title: Primary Tumor Resection and Overall Survival in Patients With Metastatic Colorectal Cancer Treated With Palliative Intent.
abstract: The survival impact of primary tumor resection in patients with metastatic colorectal cancer (mCRC) treated with palliative intent remains uncertain. In the absence of randomized data, the objectives of the present study were to examine the effect of primary tumor resection (PTR) and major prognostic variables on overall survival (OS) of patients with de novo mCRC.
  
  
  
  Consecutive patients from the Australian 'Treatment of Recurrent and Advanced Colorectal Cancer' registry were examined from June 2009 to March 2015. Univariate and multivariate Cox proportional hazards regression analyses were used to identify associations between multiple patient or clinical variables and OS. Patients with metachronous mCRC were excluded from the analyses.
  
  
  
  A total of 690 patients de novo and 373 metachronous mCRC patients treated with palliative intent were identified. The median follow-up period was 30 months. The median age of de novo patients was 66 years; 57% were male; 77% had an Eastern Cooperative Oncology Group performance status of 0 to 1; and 76% had a colon primary. A total of 216 de novo mCRC patients treated with palliative intent underwent PTR at diagnosis and were more likely to have a colon primary (odds ratio [OR], 15.4), a lower carcinoembryonic antigen level (OR, 2.08), and peritoneal involvement (OR, 2.58; P < .001). On multivariate analysis, PTR at diagnosis in de novo patients was not associated with significantly improved OS (hazard ratio [HR], 0.82; 99% confidence interval [CI], 0.62-1.09; P = .068). PTR at diagnosis did not correlate with outcome in de novo patients with a colon primary (HR, 0.74; 99% CI, 0.54-1.01; P = .014) or a rectal primary (HR, 0.81; 99% CI, 0.27-2.44; P = .621).
  
  
  
  For de novo mCRC patients treated with palliative intent, PTR at diagnosis does not significantly improve OS when adjusting for known major prognostic factors. The outcomes of randomized trials examining the survival impact of PTR are awaited.
authors.affiliation: Andrew Love Cancer Centre, University Hospital Geelong, Geelong, VIC, Australia; Deakin University School of Medicine, Waurn Ponds, VIC, Australia. Electronic address: shufen.wong81@gmail.com.
authors.forename: Shu Fen
authors.initials: SF
authors.lastname: Wong
authors.affiliation: Department of Medical Oncology, Royal Melbourne Hospital, Parkville, VIC, Australia; Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia.
authors.forename: Hui Li
authors.initials: HL
authors.lastname: Wong
authors.affiliation: Department of Medical Oncology, Royal Melbourne Hospital, Parkville, VIC, Australia.
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Field
authors.affiliation: Department of Medical Oncology, Royal Melbourne Hospital, Parkville, VIC, Australia; Department of Medical Oncology, Western Health, Footscray, VIC, Australia.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Kosmider
authors.affiliation: Department of Medical Oncology, Royal Melbourne Hospital, Parkville, VIC, Australia; Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia; Department of Medical Oncology, Western Health, Footscray, VIC, Australia.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Tie
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; Department of Medical Oncology, Eastern Health, Box Hill, VIC, Australia; Monash University Faculty of Medicine, Nursing and Health Sciences, Clayton, VIC, Australia.
authors.forename: Rachel
authors.initials: R
authors.lastname: Wong
authors.affiliation: Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Melbourne EpiCentre, Parkville, VIC, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Tacey
authors.affiliation: Cabrini Health, Malvern, VIC, Australia.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Shapiro
authors.affiliation: Department of Medical Oncology, Royal Hobart Hospital, Hobart, TAS, Australia.
authors.forename: Louise
authors.initials: L
authors.lastname: Nott
authors.affiliation: Cabrini Health, Malvern, VIC, Australia.
authors.forename: Gary
authors.initials: G
authors.lastname: Richardson
authors.affiliation: Department of Medical Oncology, Eastern Health, Box Hill, VIC, Australia.
authors.forename: Prasad
authors.initials: P
authors.lastname: Cooray
authors.affiliation: Department of Surgery, Colorectal Surgery Unit, University of Melbourne, Royal Melbourne Hospital, Parkville, VIC, Australia.
authors.forename: Ian
authors.initials: I
authors.lastname: Jones
authors.affiliation: Department of Surgery, Western Hospital, Footscray, VIC, Australia.
authors.forename: Matthew
authors.initials: M
authors.lastname: Croxford
authors.affiliation: Department of Medical Oncology, Royal Melbourne Hospital, Parkville, VIC, Australia; Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia; University of Melbourne, Parkville, VIC, Australia; Department of Medical Oncology, Western Health, Footscray, VIC, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Gibbs
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000401:mortality* / Q000601:surgery*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010166:Palliative Care; D016016:Proportional Hazards Models; D012042:Registries; D055815:Young Adult
keywords: Bowel cancer; Incurable; Prognosis; Surgery; Synchronous neoplasms