Diagnosis and treatment of clear cell hidradenocarcinoma of the scalp.

Clear cell hidradenocarcinoma (CCH) is an exceedingly rare and highly malignant tumor of the eccrine sweat glands. Its treatment is extremely difficult due to the characteristically aggressive clinical course including repeated local recurrence and uncontrollable distal metastasis coming along with a very poor prognosis. Most published case studies recommend a wide surgical excision followed by adjuvant conservative therapy, which is generally considered to be the standard treatment. Two cases of nodular CCH of the scalp either presenting as a singular primary lesion or at an already metastatic stage were analyzed retrospectively. Wide local excision of the tumor couldn't prevent the primary carcinoma from recurring and metastasizing. Both cases received various therapies but the results were unsatisfactory. Although most authors have recommended that early wide surgical excision of the tumor is a feasible therapeutic measurement, our results raise doubts on the efficacy of this treatment strategy. As alternative approaches (i.e. chemotherapy, radiotherapy) are similarly controversial, further studies and a wide exchange of clinical experiences are crucial.