hormonal levels in black women were comparable to those found in women with menstrual irregularities. Further study is needed to determine whether the difference in hormonal activity during the menstrual cycle between vegetarian black and white women may in part explain the lower incidence of coronary heart disease and breast cancer in the former.

Prolactin levels in populations at risk for breast cancer.

The basal plasma concentration of prolactin was determined by radioimmunoassay in Caucasian women at different risk for breast cancer and in three cases of women at risk for breast cancer. Samples taken under comparable conditions showed similar basal levels at birth and in prepubertal Bantu and Caucasian girls, or in healthy pre- and postmenopausal Bantu, Caucasian, or Japanese women. Elevated plasma prolactin levels were found in women castrated prior to 35 years of age and in women whose first pregnancy occured after 35 years. Evidence indicates that the prolactin/estrogen relationship may not be similar in women 35 to 45 years of age as compared to young women and suggests that elevation of serum prolactin per se does not appear to be related to an increased risk of breast cancer. The prolactin level was increased only in Caucasian women with breast cancer. If a high prolactin/estradiol ratio increases the susceptibility of the mammary epithelium to neoplastic growth, the lack of changes in prolactin levels in premenopausal Japanese patients and in postmenopausal patients of the three ethnic groups indicates that other factors are involved. Further study of the effects of life-style and diet on the basal level and stimulated release of prolactin is required to resolve the relationship of prolactin to breast cancer.

Plasma hormone levels in different ethnic populations of women.

It has been suggested that the urinary hormone profile is subject to environmental changes, such as urbanization and Westernization, and that the composition of the hormones can be used as a discriminate in determining the patient at risk for breast cancer. In this study, a comparison of the plasma hormone levels in Bantu and Japanese women, low-risk populations, and Caucasian women, a high-risk population, showed a higher level of 17 beta-estradiol in prepubertal girls and young Bantu and Japanese women. The higher estrogen level in the Bantu was evident in the early luteal and late follicular phases of the menstrual cycle. The difference in the dehydroepiandrosterone and testosterone levels in Bantu young women and prepubertal Bantu girls, suggests differences in adrenal activity between Bantu and Caucasian women. A fall in the plasma androstenedione was evident in postmenopausal Bantu and Japanese but not Caucasian women. Data suggest that the hormone profile is different among the 3 ethnic groups in both the pre- and postmenopausal women. Since the daily life-style of the women is comparable, it is suggested that the composition of the hormone profile is partially dependent on dietary on dietary factors.

Plasma hormone profiles in populations at different risk for breast cancer.

Evidence suggests that the reliability of urinary androgens or estrogens as prognostic discriminants for breast cancer may vary with different populations and may bear little relation to changes in plasma hormone levels. In this study the plasma estradiol level was significantly lower in Bantu, but did not in Caucasian, women with breast cancer, while the proportion of plasma androstenedione to dehydroepiandrosterone increased in Bantu patients. These changes in the plasma hormone profile in Bantu patients, a low-risk population for breast cancer, imply a change in ovarian and/or adrenal activity. Lack of similar hormone changes in Caucasian patients may be due to the initial differences in the hormone profile between the healthy Caucasian and Bantu women and to the different environmental factors that promote the breast disease in Western women.

Hormonal therapy of breast cancer with special reference to Masteril therapy.

From 1968 to 1972, a trial of a new agent, drostanolone propionate (Masteril), was conducted. This agent was tested against oophorectomy in a group of premenopausal patients, against nandrolone phenylpropionate (Durabolin) in a perimenopausal group, and against ethinyl oestradiol in a postmenopausal group. In the premenopausal group, 44% responded to Masteril and 22% to oophorectomy. In the perimenopausal group, 34,5% responded to Masteril and 39% to Durabolin. In the postmenopausal group, 57% responded to oestrogens and 38,5% to Masteril. The side-effects of Masteril are generally not serious and rarely contra-indicate its use. Masteril has been shown to be a useful and safe agent for all age groups, even though it may appear to be less effective than oestrogens in the postmenopausal patients.