title: Sidedness is prognostic in locoregional colon cancer: an analysis of 9509 Australian patients.
abstract: Right sided colon cancer (RsCC) is proposed to be a distinct disease entity to left sided colon cancer (LsCC). We seek to confirm primary tumour location as an independent prognostic factor in locoregional colorectal cancer.
  
  
  
  All patients with stage I - III primary adenocarcinoma of colon were identified from the New South Wales (NSW) clinical cancer registry (2006-2013). Primary tumour location (RsCC vs LsCC) survival analyses were conducted using the Kaplan-Meier method, and adjusted hazard ratios for 5-year all-cause mortality (OS) and 5-year cancer specific mortality (CSS) were obtained using Cox proportional hazards regression.
  
  
  
  We identified 9509 patients including 5051 patients with RsCC and 4458 with LsCC. Patients with RsCC were more likely to be older, female, have a higher Charlson comorbidity index, and have worse tumour prognostic factors. In univariate analysis of all stages combined, those patients with RsCC had a worse overall survival (OS, HR 1.20 95% CI 1.11-1.29, p < 0.0001), although this was not significant in the multivariate analysis (HR 0.96 95% CI 0.89-1.04, p = 0.35). Stage I patients with RsCC had a trend to improved OS (multivariate HR 0.84 95% CI 0.69-1.01, p = 0.07) and a significantly improved CSS (multivariate HR 0.51 95% CI 0.35-0.75, p = 0.0006). In stage II patients with RsCC there was a significantly improved OS (multivariate HR 0.85 95% CI 0.75-0.98, p = 0.02) and CSS (multivariate HR 0.59 95% CI 0.45-0.78, p = 0.0002) compared to LsCC. In stage III patients, those with RsCC had a worse OS (multivariate HR 1.13 95% CI 1.01-1.26, p = 0.032) and a trend to worse CSS (multivariate HR 1.12 95% CI 0.94-1.33, p = 0.22).
  
  
  
  Primary tumour location is an important prognostic factor in locoregional colon cancer with an effect that varies by stage. RsCC is associated with lower all-cause mortality in stage II, and higher all-cause mortality in stage III.
authors.affiliation: Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia. Daniel.Brungs@health.nsw.gov.au.|School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia. Daniel.Brungs@health.nsw.gov.au.|Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia. Daniel.Brungs@health.nsw.gov.au.|CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia. Daniel.Brungs@health.nsw.gov.au.
authors.forename: Daniel
authors.initials: D
authors.lastname: Brungs
authors.affiliation: Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.|Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.|CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.
authors.forename: Morteza
authors.initials: M
authors.lastname: Aghmesheh
authors.affiliation: CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.|Medical Oncology Department, Liverpool Hospital, Sydney, NSW, Australia.|Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia.|School of Medicine, Western Sydney University, Sydney, NSW, Australia.|South Western Medical School, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: de Souza
authors.affiliation: CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.|Medical Oncology Department, Liverpool Hospital, Sydney, NSW, Australia.|Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Weng
authors.initials: W
authors.lastname: Ng
authors.affiliation: CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.|Medical Oncology Department, Liverpool Hospital, Sydney, NSW, Australia.|Ingham Institute for Applied Medical Research, Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Wei
authors.initials: W
authors.lastname: Chua
authors.affiliation: Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.|Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.|CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Carolan
authors.affiliation: Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.|Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.
authors.forename: Philip
authors.initials: P
authors.lastname: Clingan
authors.affiliation: Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.
authors.forename: Emma
authors.initials: E
authors.lastname: Healey
authors.affiliation: Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.
authors.forename: June
authors.initials: J
authors.lastname: Rose
authors.affiliation: Illawarra Cancer Centre, Wollongong Hospital, Wollongong, NSW, Australia.
authors.forename: Tameika
authors.initials: T
authors.lastname: Tubaro
authors.affiliation: Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia.|School of Biological Sciences, University of Wollongong, Wollongong, NSW, Australia.|CONCERT-Translational Cancer Research Centre, Sydney, NSW, Australia.
authors.forename: Marie
authors.initials: M
authors.lastname: Ranson
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000401:mortality* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009517:New South Wales; D011379:Prognosis; D012042:Registries; D016019:Survival Analysis
keywords: Colonic neoplasms/mortality; Colonic neoplasms/pathology; Neoplasm staging