Daijiworld Media Network - London

London, Aug 26: A study has found that long-course chemoradiotherapy (LCCRT) may offer better chances of preserving the rectum than short-course radiotherapy (SCRT) in selected patients with locally advanced rectal cancer who achieve a complete clinical response to treatment.

The research, published in Annals of Oncology, compared outcomes of 323 patients with locally advanced rectal adenocarcinoma who received total neoadjuvant therapy incorporating either long-course chemoradiotherapy or short-course radiotherapy.

Of the 323 patients, 247 received long-course chemoradiotherapy-based treatment, while 76 received short-course radiotherapy-based treatment. The median follow-up period was 31 months.

The researchers found that clinical complete response rates were similar between the two groups, at 44.5 per cent among patients receiving long-course treatment and 43.4 per cent among those receiving short-course radiotherapy.

However, a difference was observed in rectal organ preservation. At two years, the rectum was preserved in 40 per cent of patients in the long-course group, compared with 31 per cent in the short-course group.

The difference was greater among patients who achieved a complete clinical response and were managed through a "watch-and-wait" approach instead of undergoing immediate surgery. In this group, 89 per cent of patients treated with long-course chemoradiotherapy maintained rectal preservation at two years, compared with 70 per cent of those who received short-course radiotherapy.

The study also found a tendency towards lower local tumour regrowth following long-course treatment. Local regrowth at two years was reported in 19 per cent of patients in the long-course group compared with 36 per cent in the short-course group, although the difference did not reach statistical significance.

There were no significant differences between the two approaches in distant recurrence, disease-free survival or overall survival among patients managed with a watch-and-wait strategy. Two-year disease-free survival was 90 per cent in both groups, while overall survival was 99 per cent after long-course treatment and 100 per cent after short-course radiotherapy.

Long-course chemoradiotherapy generally involves radiation delivered over several weeks alongside chemotherapy, while short-course radiotherapy delivers radiation over five treatment sessions. Both are established approaches for treating locally advanced rectal cancer.

The possibility of preserving the rectum is particularly important for patients who respond exceptionally well to treatment. A watch-and-wait strategy can allow such patients to avoid or delay major rectal surgery, provided they undergo careful and regular monitoring.

The findings add to growing evidence on organ-preserving treatment strategies for rectal cancer. The American Society of Clinical Oncology has conditionally recommended long-course chemoradiotherapy over short-course radiotherapy when radiation is included in treatment for locally advanced rectal cancer.

However, short-course radiotherapy remains an important treatment option, with studies showing comparable long-term cancer outcomes in certain treatment settings. Doctors consider factors including tumour stage and location, the patient's overall health, expected treatment response and individual treatment goals before selecting an approach.

The researchers said their findings support long-course chemoradiotherapy followed by consolidation chemotherapy as a preferred total-neoadjuvant treatment approach for patients with locally advanced rectal cancer who specifically seek organ preservation.

They cautioned that the findings do not mean long-course treatment is appropriate for every rectal cancer patient. Further research, including prospective and randomised studies, is needed to determine the best treatment strategy for different groups of patients.