Definitive radiotherapy or chemoradiotherapy for distal rectal cancer with early stage of cT1-2N0

Treatment Options for Distal Rectal Cancer in the Era of Organ Preservation

OPINION STATEMENT

The introduction of total mesorectal excision into the radical surgery of rectal cancer has significantly improved the oncological outcome with longer survival and lower local recurrence. Traditional treatment modalities of distal rectal cancer, relying on radical surgery, while effective, take their own set of risks, including surgical complications, potential damage to the anus, and surrounding structure owing to the pursuit of thorough resection. The progress of operating methods as well as the integration of systemic therapies and radiotherapy into the peri-operative period, particularly the exciting clinical complete response of patients after neoadjuvant treatment, have paved the way for organ preservation strategy. The non-inferiority oncological outcome of "watch and wait" compared with radical surgery underscores the potential of organ preservation not only to control local recurrence but also to reduce the need for treatments followed by structure destruction, hopefully improving the long-term quality of life. Radical radiotherapy provides another treatment option for patients unwilling or unable to undergo surgery. Organ preservation points out the direction of treatment for distal rectal cancer, while additional researches are needed to answer remaining questions about its optimal use.

Long-term outcomes of patients with poor prognostic factors following transanal endoscopic microsurgery for early rectal cancer

AIM

Management of early rectal cancer following transanal microscopic anal surgery poses a management dilemma when the histopathology reveals poor prognostic features, due to high risk of local recurrence. The aim of this study is to evaluate the oncological outcomes of such patients who undergo surgery with total mesorectal excision (TME), receive adjuvant chemo/radiotherapy (CRDT/RT) or receive close surveillance only (no further treatment).

METHODS

We identified patients with poor prognostic factors-pT2 adenocarcinoma, poor differentiation, deep submucosal invasion (Kikuchi SM3), lymphovascular invasion, tumour budding or R1 resection margin-between 1 September 2012 and 31 January 2020 and report their oncological outcomes.

RESULTS

Of the 53 patients, 18 had TME, 14 had CRDT and 14 had RT; seven patients did not have any further treatment. The median follow-up was 48 months, 12 developed recurrence and six died. Overall, 5-year survival (OS) was 88.9% and disease-free survival (DFS) was 79.2%. Compared to the surgical group, in which there were eight recurrences and two deaths, there were zero recurrences or deaths in the CRDT group, log-rank test P = 0.206 for OS and P = 0.005 for DFS. The 5-year survival rates in the RT and surveillance only groups were OS 78.6%, DFS 85.7% and OS 71.5%, DFS 71% respectively. TME assessment in the surgical group revealed Grade 3 quality in seven of the 16 available reports.

CONCLUSION

These findings support the strategy of adjuvant CRDT as first line treatment for patients undergoing transanal endoscopic microsurgery for early rectal cancer with poor prognostic factors on initial histological assessment.