Clear Cell Hidradenoma of Breast Mimicking Atypical Breast Lesion: A Diagnostic Pitfall in Breast Cytology

Abstract

Clear cell hidradenoma (CCH) is an uncommon skin adnexal tumor arising from eccrine glands. Although several kind of skin adnexal tumors arise in the breast tissue, CCH of the breast is an extremely rare entity. Failure to identify its cytomorphologic features and rarity of this tumor may lead to misdiagnosis on fine needle aspiration cytology. Hereby we report a case of 30-year-old female who presented with painless lump in left breast since 10 months. Fine needle aspiration cytology of lump yielded fluid material. On May-Grunwald-Giemsa stained smears, a possibility of atypical breast lesion was considered and patient was advised a biopsy examination. Final diagnosis of CCH was made on histopathologic examination. Awareness of cytomorphologic features of breast CCH will prevent misdiagnosis as malignant or atypical breast lesions and will allow for correct management of the patients.

Eccrine hidradenoma of the breast: distinct pathological lesion mimicking a carcinoma

“…CCH shows reactivity for P63, keratin, EMA, CEA, S-100 and Vimetin but negativity for alpha-SMA, CD-10, ER, PR [4].…”

“…It occurs commonly in middle-aged and older adults, and can be found anywhere on the body without predilection for a particular site [1]. However common reported sites of origin of CCH are face, upper extremity, axilla, trunk, thigh, the ear Lobule, scalp and pubic region [4]. Although several skin adnexal tumors arise in the breast tissue, CCH of the breast is an extremely rare entity [3,4].…”

“…However common reported sites of origin of CCH are face, upper extremity, axilla, trunk, thigh, the ear Lobule, scalp and pubic region [4]. Although several skin adnexal tumors arise in the breast tissue, CCH of the breast is an extremely rare entity [3,4]. It usually manifests as an asymptomatic, solitary, firm, cutaneous nodule, measuring between 5 and 20 mm in diameter.…”

“…Rarely some lesions show squamous differentiation which is observed in our case. Furthermore, malignant transformation is possible but extremely rare [3] and has been observed in only few cases [4]. However, neither clinical behavior nor histological features can predict malignant change.…”

“…Usually, CCH is difficult to diagnose cytologically and in most studies, cytological diagno-sis was either unconclusive or misdiagnosed as breast tumor [4].…”