Is Porocarcinoma a Rare Entity as Previously Reported? A Case Series Presented in a Short Span with Repeating Misdiagnosis and Comparison to Existing Literature

Objective: Porocarcinomas are rare malignant eccrine sweat gland-derived tumors that are less than 0.005% of all malignant epithelial cutaneous tumors and are mostly seen in the lower extremities as reported in the literature. In this study, we aimed to present a case series of porocarcinoma that are initially referred to our center with various initial diagnoses and thereby raise the awareness of porocarcinoma when making a differential diagnosis of a skin tumor, both clinically and pathologically as it may drastically change the treatment modalities. Methods: Five cases of porocarcinoma with various initial pathologic diagnoses that were referred to our clinic between 2020 and 2022 were reviewed retrospectively. Collected data was compared to existing literature and changes to treatment modalities from the initial diagnosis were discussed. Results: There are a total of 5 porocarcinoma cases with different initial diagnoses. (4 cases male, 1 case female). The mean follow-up time of the cases is 25 months (13-36). In one case, locoregional lymph node metastasis was observed 4 months after tumor excision. In 5 cases, 2 are located in the trunk, 1 in the head and neck, 1 in the lower extremity, and 1 in the upper extremity. Complementary lymph node dissection was performed in only one patient. Conclusion: Eccrine porocarcinoma is presented as a very rare tumor, and both clinicians and pathologists should be more mindful of this tumor during differential diagnosis in order not to overlook this entity and miss additional treatment options needed to control porocarcinoma oncologically. Cite this article as: Yavuz E, Gökbaşı Ö, Önenerk Men AM, Aydın Ülgen Ö, Ercan A. Is porocarcinoma a rare entity as previously reported? A case series presented in a short span with repeating misdiagnosis and comparison to existing literature. Cerrahpaşa Med J. 2024;48(3):212-218.