An Unusual Case of Nodular Hidradenoma of Breast

Background: Nodular hidradenoma or clear cell hidradenoma is a rare adnexal tumor arising from the eccrine glands. Case Report: A 60-year old female presented to the surgical out-patient clinic with complaints of breast lump of one year duration. Fine needle aspirate (FNA) of the lump yielded fluidly aspirate mixed with hemorrhage. On Giemsa-stained smears, a possibility of benign cystic lesion was considered. A provisional diagnosis of nodular hidradenoma was made. Additional sections were taken to rule out another component which revealed no other cell type. Periodic Acid Schiff’s (PAS) stain showed diastase sensitive positivity in the cytoplasm of tumor cells. The tumor cells were negative for estrogen and progesterone receptor but were positive for smooth muscle antigen, confirming the final diagnosis of nodular hidradenoma. Conclusion: To conclude, awareness amongst both the clinicians and pathologists for the possibility of diagnosing NH is mandatory and it should always be kept as differential diagnoses in the tumors of nipple and subareolar region to avoid unwarranted mastectomy and lymph node dissection.