title: Merkel Cell Carcinoma Analysis of Outcomes: A 30-Year Experience.
abstract: BACKGROUND
  Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy with poor prognosis. Limited data exists to guide treatment decisions. Here we report on our institutional experience and outcomes treating patients with MCC.
  
  
  METHODS
  A database search (1984-2014) of patients treated at the University of Wisconsin Hospital and Clinics was used to identify patients with histologically confirmed MCC. Patient, tumor, and treatment characteristics were examined via review of medical records. Statistical analyses were performed to assess outcomes and associated prognostic factors.
  
  
  RESULTS
  A total of 87 patients with MCC were identified with a median follow-up of 17 months (mean: 38, range: 0-210 months). Two and five-year overall survival rates were 53.9% and 32.8%, respectively. Recurrence was documented in 31.0% of patients (85.2% locoregional, 48.1% distant and 33.3% both). Patients with a history of immunosuppression exhibited significantly worse survival (hazard ratio, 2.01; 95% CI, 1.1-3.7) when compared to immune-competent individuals. The head and neck region was the most common location of primary lesion (N=49) followed by the extremities (N=31). Upper extremity primaries predicted significantly better overall survival (hazard ratio, 0.48; 95% CI, 0.23-0.99) while lower extremity primaries did not have significantly better results (hazard ratio, 0.5; 95% CI, 0.21-1.2) in comparison to head and neck site of primary. Nodal involvement (hazard ratio, 2.95; 95% CI, 1.5-5.79) was also a negative prognostic factor associated with poor overall survival when compared with clinically node negative patients. Primary tumor size > 2 cm (hazard ratio, 1.76; 95% CI, 0.91-3.4) was not associated with survival.
  
  
  CONCLUSIONS
  This study highlights the role of various factors in determining prognosis of Merkel cell carcinoma; history of immunosuppression, nodal involvement, and head/neck primary predicted worse overall survival. These findings suggest that improvements in both distant and locoregionally directed therapies might play an important role in control of MCC and identify areas for future study.
authors.affiliation: Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Evan
authors.initials: E
authors.lastname: Liang
authors.affiliation: Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Jeffrey V
authors.initials: JV
authors.lastname: Brower
authors.affiliation: Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Stephanie R
authors.initials: SR
authors.lastname: Rice
authors.affiliation: Department of Pathology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Darya G
authors.initials: DG
authors.lastname: Buehler
authors.affiliation: Department of Biostatistics, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Saha
authors.affiliation: Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America; University of Wisconsin Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States of America.
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Kimple
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000473:pathology / Q000628:therapy*; D003710:Demography; D023381:Endpoint Determination; D005260:Female; D006801:Humans; D007165:Immunosuppression Therapy; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000473:pathology / Q000628:therapy*; D016896:Treatment Outcome