title: Relationships among primary tumor size, number of involved nodes, and survival for 8044 cases of Merkel cell carcinoma.
abstract: BACKGROUND
  The effects of primary tumor size on nodal involvement and of number of involved nodes on survival have not, to our knowledge, been examined in a national database of Merkel cell carcinoma (MCC).
  
  
  OBJECTIVE
  We sought to analyze a retrospective cohort of patients with MCC from the largest US national database to assess the relationships between these clinical parameters and survival.
  
  
  METHODS
  A total of 8044 MCC cases in the National Cancer Data Base were analyzed.
  
  
  RESULTS
  There was a 14% risk of regional nodal involvement for 0.5-cm tumors that increased to 25% for 1.7-cm (median-sized) tumors and to more than 36% for tumors 6 cm or larger. The number of involved nodes was strongly predictive of survival (0 nodes, 76% 5-year relative survival; 1 node, 50%; 2 nodes, 47%; 3-5 nodes, 42%; and ≥6 nodes, 24%; P < .0001 for trend). Younger and/or male patients were more likely to undergo pathological nodal evaluation.
  
  
  CONCLUSIONS
  The National Cancer Data Base does not capture disease-specific survival. Hence, relative survival was calculated by comparing overall survival with age- and sex-matched US population data.
  
  
  CONCLUSIONS
  Pathologic nodal evaluation should be considered even for patients with small primary MCC tumors. The number of involved nodes is strongly predictive of survival and may help improve prognostic accuracy and management.
authors: Department of Medicine/Dermatology, University of Washington, Seattle, Washington.
authors: Jayasri G
authors: JG
authors: Iyer
authors: Fred Hutchinson Cancer Research Center, Clinical Research Division, Seattle, Washington.
authors: Barry E
authors: BE
authors: Storer
authors: Department of Medicine/Dermatology, University of Washington, Seattle, Washington.
authors: Kelly G
authors: KG
authors: Paulson
authors: Department of Medicine/Dermatology, University of Washington, Seattle, Washington; Department of Dermatology, Emory University, Atlanta, Georgia.
authors: Bianca
authors: B
authors: Lemos
authors: Commission on Cancer of the American College of Surgeons, Chicago, Illinois.
authors: Jerri Linn
authors: JL
authors: Phillips
authors: Department of Dermatology, University of Michigan Health System, Ann Arbor.
authors: Christopher K
authors: CK
authors: Bichakjian
authors: Roswell Park Cancer Institute, Buffalo, New York.
authors: Nathalie
authors: N
authors: Zeitouni
authors: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Taxas.
authors: Jeffrey E
authors: JE
authors: Gershenwald
authors: H. Lee Moffitt Cancer Center and Research Institute and the University of South Florida, Tampa, Florida.
authors: Vernon
authors: V
authors: Sondak
authors: Department of Dermatology, Mayo Clinic, Rochester.
authors: Clark C
authors: CC
authors: Otley
authors: Department of Dermatology, University of California at San Francisco, San Francisco, California.
authors: Siegrid S
authors: SS
authors: Yu
authors: Department of Dermatology, University of Michigan Health System, Ann Arbor.
authors: Timothy M
authors: TM
authors: Johnson
authors: Department of Oncology and Plastic Surgery, Johns Hopkins, Baltimore, Maryland.
authors: Nanette J
authors: NJ
authors: Liegeois
authors: Department of Surgery, University of Washington, Seattle, Washington; Seattle Cancer Care Alliance, Seattle, Washington.
authors: David
authors: D
authors: Byrd
authors: Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts.
authors: Arthur
authors: A
authors: Sober
authors: Department of Medicine/Dermatology, University of Washington, Seattle, Washington; Fred Hutchinson Cancer Research Center, Clinical Research Division, Seattle, Washington; Seattle Cancer Care Alliance, Seattle, Washington. Electronic address: pnghiem@uw.edu.
authors: Paul
authors: P
authors: Nghiem
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015266:Carcinoma, Merkel Cell / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D015331:Cohort Studies; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000469:parasitology; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D016019:Survival Analysis; D047368:Tumor Burden; D014481:United States
keywords: Merkel cell carcinoma; National Cancer Data Base; average tumor size; neuroendocrine carcinoma of the skin; nodal spread; prognosis; regional node metastasis; sentinel lymph node biopsy