Squamoid Eccrine Ductal Carcinoma

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Squamoid eccrine ductal carcinoma (SEDC) is a rare primary cutaneous tumor.
• It presents a biphasic histologic appearance, often leading to misdiagnosis as squamous cell carcinoma (SCC) on initial biopsy due to superficial sampling.
• SEDC has a high risk of local recurrence and metastasis.

Purpose of the Study:

• To review the clinical and histologic details of patients with SEDC treated with Mohs micrographic surgery (MMS).
• To evaluate the efficacy of MMS in managing SEDC and distinguish it from SCC.
• To support MMS as the preferred treatment for SEDC.

Main Methods:

• Review of 5 patients with SEDC treated with MMS between November 2018 and May 2020.
• Analysis of clinical and histologic features, including immunohistochemical markers (CEA, EMA, CK 5/6, p63).
• Evaluation of treatment outcomes, recurrence rates, and metastasis after a mean follow-up of 11 months.

Main Results:

• All 5 patients with SEDC treated with MMS achieved complete tumor clearance.
• Multiple Mohs stages were required for complete tumor removal in all cases.
• No evidence of recurrence or metastasis was observed during the follow-up period.

Conclusions:

• Mohs micrographic surgery (MMS) is the treatment of choice for squamoid eccrine ductal carcinoma (SEDC).
• MMS allows for complete tumor clearance and minimizes the risk of recurrence and metastasis.
• Accurate histologic examination and immunohistochemistry are crucial for diagnosing SEDC and differentiating it from SCC.