AN UNUSUAL PRESENTATION OF METASTATIC THYMOMA IN THE AXILLARY TAIL OF THE BREAST: A DIAGNOSTIC CHALLENGE

Abstract

Thymomas are uncommon epithelial neoplasms arising from thymic tissue, typically located in the anterior mediastinum and predominantly affecting adults. Although these tumors are generally indolent, they may demonstrate invasive behavior and rarely metastasize beyond the thoracic cavity. Extrathoracic metastasis is distinctly unusual, and involvement of the breast or axillary tail is exceedingly rare. We report a case of a 45-year-old woman presenting with a painless axillary tail mass, which on evaluation was diagnosed as metastatic thymoma. This case highlights the diagnostic challenges posed by unusual metastatic sites and underscores the critical role of histopathology and immunohistochemistry in establishing the diagnosis. Awareness of such atypical presentations is essential to avoid misdiagnosis and ensure appropriate management.