Axillary Lymph Nodal Metastasis from Carcinoma of Unknown Primary (CUPAx)- An Orphan Disease

Metastasis to axillary lymph node occurs in adenocarcinoma or poorly differentiated carcinoma, and is a rare clinical entity that needs to be understood for management and its clinical outcome. The present case is of 72-year-old female patient who had a metastatic nodule in the axilla. No breast mass was palpable. Histology identified as metastatic adenocarcinoma, however mammography and Ultrasound Sonography test (USg) failed to detect the primary tumour. Immunohistochemistry showed that the excised lymph node was positive for Estrogen Receptor (ER) and negative for Progesterone Receptor (PR), suggesting the breast as the site for the primary tumour. Since the patient refused surgery, she was under follow-up for eight months. Now, she presented with recurrence of similar axillary swelling for two months.