For lymph node-positive Merkel cell carcinoma (MCC), lymph node ratio (LNR) offers a potentially prognostic metric alongside traditional TNM Classification of Malignant Tumors staging that may be useful for both patient counseling and treatment planning after surgery, according to a recent study. Researchers conducted a retrospective cohort study of patients with node-positive MCC treated with surgery and lymphadenectomy. They queried the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results (SEER) registry for patient records. They found:

• 736 eligible cases in the NCDB and 538 eligible cases in the SEER registry were identified.
• Among these 1,274 patients, the mean (SD) age was 71.1 (11.5) years, and 401 (31.5%) were women.
• After controlling for clinical and tumor factors, patient LNR of 0.07 to 0.31 (hazard ratio [HR], 1.37) and >0.31 (HR, 2.84) was associated with significantly worse survival than an LNR <0.07.
• For patients with an LNR >0.31, treatment with surgery and adjuvant chemoradiation therapy was associated with improved survival compared with surgery and adjuvant radiation therapy alone (HR, 0.61), while this was not found for patients with an LNR of ≤0.31 (HR, 0.93).