During aging female rats enter an anovulatory condition with chronically elevated circulating levels of estrogen described as persistent estrus (PE). Since this endocrine state is dramatically different from the fluctuating steroid milieu of young regularly cycling females, interpretations of altered neuroendocrine responses in aged rats have been difficult to attribute to aging per se. In the present study, young cyclic and middle-aged PE rats were treated with an LHRH agonist, [DTrp6, Pro9-NHEt]-LHRH, continuously (2.5 µg/h) for 12 days to suppress gonadotropin and ovarian steroid secretion. On the evening of the first day of LHRH agonist (LHRH-AG) treatment both young cyclic and middle-aged PE rats showed marked (p < 0.01) increases in plasma LH and FSH followed by progressive decreases in gonadotropin secretion which reached significantly (p < 0.05) lower levels than pretreatment values by day 7. LHRH-AG treatment significantly (p < 0.01) reduced circulating 17β-estradiol (E2) levels in both young and PE rats while progesterone concentrations did not change. Following LHRH-AG treatment, ovariectomy (OVX) resulted in increases of plasma LH and FSH that were delayed and attenuated in PE rats as compared to those of young females. When compared to non-treated rats, 12 days of LHRH-AG treatment in both young and PE females had a minimal and transient effect on the post-OVX gonadotropin responses, suggesting that the endocrine status immediately prior to OVX does not profoundly influence the post-OVX responses in young cyclic and middle-aged PE rats. Furthermore, LHRH-AG treatment does not appear to have permanent inhibitory effects on the hypothalamic-pituitary axis. Following LHRH-AG treatment in intact rats, the rebound in FSH secretion was delayed and prolonged in PE females and these rats did not return to estrous cyclicity. The results of these studies indicate that the neuroendocrine responses to the removal and return of ovarian negative feedback are impaired in PE rats, and suggest that these rats have a permanent dysfunction in the hypothalamic-pituitary-ovarian axis.
Background. Evidence on the management and treatment of male breast cancer is scant. We report the analysis of a multicenter Italian series of patients with male breast cancer treated with eribulin. To our knowledge, this is the first report on the use or eribulin in this setting. Patients and Methods. Patients were retrospectively identified in 19 reference centers. All patients received eribulin treatment, according to the standard practice of each center. Data on the identified patients were collected using a standardized form and were then centrally reviewed by two experienced oncologists. Results. A total of 23 patients (median age, 64 years; range, 42-80) were considered. The median age at the time of diagnosis of breast cancer was 57 years (range, 42-74). HER2 status was negative in 14 patients (61%), and 2 patients (9%) had triple-negative disease. The most common metastatic
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