Ectopic hidradenoma papilliferum of eyelid: A rare entity with diagnostic challenge.

Hidradenoma papilliferum is a rare cutaneous adnexal tumour of middle aged females arising mainly in the apocrine sweat glands of perianal and genital region. Ectopic forms of this entity have been described with majority of them occurring on the head and neck region. We report a case of 16 years young male who presented with two small, well circumscribed, greyish-brown, firm, nodules on his left upper and lower eyelid. A clinical impression of basal cell carcinoma was assumed but on histopathological examination it was diagnosed as hidradenoma papilliferum of eyelid. Immunohistochemistry was performed to support the diagnosis due to its unusual clinical presentation. To the best of our knowledge, only six cases in the upper eyelid and one case in the lower eyelid have been reported in the English literature. This is the first case report of hidradenoma papilliferum involving both upper and lower left eyelid in an adolescent boy.

Histomorphological and Immunohistochemical Reappraisal of Cutaneous Adnexal Tumours: A Hospital Based Study.

Background. Diagnosing adnexal tumours of the skin is a challenge due to their wide variety, infrequent occurrence in practice, and confusing morphological picture. Aims and Objectives. The present study aims to observe the spectrum of adnexal tumours at our institute and to evaluate them based on histomorphological, histochemical, and immunohistochemical methods either alone or in combination for proper identification and classification. Materials and Methods. A partly retrospective and partly prospective study was conducted on adnexal skin tumours over a period of 6 years. Relevant clinical profile was recorded. Histopathological examination was carried out and special stains were applied as and when required. Immunohistochemistry was performed where diagnosis with routine stains was not possible. Results. A total of 150 skin tumour biopsies were received. There were 87 keratotic tumours, 39 adnexal tumours, and 24 melanocytic tumours. Amongst the adnexal tumours, 51.3% eccrine, 30.8% follicular, and 17.9% sebaceous tumours were seen. In five cases, histological diagnosis was troublesome where immunohistochemistry helped in making final diagnosis. Limitations. The sample size is small. Conclusion. Histomorphology is confirmatory in majority of the adnexal tumours but few rare lesions that mimic internal malignancy require a panel of immunomarkers to rule out other possible differentials.