Merkel cell carcinoma of the head and neck: potential histopathologic predictors.

Objective: To identify or confirm any new or suggested independent histopathological predictors in Merkel cell carcinoma (MCC) of the head and neck (HN) correlated with outcome.

Methods: Retrospective chart and pathology review. Methods: Between 1990 and 2010, 58 patients with Merkel cell carcinoma of the head and neck HNMCC were identified for study. Pathologic specimens were reviewed and evaluated for independent prognostic factors and correlated with locoregional recurrence and disease-specific survival.

Results: The 2- and 5-year disease-specific survival (DSS) rates were 72.7% and 63.6%, respectively. The local and regional recurrence rates were 12.0% and 24.1%, respectively. A total of 25.9% of the patients developed distant metastases during follow-up. Tumor size (< 1 cm vs. > 1 cm) and the presence of a positive deep resection margin were independently found to be significantly associated with regional recurrence (P = 0.01 and P = 0.04, respectively). No other prognostic factors could be identified.

Conclusions: Adjuvant radiotherapy cannot remediate a positive resection margin. Given these results, consideration for revision surgery should be considered for a positive deep margin. Frozen section analysis may help to define the margins in this invasive and aggressive disease.