Avoidance of Overtreatment of Rectal Cancer by Selective Chemoradiotherapy: Results of the Optimized Surgery and MRI-Based Multimodal Therapy Trial

J Am Coll Surg. 2020 Oct;231(4):413-425.e2. doi: 10.1016/j.jamcollsurg.2020.06.023. Epub 2020 Jul 19.

Abstract

Background: Neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer carries a high risk of adverse effects. The aim of this study was to examine the selective application of nCRT based on patient risk profile, as determined by MRI, to find the optimal range between undertreatment and overtreatment.

Study design: In this prospective multicenter observational study, nCRT before total mesorectal excision (TME) was indicated in high-risk patients with involved or threatened mesorectal fascia (≤1 mm), or cT4 or cT3 carcinomas of the lower rectal third. All other patients received primary surgery.

Results: Of the 1,093 patients, 878 (80.3%) were treated according to the protocol, 526 patients (59.9%) underwent primary surgery, and 352 patients (40.1%) underwent nCRT followed by surgery. The 3-year locoregional recurrence (LR) rate was 3.1%. Of 604 patients with clinical stages II and III, 267 (44.2%) had primary surgery; 337 (55.8%) received nCRT followed by TME. The 3-year LR rate was 3.9%, without significant differences between groups. In patients with clinical stages II and III who underwent primary surgery, 27.3% were diagnosed with pathological stage I.

Conclusions: The results justify the restriction of nCRT to high-risk patients with rectal cancer classified by pretreatment MRI. Provided that a high-quality MRI diagnosis, TME surgery, and standardized examination of the resected specimen are performed, nCRT, with its adverse effects, costs, and treatment time can be avoided in more than 40% of patients with stage II or III rectal cancer with minimal risk of undertreatment. (clinicaltrials.gov NCT325649).

Trial registration: ClinicalTrials.gov NCT01325649.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma / diagnosis
  • Carcinoma / mortality
  • Carcinoma / pathology
  • Carcinoma / therapy*
  • Case-Control Studies
  • Chemoradiotherapy, Adjuvant / adverse effects
  • Chemoradiotherapy, Adjuvant / economics
  • Chemoradiotherapy, Adjuvant / standards*
  • Disease-Free Survival
  • Female
  • Follow-Up Studies
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Medical Overuse / economics
  • Medical Overuse / prevention & control*
  • Middle Aged
  • Neoadjuvant Therapy / adverse effects
  • Neoadjuvant Therapy / economics
  • Neoadjuvant Therapy / standards*
  • Neoplasm Recurrence, Local / epidemiology*
  • Neoplasm Recurrence, Local / prevention & control
  • Neoplasm Staging
  • Practice Guidelines as Topic
  • Proctectomy
  • Prospective Studies
  • Rectal Neoplasms / diagnosis
  • Rectal Neoplasms / mortality
  • Rectal Neoplasms / pathology
  • Rectal Neoplasms / therapy*
  • Rectum / diagnostic imaging
  • Rectum / pathology
  • Rectum / surgery

Associated data

  • ClinicalTrials.gov/NCT01325649