Malignant eccrine poroma

Abstract

Benign eccrine poroma arises from the intraepidermal portion of the eccrine gland duct. Malignant transformation is rare and should be suspected when these lesions present with pain, bleeding or itching. We report a 44-year-old male patient who presented primarily with a lesion diagnostic of benign eccrine poroma of the right foot sole with no clear evidence of malignancy, which was incompletely excised, followed 5 months later by local recurrence, ulceration, occasional bleeding and right inguinal lymphadenopathy. Incomplete excision of the primary tumor as well as excision of a skin lesion on the right knee joint revealed malignant eccrine poroma with aggressive histology, lymphovascular and perineural invasion. Investigations revealed no evidence of distant metastasis. This tumor might be malignant at the first presentation, which was not confirmed histopathologically considering the short duration of only 5 months for malignant transformation. The patient received 3 cycles of Docetaxel Taxotere, Cisplatin combination chemotherapy with partial response. The management of metastatic malignant eccrine poroma is difficult. It has proven resistant to many chemotherapeutic agents and radiotherapy.