Clinicopathological features, <scp>MCPyV</scp> status and outcomes of Merkel cell carcinoma in <scp>solid‐organ</scp> transplant recipients: a retrospective, multicentre cohort study
Carla Ferrándiz‐Pulido, Álvaro Gómez‐Tomás, B. Llombart, D. López Mendoza, Joaquim Marcoval, Stefano Piaserico, Can Baykal, Jan Nico Bouwes-Bavinck, Emöke Rácz, Jean Kanitakis, Catherine Harwood, Petra Cetkovská, Alexandra Geusau, V. del Mármol, Emili Masferrer, Carmen Orte Cano, J. Ricar, Walmar Roncalli de Oliveira, Rafael Salido‐Vallejo, E. Ducroux, M.A. Gkini, José Antonio López‐Guerrero, Heinz Kutzner, Werner Kempf, Deniz Seçkin
Abstract
BACKGROUND: The proportion of Merkel cell carcinomas (MCCs) in solid-organ transplant recipients (SOTR) harbouring Merkel cell polyomavirus (MCPyV) is unknown, as are factors affecting their outcomes. OBJECTIVE: To describe clinicopathological features of MCC in SOTR, investigate the tumoral MCPyV-status and identify factors associated with tumour outcomes. METHODS: Retrospective, international, cohort-study. MCPyV-status was investigated by immunohistochemistry and polymerase chain reaction. RESULTS: A total of 30 SOTR and 44 consecutive immunocompetent patients with MCC were enrolled. SOTR were younger at diagnosis (69 vs. 78 years, P < 0.001). Thirty-three percent of SOTR MCCs were MCPyV-positive vs. 91% of immunocompetent MCCs (P = 0.001). Solid-organ transplantation was associated with an increased cumulative incidence of progression (SHR: 3.35 [1.57-7.14], P = 0.002), MCC-specific mortality (SHR: 2.55 [1.07-6.06], P = 0.034) and overall mortality (HR: 3.26 [1.54-6.9], P = 0.002). MCPyV-positivity and switching to an mTOR inhibitor (mTORi) after MCC diagnosis were associated with an increased incidence of progression (SHR: 4.3 [1.5-13], P = 0.008 and SHR: 3.6 [1.1-12], P = 0.032 respectively) in SOTR. LIMITATIONS: Retrospective design and heterogeneity of SOTR cohort. CONCLUSIONS: MCPyV appears to play a less prominent role in the aetiopathogenesis of MCC in SOTR. SOTR have a worse prognosis than their immunocompetent counterparts and switching to an mTORi after the diagnosis of MCC does not improve progression.