title: Survival among clinical stage I-III rectal cancer patients treated with different preoperative treatments: A population-based comparison.
abstract: Radical resection is regarded as the cornerstone of rectal cancer treatment. Preoperative (chemo)radiotherapy and adjuvant chemotherapy are often administered. This population-based study compares the survival in clinical stage I-III rectal cancer patients who received either preoperative radiotherapy, preoperative chemoradiotherapy or no preoperative therapy. As secondary research questions, the association of type of radical resection and adjuvant chemotherapy on survival is also investigated.
  
  
  
  Patients diagnosed between January 2006 and December 2011 with stage I-III rectal adenocarcinoma were retrieved from the Belgian Cancer Registry database. Multivariable Cox proportional hazards regression models were applied to evaluate the association of preoperative treatment, type of radical resection and use of adjuvant chemotherapy with survival, adjusting for the baseline characteristics age, gender, WHO performance status and clinical stage.
  
  
  
  A total of 5173 rectal cancer patients were identified. Preoperative treatment was as follows: none in 1354 (26.2%), radiotherapy in 797 (15.4%) and chemoradiotherapy in 3022 (58.4%) patients. The patient group who did not receive preoperative therapy or radiotherapy followed by radical resection had a lower observed survival compared to the patient group receiving preoperative chemoradiotherapy. The patient groups who underwent abdominoperineal excision and those receiving adjuvant chemotherapy had a worse observed survival compared to the patient group treated with sphincter-sparing surgery and no adjuvant therapy respectively. These effects were age-dependent. Multivariable analysis demonstrated similar findings for the observed survival conditional on surviving the first year since surgery.
  
  
  
  In this population-based study among clinical stage I-III rectal cancer patients treated with radical resection, a superior observed survival was noticed in the patient group receiving preoperative chemoradiotherapy compared to the patients groups receiving no or preoperative radiotherapy only, adjusting for case mix, type of radical resection and adjuvant chemotherapy. Additionally, higher adjusted observed survival was also detected for the patient groups with sphincter-sparing surgery or no adjuvant chemotherapy.
authors.affiliation: KU Leuven - University of Leuven, Department of Oncology, Herestraat 49, B-3000 Leuven, Belgium; University Hospitals Leuven, Department of Radiation Oncology, Herestraat 49, B-3000 Leuven, Belgium. Electronic address: ines.joye@uzleuven.be.
authors.forename: Ines
authors.initials: I
authors.lastname: Joye
authors.affiliation: Belgian Cancer Registry, Koningsstraat 215 bus 7, B-1210 Brussels, Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: Silversmit
authors.affiliation: Belgian Cancer Registry, Koningsstraat 215 bus 7, B-1210 Brussels, Belgium.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Van Eycken
authors.affiliation: KU Leuven - University of Leuven, Department of Oncology, Herestraat 49, B-3000 Leuven, Belgium; Belgian Cancer Registry, Koningsstraat 215 bus 7, B-1210 Brussels, Belgium.
authors.forename: Annelies
authors.initials: A
authors.lastname: Debucquoy
authors.affiliation: Belgian Cancer Registry, Koningsstraat 215 bus 7, B-1210 Brussels, Belgium.
authors.forename: Tamara
authors.initials: T
authors.lastname: Vandendael
authors.affiliation: KU Leuven - University of Leuven, Department of Abdominal Surgery, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Freddy
authors.initials: F
authors.lastname: Penninckx
authors.affiliation: KU Leuven - University of Leuven, Department of Oncology, Herestraat 49, B-3000 Leuven, Belgium; University Hospitals Leuven, Department of Radiation Oncology, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Karin
authors.initials: K
authors.lastname: Haustermans
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016896:Treatment Outcome
keywords: Chemoradiotherapy; Radiotherapy; Rectal neoplasm; Surgery; Survival