Quality-of-Life Analysis of a Phase II Randomised Controlled Trial Comparing Three-Dimensional Conformal Radiotherapy and Intensity-Modulated Radiotherapy in Locally Advanced Rectal Cancer.

Aims: Neoadjuvant radiotherapy is an integral part of the management of locally advanced rectal cancer. Radiotherapy can be delivered using three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) techniques. We herein compare the quality-of-life (QOL) outcomes of patients who received radiotherapy using these techniques in a randomised trial.

Materials and methods: A phase II randomised trial was conducted in patients with locally advanced rectal cancer. Patients staged as T3-4, N (any), or circumferential resection margin at risk were eligible. All patients underwent neoadjuvant chemoradiotherapy with 50.4 Gy given in 28 fractions with concomitant fluorouracil or capecitabine. Patients were randomly allocated, in a 1:1 ratio, to 3DCRT or IMRT planning techniques. QOL, a secondary objective of the study, was evaluated using the European Organisation for Research and Treatment for Cancer (EORTC) Quality of Life Questionnaire (QLQ) C30 and QLQ CR29 questionnaires at baseline, during the final week of radiotherapy and, at six months after radiotherapy. The impact of the treatment arm on QOL scores was evaluated using analysis of covariance after adjusting for the preintervention scores.

Results: 94 patients were accrued between October 2014 and March 2020. The trial was terminated early due to futility of the primary outcome, acute gastrointestinal toxicity, at interim analysis. Eighty-six (91%) patients completed the baseline questionnaire and one other timepoint of assessment. Median follow-up was 1.9 years. Overall, both during the final week of radiotherapy and at six months, emotional functioning had improved, but physical, role, and social functionings had declined compared to that at baseline. At baseline, there was no difference in QOL scores between the two arms. During the final week of radiotherapy, the IMRT arm was associated with better adjusted mean physical (p = 0.04) and role functioning (p = 0.01) scores.

Conclusion: IMRT is associated with limited QOL benefits compared to 3DCRT in patients undergoing neoadjuvant chemoradiotherapy for locally advanced rectal cancer.