title: Is primary tumor resection associated with a longer survival in colon cancer and unresectable synchronous metastases? A 4-year multicentre experience.
abstract: OBJECTIVE
  To explore the survival impact of primary tumor resection (PTR) in patients with metastatic colon cancer (mCC) and unresectable metastases.
  
  
  METHODS
  We retrospectively studied a multicenter cohort of consecutive mCC patients with unresectable metastases receiving first-line chemotherapy. A weighted Cox proportional regression model was used to balance for clinical variables associated with the probability of undergoing PTR, using inverse probability of treatment weighting (IPTW) based on a propensity score.
  
  
  RESULTS
  Ninety-six patients were included. PTR was performed in 69 (72%). The rates of secondary resection of metastases (p = 0.02) and bevacizumab administration (p = 0.02) were higher in the PTR group. Raw median overall survival (OS) was 23.1 months (95%CI[14.6-27.8]) in the PTR group and 22.1 months (95%CI[12.3-23.7]) in the non-PTR group (p = 0.11). After adjustment on IPTW, OS was 23.1 months (95%CI[17.0-28.7]) in the PTR group and 17.2 months (95%CI[13.5-22.2]) in the non-PTR group (HR 0.68; 95%CI[0.50-0.93]; p = 0.016). This result remained significant on multivariate analysis (HR 0.71; 95%CI[0.50-1.00]; p = 0.05).
  
  
  CONCLUSIONS
  In mCC patients with unresectable metastases receiving chemotherapy, up-front PTR was independently associated with prolonged OS. Patients eligible for secondary metastases resection and/or bevacizumab may benefit the most from PTR. Randomized controlled trials are mandatory.
authors.affiliation: Department of Hepato-Gastroenterology and Digestive Oncology, Robert-Debré University Hospital, Reims, France. Electronic address: louisdemestier@hotmail.com.
authors.forename: L
authors.initials: L
authors.lastname: de Mestier
authors.affiliation: Department of Gastroenterology and Pancreatology, Beaujon University Hospital, Clichy, France.
authors.forename: C
authors.initials: C
authors.lastname: Neuzillet
authors.affiliation: Unit of Methodology and Quality of Life in Oncology, EA 3181, Saint-Jacques University Hospital, Besançon, France.
authors.forename: A
authors.initials: A
authors.lastname: Pozet
authors.affiliation: Department of Hepato-Gastroenterology and Digestive Oncology, Robert-Debré University Hospital, Reims, France.
authors.forename: E
authors.initials: E
authors.lastname: Desot
authors.affiliation: Department of Digestive and Endocrine Surgery, Robert-Debré University Hospital, Reims, France.
authors.forename: S
authors.initials: S
authors.lastname: Deguelte-Lardière
authors.affiliation: Department of Hepato-Gastroenterology and Digestive Oncology, Robert-Debré University Hospital, Reims, France.
authors.forename: J
authors.initials: J
authors.lastname: Volet
authors.affiliation: Department of Digestive Surgery, Pitié-Salpetrière University Hospital, Assistance Publique Hôpitaux de Paris, Pierre et Marie Curie University, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Karoui
authors.affiliation: Department of Digestive and Endocrine Surgery, Robert-Debré University Hospital, Reims, France.
authors.forename: R
authors.initials: R
authors.lastname: Kianmanesh
authors.affiliation: Unit of Methodology and Quality of Life in Oncology, EA 3181, Saint-Jacques University Hospital, Besançon, France.
authors.forename: F
authors.initials: F
authors.lastname: Bonnetain
authors.affiliation: Department of Hepato-Gastroenterology and Digestive Oncology, Robert-Debré University Hospital, Reims, France. Electronic address: obouche@chu-reims.fr.
authors.forename: O
authors.initials: O
authors.lastname: Bouché
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000188:drug therapy; D057216:Propensity Score; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents
keywords: Colon cancer; Metastases; Palliative; Primary tumor; Prognosis; Resection