Second Primary Breast Cancer in Men with Prostate Adenocarcinoma Treated by Decapeptyl: A Case Report

Introduction: Breast cancer in men is a rare disease, especially in association with prostate cancer. Risk factors are multifactorial and include environmental factors, genetic susceptibility and hormonal treatments. Decapeptyl an analogue to gonadorelin (GnRH-agonist) used, in association with surgery, in treatment for prostate adenocarcinoma may likely cause breast cancer in these patients. Case presentation: A 56-year-old man followed for a non-metastatic prostate adenocarcinoma presents after ten months of treatment with Decapeptyl a breast tumor. After resection of the breast carcinoma, the histological find an invasive breast carcinoma no special type (NST) grade II of SBR. The immunohistochemical study of the tumor specimen was positive for estrogen receptor (70 to 100 % of tumoral surface), progesterone receptor (50 to 70 % of tumoral surface) and Hercep Test of score 3+ (HER 2 positive). Discussion: The risk of male breast cancer with long-term steroidal anti-androgens is well documented; however, the risk of male breast cancer with a synthetic gonadotropin-releasing hormone (GnRH) is extremely rare. Only one case presenting a breast cancer after treatment with leuprolide (GnRH-agonist) has been reported in the literature, and obviously this is the first case of mammary carcinoma in men secondary to treatment with Decapeptyl. The majority of these breast cancers in men are invasive breast carcinoma no-special type or unclassified. Other types of tumors are very rare. Decapeptyl contains the active ingredient Triptorelin used to treat prostate cancer, which normally has to decrease breast cancer risk, but in this case it appears to be involved in the appearance of breast carcinoma. Conclusion: This report illustrates a case of invasive breast carcinoma in a man followed for prostate adenocarcinoma and treated by Decapeptyl. This treatment seems to be the principal risk factor involved in the appearance of a second primary tumor in men diagnosed with prostate cancer.