Endocrine mucin-producing sweat gland carcinoma: a systematic review and meta-analysis.

Endocrine mucin-producing sweat gland carcinoma is a rare, under-reported cutaneous adnexal tumor that is often misdiagnosed and has an unknown incidence of metastasis. To determine the incidence of metastasis and tumor recurrence, as well as diagnostic accuracy and current trends in treatment modality. A search was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Tumor pathology and clinical data concerning demographics, presentation, diagnosis, treatment and follow-up were assessed. A total of 36 publications with 110 cases were identified. Initial pathological diagnosis was incorrect in 45.5% of cases. One case of metastatic disease was reported. The incidence of locoregional recurrence was 10.6% over a mean follow-up period of 21.3 months. Of cases with known methods of resection, 34.6% were resected by excisional biopsy, 42.8% were resected by wide surgical excision, and 31.3% were cleared by Mohs micrographic surgery. The low reported incidence and level of evidence was suboptimal with only case reports and retrospective case studies being reported. Reported cases of this pathology demonstrate poor diagnostic accuracy. High rates of misdiagnosis and inadequate definitive treatment suggest the need for more comprehensive work-up and management of lesions suspicious for this pathology.