title: Comparison of long-term oncological outcomes of appendiceal cancer and colon cancer: A multicenter retrospective study.
abstract: BACKGROUND
  There has been no comparative study of the long-term oncological outcomes of appendiceal cancer and colon cancer. We hypothesized that the oncological outcome is worse in appendiceal cancer because perforation is more frequent than in colon cancer.
  
  
  METHODS
  Patients with stage I-III were selected from 5046 patients with appendiceal or colon cancer, between September 2001 and June 2010. The 5-year disease-free survival (DFS) was the primary endpoint. Multivariate analyses with Cox proportional hazards model for DFS and logistic regression model for perforation were conducted. A matching model was used to compensate for the heterogeneity between groups.
  
  
  RESULTS
  The perforation rate was 44.7% in appendiceal cancer (n = 47), but 1.1% in colon cancer (n = 2828) (p = 0.001). The 5-year DFS rate was lower in appendiceal cancer than in colon cancer (57.9% vs. 85.2%, p = 0.001; matching model, 54.2% vs. 78.4%, p = 0.038), with a higher rate of peritoneal seeding (25.5% vs. 2.5%, p = 0.001; matching model, 24.0% vs. 4.0%, p = 0.007). Multivariate Cox regression showed that appendiceal cancer was an independent prognostic factor for poor DFS (hazard ratio = 2.602, 95% confidence interval = 1.26-5.35, p = 0.009), and logistic regression confirmed that appendiceal cancer was the risk factor associated with perforation (odds ratio = 66.265, 95% confidence interval = 28.21-155.61, p = 0.001).
  
  
  CONCLUSIONS
  This study suggested that the long-term oncological outcomes are worse for appendiceal cancer than for colon cancer, attributed to higher perforation rate in appendiceal cancer.
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Il Tae
authors.initials: IT
authors.lastname: Son
authors.affiliation: Medical Research Collaborating Center, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Soyeon
authors.initials: S
authors.lastname: Ahn
authors.affiliation: Department of Surgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Kyu Joo
authors.initials: KJ
authors.lastname: Park
authors.affiliation: Center for Colorectal Cancer, National Cancer Center, Goyang, South Korea.
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Oh
authors.affiliation: Department of Surgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Seung-Yong
authors.initials: SY
authors.lastname: Jeong
authors.affiliation: Department of Surgery, Hallym University College of Medicine, Hallym University Hospital, Anyang, South Korea.
authors.forename: Hyoung-Chul
authors.initials: HC
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, South Korea.
authors.forename: Seung Chul
authors.initials: SC
authors.lastname: Heo
authors.affiliation: Department of Surgery, Daehang Hospital, Seoul, South Korea.
authors.forename: Eui Gon
authors.initials: EG
authors.lastname: Youk
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Jin-Taek
authors.initials: JT
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Myong Hoon
authors.initials: MH
authors.lastname: Ihn
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Heung-Kwon
authors.initials: HK
authors.lastname: Oh
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Duck-Woo
authors.initials: DW
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea. Electronic address: kangsb@snubh.org.
authors.forename: Sung-Bum
authors.initials: SB
authors.lastname: Kang
mesh_terms: D000230:Adenocarcinoma / Q000556:secondary* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001062:Appendectomy / Q000401:mortality*; D001063:Appendiceal Neoplasms / Q000473:pathology* / Q000601:surgery; D018279:Carcinoma, Signet Ring Cell / Q000556:secondary* / Q000601:surgery; D003082:Colectomy / Q000401:mortality*; D003110:Colonic Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007416:Intestinal Perforation; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010534:Peritoneal Neoplasms / Q000556:secondary* / Q000601:surgery; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D015996:Survival Rate; D055815:Young Adult
keywords: Appendiceal cancer; Colon cancer; Disease-free survival