Malignant adnexal tumors of the skin: a single institution experience

BACKGROUND: Malignant adnexal tumors of the skin (MATS) are rare. We aimed to measure the survival of patients with MATS and identify predictors of improved survival. METHODS: A retrospective review of MATS treated at our institution from 1990 to 2012. RESULTS: There were 50 patients within the time period. Median age was 59.5 years (range 22–95); primary site was the head and neck (52%); most common histologic subtypes were skin appendage carcinoma (20%) and eccrine adenocarcinoma (20%); and the vast majority were T1 (44%). Most patients (98%) underwent surgical treatment. Chemotherapy and radiation were administered to 8 and 14% of patients, respectively. Recurrence rate was 12%. Median OS was 158 months (95% CI, 52–255). OS and recurrence-free survival at 5 years were 62.4 and 47.4% and at 10 years 56.7 and 41.5%, respectively. Five-year and 10-year disease-specific survival (DSS) was 62.9%. Age > 60 years was an unfavorable predictor of OS (HR 12.9, P < .0008) and recurrence-free survival (RFS) (HR 12.53, P < .0003). Nodal metastasis was a negative predictor of RFS (HR 2.37, P < 0.04) and DSS (HR 7.2, P < 0.03) while treatment with chemotherapy was predictive of poor DSS (HR 14.21, P < 0.03). CONCLUSIONS: Younger patients had better OS and RFS. Absence of nodal metastasis translated to better RFS and DSS. Lymph node basin staging is worth considering in the workup and treatment.