title: Tumor location is an independent prognostic factor in head and neck Merkel cell carcinoma.
abstract: OBJECTIVE
  Explore the relationship between tumor location and prognosis among patients with Merkel cell carcinoma (MCC) of the head and neck.
  
  
  METHODS
  Retrospective analysis of large population database.
  
  
  METHODS
  Surveillance Epidemiology and End Results (SEER) database/multiple settings.
  
  
  METHODS
  Using the SEER database, the authors identified patients with MCC of the head and neck. They compared clinicopathologic characteristics and disease-specific survival (DSS) between patients with head and neck MCC at different anatomic subsites. DSS was estimated by the Kaplan-Meier method, and a multivariable regression model was constructed so that independent predictors of DSS could be determined.
  
  
  RESULTS
  Of the 2104 patients identified, 61.0% were men. The mean age at diagnosis was 77.5 years. Tumors were most commonly located on the face (61.1%). Scalp tumors were significantly larger (10.4% >5 cm, P = .0001) and more likely to present with distant metastasis (8.7%, P = .07) than other head and neck tumors. Lip tumors had the highest rate of invasion into bone, cartilage, and muscle (13.7%, P = .012), and ear tumors had the highest rate of nodal metastasis (63.2%, P = .011). Patients with scalp/neck and lip primary sites had significantly worse survival on univariable analysis (P = .0054 and P = .0007, respectively); however, the lip was the only site associated with worse survival on multivariable analysis (hazard ratio = 1.8, P = .005).
  
  
  CONCLUSIONS
  This study is the first to report lip location as an independent prognostic factor in head and neck MCC. More aggressive treatment of patients with MCC of the lip may be warranted to improve outcomes.
authors.affiliation: College of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425-5500, USA.
authors.forename: Valerie A
authors.initials: VA
authors.lastname: Smith
authors.forename: Olivia P
authors.initials: OP
authors.lastname: MaDan
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Lentsch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015266:Carcinoma, Merkel Cell / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006258:Head and Neck Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D018426:SEER Program; D012878:Skin Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D016019:Survival Analysis; D016896:Treatment Outcome