Lobular Invasive Carcinoma of the Male Breast: A Case Report of An Uncommon Disease

INTRODUCTION: The male breast cancer is rare, representing 1% of all breast cancers. The most common invasive subtype is infiltrating ductal carcinoma (85% of tumors). Invasive Lobular Carcinoma (ILC) is very unusual in men, representing 1% of male breast cancers. This probably occurs because lobules are not found in normal male breast tissue. The lobular development is associated to progesterone and estrogen action during menstrual cycles in the women breast. In a database with 843 patients diagnosed with ILC treated in INCA (Brazilian National Cancer Institute) between 2000 and 2009 we have found only one male patient. Here we report a case of ILC in a man that was previously treated with cyproterone. CASE REPORT: A 70 year old male patient was admitted to INCA in 2001 referring increased bilateral breast volume and ulceration of the left papilla. The patient had a prostate cancer story treated with surgery followed by radiotherapy and cyproterone acetate one year earlier. Physical examination revealed a 9.5 cm mass occupying the entire right breast and an ulcerated lesion measuring 12.5 cm in the left breast with bilateral linfonodal involvement (Stage IIIb). Mammography showed increased breast volume with bilateral densification, skin thickening and bilateral retraction of the nipple-areolar complex. Incisional biopsy showed poorly differentiated invasive carcinoma. Tamoxifen was prescribed for two months with no response. He started neoadjuvant chemotherapy (Adriamycin and Cyclophosphamide) but the disease remained stable after 3 cycles. It was performed bilateral Modified Radical Mastectomy on July 2000. Histopathological examination of surgical specimens revealed bilateral ILC, histologic grade II Elston. The left breast showed a 10.5 cm tumor and metastatic carcinoma to 4 lymph nodes from 15 isolated nodes. The right breast showed a 5.5 cm tumor and metastatic carcinoma to 2 lymph nodes from 10 isolated nodes. E-cadherin and hormone receptors were negative in both breasts. In March 2001, he presented cutaneous nodules in his left plastron. Lesion’s biopsy showed metastatic ILC. On May 2001 it was diagnosed bone metastasis. Palliative chemotherapy (5-Fluorouracil and Pamidronate) was started. He developed neutropenic fever and was hospitalized for treatment, but died from sepsis on August 2001. DISCUSSION: One of the most important risk factors to male breast cancer is an abnormal balance between estrogen and androgen. In this case, the patient used cyproterone, a steroid with progestin-like and antiandrogenic activity. This possibly could explain the development of lobules and consequently an increased risk of lobular carcinoma. Cyproterone is notoriously associated to gynecomastia, benign nodular breast hyperplasia and galactorrhea. Futhermore, there are reports of bladder and hepatic carcinoma related to it’s use. However there is still no well-established relationship between the use of cyproterone and breast cancer.