Abstract 270P
Background
The management of rectal cancer is becoming increasingly complex with multiple surgical and oncological treatment options. Outcomes are less commonly reported for patients undergoing short course radiotherapy (25 Gy in 5 fractions) and planned delay. This treatment option may be suitable for frailer patients with non metastatic rectal cancer (NMRC). It can also be used for those with metastatic rectal cancer (MRC) for control of the primary tumour. The aim of this study was to assess outcomes and toxicity for these two cohorts at the Edinburgh Cancer Centre.
Methods
A local database of all patients undergoing short course rectal radiotherapy from 2017-2021 was filtered to include only those who had completed 25 Gy in 5 fractions followed by a planned delay. Two cohorts of patients were analysed separately, NMRC and MRC at presentation. Primary outcome was overall survival. Secondary outcomes included subsequent surgical management, radiological response to treatment and toxicity. Simple descriptive analysis was achieved by excel and Kaplan Meier curves were created using ‘R’ programming software.
Results
A total of 96 patients were included in the study (74 NMRC and 22 MRC). Median follow up was 44.9 months and 36.1 months in NMRC and MRC cohorts respectively. Median Overall Survival was 31.2 months in NMRC cohort and 20.2 months in MRC cohort. 61 (85%) Patients in NMRC had a radiological response to treatment versus 9 (41%) patients in the MRC cohort. 51(69%) patients in NMRC had subsequent radical surgery compared to 3 (14%) patients in MRC cohort. 14 (63%) patients in the metastatic cohort had >1 cycle of chemotherapy. 7 (9.5%) patients in NMRC cohort developed grade 3 toxicity or above, compared to 1(4.5%) patient in MRC cohort.
Conclusions
Short course radiotherapy and delay is a treatment which offers potential cure for those who proceed to subsequent surgery, and a long period of local control for those who do not. This treatment seems to be tolerated well and achieves high levels of response in borderline surgical candidates. The survival benefit in metastatic patients will be influenced by the decision to give systemic treatments, but short course radiotherapy offers a good opportunity for local pelvic control.
Legal entity responsible for the study
Edinburgh Cancer Centre, NHS Lothian.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.