title: Synchronous colon primaries have the same prognosis as solitary colon cancers.
abstract: OBJECTIVE
  This study was designed to determine the prognosis of patients with synchronous colon primary tumors.
  
  
  METHODS
  An 18-year, multi-institutional database of 4,878 colon cancer patients was reviewed, and patients with synchronous tumors were identified. Survival for each group was calculated by the Kaplan-Meier method and compared using log-rank analysis.
  
  
  RESULTS
  There were 160 patients (3.3 percent) with 339 synchronous tumors. Eight percent of these patients had more than two tumors at the time of diagnosis. TNM staging of all synchronous tumors was 12 percent Stage 0, 41 percent Stage I, 21 percent Stage II, 16 percent Stage III, and 7 percent Stage IV. Based on highest stage lesion, 1 percent of patients were at Stage 0, 28 percent Stage I, 33 percent Stage II, 25 percent Stage III, and 11 percent Stage IV. Disease-specific five-year survival by highest stage was 87 percent for Stage 0 or I, 69 percent for Stage II, 50 percent for Stage III, and 14 percent for Stage IV (all differences significant by log-rank test). These "highest stage" survivals for patients with synchronous tumors were not significantly different from survival of patients with the same stage solitary tumors in our database or from survival of patients with solitary colon cancer in national tumor databases.
  
  
  CONCLUSIONS
  For patients with synchronous colon cancers, survival is the same as for patients with solitary colon tumors on a stage-for-stage basis, when highest stage synchronous tumor is considered.
authors.affiliation: Division of General Surgery, Section of Surgical Oncology, Oregon Health Sciences University, Portland, Oregon, 97201-3098, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Passman
authors.forename: R F
authors.initials: RF
authors.lastname: Pommier
authors.forename: J T
authors.initials: JT
authors.lastname: Vetto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003110:Colonic Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009378:Neoplasms, Multiple Primary / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D011379:Prognosis; D015996:Survival Rate; D016896:Treatment Outcome