Unmasking the Uncommon: A Case Report on a Rare Malignant Adnexal Tumour

Introduction: Malignant nodular hidradenoma, also called as hidradenocarcinoma is a rare neoplasm arising from the eccrine glands. The tumour has a slow onset with varied disease course and is generally associated with recurrence and metastasis. It usually affects head, trunk and extremities region and commonly seen in the fifth decade. Patient presents as a solitary nodule. These lesions can arise denovo as well as from a benign nodular hidradenoma. Case summary: We present a case of a 49 years old lady who presented with a nodule on the right side of the upper abdomen since 10 years. The swelling was gradually increasing in size and was associated with watery discharge since 3 years and intermittent pain. Examination showed it to be a 3x4cm mass in the right hypochondrium, it was mildly tender and overlying skin was normal. Wide local excision was done with rhomboid flap. Histopathological examination along with Immunohistochemical studies concluded a diagnosis of Malignant hidradenocarcinoma. Conclusion: Literature shows few cases of Malignant hidradenocarcinoma, since the incidence is low. As it is associated with poor prognosis, hence an accurate diagnosis is very essential for treatment of the patient. Keywords: hidradenocarcinoma, adnexal tumour, eccrine tumour