Organ preservation following short-course radiotherapy for rectal cancer.

BACKGROUND: Non-operative management of rectal cancer is increasingly being used in selected patients. Most reports include patients treated with chemoradiotherapy (CRT) before inclusion into a Watch & Wait (W&W) programme. The aim of this study was to report outcomes from a single-centre W&W programme involving a large cohort of patients. METHODS: Patients treated with chemoradiotherapy (CRT) or short-course radiotherapy (SCRT) with or without chemotherapy, between 2008 and 2020, who showed signs of a clinical complete response (cCR) were reviewed. Patients were assessed using digital rectal examination, flexible endoscopy, carcinoembryonic antigen measurement, MRI, and CT imaging, discussed at the multidisciplinary tumour board meeting, and followed up in a dedicated W&W programme as from 2015. Outcomes including regrowth and 3-year survival (time to regrowth or death) were prospectively evaluated. RESULTS: Of 142 patients who were assessed, 88 fulfilled the criteria for cCR. Treatment before cCR included CRT, SCRT with chemotherapy, and SCRT alone in 16 (18 per cent), 28 (32 per cent), and 44 (50 per cent) patients, respectively. Patients treated with CRT and SCRT with chemotherapy had more advanced clinical T- and N-stage, compared with patients treated with SCRT alone (clinical T-stage > 2: 81 per cent and 89 per cent versus 47 per cent, respectively; clinical N-stage > 0: 75 per cent and 93 per cent versus 68 per cent, respectively). Overall rate of regrowth was 19 per cent, with 31 per cent, 21 per cent, and 14 per cent following CRT, SCRT with chemotherapy, and SCRT alone, respectively. Uni- and multivariable analyses evaluating the clinical parameters revealed no statistically significant associations with risk of local regrowth. All but one patient with regrowth underwent salvage surgery. The 3-year survival rate (death with regrowth as competing risk) was 93 per cent, with no significant difference between treatment groups. CONCLUSION: In this cohort of W&W patients, the vast majority received SCRT with or without chemotherapy and results consistent with previous W&W reports were obtained. No statistically significant differences in terms of regrowth rate were obtained when comparing CRT, SCRT with chemotherapy, and SCRT alone. SCRT can induce sustained cCR and may precede a W&W strategy.

[20-25 procent of patients with rectal cancer may be saved from a rectal resection]. / Organsparande behandling vid rektalcancer ­ färre opereras.

Besides clinical evaluation, all patients with rectal cancer must be examined with CT of the chest and abdomen to assess the presence of metastases, pelvic MRI to stage the tumour locally, and if possible, colonoscopy to detect synchronous lesions. The recommended treatment is then discussed at an MDT conference and neoadjuvant radio- or chemoradiotherapy given according to national guidelines. A new digital rectal examination (DRE) and proctoscopy, CT and pelvic MRI should be performed around six weeks after treatment. The purpose is to detect potential new metastases and to assess tumour response after treatment. It is crucial to do a second MDT with careful MRI evaluation to detect a possible clinical complete response. If the post-treatment MRI shows a complete or near complete response, corresponding to clinical findings on DRE and endoscopy, the patient should be offered a prospective watch and wait protocol in a dedicated institution. With proper management of patients with rectal cancer, 20-25 procent may be saved from a rectal resection and the potential risk of a permanent stoma.