A Rare Case of Remittent Male Invasive Ductal Carcinoma With New Metastasis After Incomplete Adjuvant Therapy.

Breast cancer is a rare disease in men with many barriers to effective management such as limited research and treatment modalities. While the current standard of care utilizes mastectomy and axillary dissection with chemotherapy, clinicians must follow the female-staged breast cancer protocol, as there is no established regimen for men. In this case presentation, we report a 43-year-old male with a prior history of ER-positive invasive ductal carcinoma (IDC) who presented with a recurrent breast lesion. The patient had previously undergone left breast mastectomy with sentinel node biopsy with negative margins. The patient declined adjuvant chemotherapy and tamoxifen therapy after the initial dissection. Three years after the primary dissection, the patient presents with a breast lesion and metastasis to bilateral axillary lymph nodes, lungs, and spine. The diagnosis was supported by a right axillary biopsy which revealed an ER-positive and PR-positive lesion. We want to shed light on the importance of complete and thorough treatment of primary IDC in men while highlighting the implications of incomplete treatment. We hope that this clinical case will serve as a guide for physicians in promoting adjuvant treatments after primary tumor removal in male IDC.