Sentinel Node Biopsy In The Initial Evaluation Of 87 Patients With Merkel Cell Carcinoma.

9015 Background: Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine tumor. The objective was to determine the role of sentinel lymph node biopsy (SNB) in the management of patients with MCC. Methods: A SNB procedure was proposed to all patients, from 5 hospitals, referred for a MCC without palpable regional lymph node from 1999 to 2013. Features between positive (SNB+) and negative (SNB-) SNB patients (pts) were compared using a Fisher’s exact test. Results: Eighty-seven pts with a F/M ratio=0.85, a median age =74 yrs (31-90 yrs; 63% aged at least 70 yrs), a stage T1 (N=54), T2 (N=30) or T3 (N=3), a location on extremities (56%), head and neck (32%) or trunk (12%) were included. Among pts, 8% were immunosuppressed. The frequency of SNB metastasis (20/83=24% of successful SNB) did not differ significantly in T1 and T2 stages (p= 0.4). 19/20 SNB+ pts had a radical lymph node dissection and additional positive lymph nodes were found in 6/19 (31%) pts. Adjuvant radiotherapy was delivered to the pr...