Sentinel node status and immunosuppression: recurrence factors in localized Merkel cell carcinoma

The prognostic value of the sentinel lymph node in Merkel cell carcinoma (MCC) has been examined previously in heterogeneous retrospective studies. The current retrospective study included a homogeneous population of patients with a localized MCC, all staged with sentinel lymph node biopsy. Factors associated with 3-year progression-free survival were analysed using logistic regression. The sentinel lymph node was positive in 32% of patients. The recurrence rate was 26.9%. In first analyses (n = 108), gender (p = 0.0115) and the presence of immunosuppression (p = 0.0494) were the only significant independent factors. In further analyses (n = 80), excluding patients treated with regional radiotherapy, sentinel lymph node status was the only significant prognostic factor (p = 0.0281). Immunosuppression and positive sentinel lymph node are associated with a worse prognosis in patients with MCC. Nodal irradiation impacts on the prognostic value of the sentinel lymph node status.