Anaplastic large cell lymphoma of breast masquerading suppurative mastitis on cytology

Abstract

Breast is an uncommon site of extra nodal lymphoma accounting for 2.2% of all extra nodal lymphomas. B cell lymphomas are more common than T cell types. The most common subtype is Diffuse Large B Cell Lymphoma. Breast lymphoma is very challenging to diagnose as it has nonspecific clinical and radiological features. We report a rare case of primary T cell lymphoma in a 20-year-old female. It was misdiagnosed as abscess on ultrasound and as suppurative mastitis on fine needle aspiration cytology (FNAC). However, excisional biopsy was suggestive of lymphoma and immunohistochemistry confirmed it as ALK positive, anaplastic large cell lymphoma. Even though FNAC is a part of the diagnostic triad for breast lesions, potential pitfalls cannot be overlooked and must be correlated with biopsy.