Background

There is an increasing interest in patients deciding to opt for the ‘Watch-and-Wait’ regime(WW) worldwide after achieving a clinical complete response(cCR) from neoadjuvant chemo-radiotherapy(NACRT). However, there is still uncertainty to see how successful chemo-radiotherapy is in treating rectal cancer alone.

Method

This retrospective analysis of rectal carcinoma patients diagnosed at BHRUT from 5/2013 - 6/2020. Electronic health records were utilised with the primary outcomes being, Median overall survival, Disease Free Survival, Recurrence Rate, R0 Salvage Surgery Rate and Distant failure. 

Results

78/506 rectal cancer patients under long-course chemo- radiotherapy. 72/276 NACRT achieved a complete response. 63 patients were selected for ‘Watch-and-Wait’ after a median of 97[88-124]days, whereas 11 opted for surgery. Overall survival amongst ‘Watch-and-Wait’ patients’ was 85.7% with a median overall survival of 1103[717-1484] days. The recurrence rate of these patients was 27.0%(16) of which the 5 developed distant metastases. Disease free survival in recurrences was 253 days after which 70.6% underwent salvage surgery -83.3% and 16.7% per- formed with R0 and R1 margins respectively. 9/72 patients opted for surgery. 7/9(77.8%) patients were found to have no residual tumour.

Conclusion

27% of WW patients in this real world cohort developed recurrence and 5/17 failed distantly e highlighting the need for personalised decision-making and further understanding and identification of risk factors associated with increased recurrences.

Impact statement

The results show that organ preservation with WW is an acceptable alternative but recurrence and metastatic rates are in-line with previous series. The incidence of salvage resections yielding R1 rates was 16.7%. Our data is a real world reflection and not registry based and hence may present a larger R1 resection rate than recently published series.