Role of radiotherapy in the treatment of rectal cancer in older patients

Abstract

Striking a balance between cancer treatment and patient-centred care is becoming ever more important in older patients with rectal cancer as the population is ageing. The treatment decision made by the modern multidisciplinary colorectal team will recommend pre-operative chemo-radiotherapy followed by surgery for advance rectal cancer and surgery alone for early rectal cancer, as the "standard of care" is surgery. However, an alternative non-surgical treatment option should be consider for older patients with rectal cancer as the surgical harm can far outweigh the potential benefits. There is published evidence that mortality is higher with increasing age. An alternative treatment option to surgery when patients are not suitable or refusing surgery is to offer them external beam radiotherapy (EBRT) or chemo radiotherapy (EBCRT). A proportion of these patients can achieve a clinical complete response (cCR) which enable adoption of 'watch and wait' strategy to avoid surgery. However, a third of patients who achieved initial cCR can develop local regrowth within the first two years. This require salvage surgery which reduces their chance of organ preservation. Contact X-ray brachytherapy (CXB) or High Dose Rate Endo Brachy Therapy (HDREBT) boost following external beam radiotherapy can improve the initial cCR rate and reduce the risk of local regrowth. Those patients with persistent residual cancer or regrowth after brachytherapy boost following EBCRT or EBRT can have salvage surgery later without compromising their chance of cure. Therefore, patients should be fully aware of their treatment options and have 'a choice' when deciding and consenting their treatment.

Keywords: Brachytherapy; Chemo-radiotherapy; Local regrowth; Non-surgical; Rectal cancer; Watch and wait.