De-Escalating Surgery in Merkel Cell Carcinoma With Clinical Nodal Disease.

Background: Merkel cell carcinoma (MCC) is a radiosensitive aggressive skin cancer that spreads via the lymphatics. There is uncertainty regarding the optimal management of the nodal basin for patients with MCC with clinically positive nodes. We study the efficacy of single node excision (SNE) as an alternative to a therapeutic lymph node dissection (TLND) in patients with limited nodal disease.

Methods: We performed a retrospective cohort study of patients with MCC with clinical nodal disease who underwent resection in the form of either SNE or TLND using the National Cancer Database. The association between type of surgery and overall survival (OS) was estimated using the Kaplan-Meier method and Cox proportional hazards modeling.

Results: 1835 patients met all inclusion criteria with 281 patients undergoing SNE and the remainder undergoing TLND. Patients receiving SNE and TLND were equally likely to receive radiation to the nodal basin (SNE 44.5% vs. TLND 48.5%, p = 0.22). There was no difference in 5-year OS between patients who received SNE versus TLND (SNE 43.9% vs. TLND 44.7%, p = 0.36). This persisted in a multivariable Cox proportional hazards model in which receipt of SNE remained not significantly associated with survival after adjusting for clinical and treatment factors including receipt of radiation (Hazard Ratio [HR] 1.17, 95% CI 0.96-1.42, p = 0.11). In patients undergoing SNE with radiation, 5-year OS was 54.4% (95% CI 44.1-63.6).

Conclusions: TLND is not associated with a survival advantage over SNE. Further prospective study into patterns of recurrence and safety of SNE is needed.