title: Five hundred patients with Merkel cell carcinoma evaluated at a single institution.
abstract: OBJECTIVE
  To identify factors associated with survival in Merkel cell carcinoma (MCC).
  
  
  BACKGROUND
  Merkel cell carcinoma is a rare cutaneous neoplasm. Staging and treatment are based on studies, which incompletely characterize the disease.
  
  
  METHODS
  Review of a prospective database was performed. Overall survival (OS) was estimated by the Kaplan-Meier method. Disease-specific death (DSD) was analyzed by the competing risks method. Factors associated with OS and DSD were determined by the log-rank test and Gray's test, respectively.
  
  
  RESULTS
  A total of 500 patients with MCC treated at our institution from 1969 to 2010 were identified. Eighty-eight patients presented older than 6 months after diagnosis and were excluded from further analysis. Of the remaining 412 patients, the median age at diagnosis was 71 years. Median follow-up was 3 years. Fifty percent of patients died during follow-up: 25% died of disease, 24% died of other causes. Five-year OS and DSD were 56% and 30%, respectively. Pathologic stage and lymphovascular invasion were independent predictors of DSD. Patients with metastatic disease (stage 4) or clinically positive lymph nodes (stage 3b) had increased DSD compared with patients with microscopically positive (stage 3a) or negative lymph nodes (stage 1 and 2). There was no difference in DSD between stage 3a or 2 compared with stage 1. Importantly, only 1 of 132 patients without lymphovascular invasion died of MCC.
  
  
  CONCLUSIONS
  OS is a poor measure of the influence of MCC on life expectancy. The presence of lymphovascular invasion and clinically, but not microscopically, positive lymph nodes were associated with increased DSD. These factors should be incorporated into MCC staging and treatment recommendations.
authors.affiliation: Department of Surgery, Barnes-Jewish Hospital, Washington University School of Medicine, Louis, MO, USA.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Fields
authors.forename: Klaus J
authors.initials: KJ
authors.lastname: Busam
authors.forename: Joanne F
authors.initials: JF
authors.lastname: Chou
authors.forename: Katherine S
authors.initials: KS
authors.lastname: Panageas
authors.forename: Melissa P
authors.initials: MP
authors.lastname: Pulitzer
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Allen
authors.forename: Dennis H
authors.initials: DH
authors.lastname: Kraus
authors.forename: Mary S
authors.initials: MS
authors.lastname: Brady
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Coit
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D016190:Carboplatin / Q000008:administration & dosage; D015266:Carcinoma, Merkel Cell / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D002945:Cisplatin / Q000008:administration & dosage; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007260:Infusion Pumps; D000077146:Irinotecan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D012107:Research Design; D012878:Skin Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D005047:Etoposide; D000077146:Irinotecan; D016190:Carboplatin; D002945:Cisplatin; D002166:Camptothecin