title: CD8+ lymphocyte intratumoral infiltration as a stage-independent predictor of Merkel cell carcinoma survival: a population-based study.
abstract: OBJECTIVE
  Intratumoral CD8+ lymphocytes (IT-CD8s) have shown promise as a prognostic indicator for Merkel cell carcinoma (MCC). We tested whether IT-CD8s predict survival among a population-based MCC cohort.
  
  
  METHODS
  One hundred thirty-seven MCC cases that had not previously been analyzed for IT-CD8s were studied.
  
  
  RESULTS
  Three-year MCC-specific survival rates were 56%, 72%, and 100% for patients with absent (n = 46), low (n = 85), and moderate or strong (n = 6) IT-CD8s, respectively. Increased IT-CD8s were associated with improved MCC-specific survival in a multivariate competing risk-regression analysis including stage, age, and sex (hazard ratio [HR] = 0.5; 95% confidence interval [CI] = 0.3-0.9). Although a similar trend was observed for overall survival, statistical significance was not reached (HR = 0.8; 95% CI = 0.6-1.0), likely because of the high rate of non-MCC deaths among older patients.
  
  
  CONCLUSIONS
  This study of prospectively captured MCC cases supports the concept that cellular immunity is important in MCC outcome and that CD8+ lymphocyte infiltration adds prognostic information to conventional staging.
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Kelly G
authors.initials: KG
authors.lastname: Paulson
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Jayasri G
authors.initials: JG
authors.lastname: Iyer
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: William T
authors.initials: WT
authors.lastname: Simonson
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Astrid
authors.initials: A
authors.lastname: Blom
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Renee M
authors.initials: RM
authors.lastname: Thibodeau
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Miranda
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle;
authors.forename: Stephanie
authors.initials: S
authors.lastname: Pietromonaco
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland; and.
authors.forename: Monica
authors.initials: M
authors.lastname: Sokil
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland; and.
authors.forename: E Margaret
authors.initials: EM
authors.lastname: Warton
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland; and.
authors.forename: Maryam M
authors.initials: MM
authors.lastname: Asgari
authors.affiliation: From the Departments of Medicine/Dermatology and Pathology at the University of Washington, Seattle; Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle WA. pnghiem@uw.edu.
authors.forename: Paul
authors.initials: P
authors.lastname: Nghiem
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D015266:Carcinoma, Merkel Cell / Q000276:immunology* / Q000401:mortality / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012878:Skin Neoplasms / Q000276:immunology / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate
keywords: Merkel cell carcinoma; Survival; T cells