Abstract 259P
Background
After local excision of early-stage rectal cancer, patients with risk factors are strongly recommended to undergo completion total mesorectal excision (TME), while adjuvant radiotherapy (ART) may be considered in patients who are medically inoperable or desire to avoid TME-related morbidities. However, the efficacy of ART compared to completion TME after local excision remains controversial. This study aimed to evaluate the efficacy of ART compared with TME.
Methods
This retrospective analysis included 244 patients diagnosed with pT1-2 rectal cancer on local excision (194 TME, 50 ART), eligible for either TME or ART, treated at two tertiary referral hospitals from January 1, 2000, to December 31, 2022. The primary endpoint was locoregional recurrence (LR) rate. Secondary endpoints included distant metastasis (DM) rate, overall survival (OS), and permanent stoma free rate. Outcomes between treatments were analyzed through propensity score matching (PSM) using logistic regression with a 2:1 match ratio and replacement.
Results
In the PSM analysis, the 2:1 matched cohort comprised 90 patients (60 TME, 30 ART). Among ART patients, 13 (26%) received capecitabine, 10 (20%) 5-fluouracil, and 7 (14%) oral uracil-tegafur plus leucovorin. After PSM, there was no statistical difference in clinicopathologic factors such as age, sex, tumor location, pT2 stage, grade 3, lymphovascular invasion and positive resection margins between TME and ART groups. Median F/U was 6.3 years (IQR 3.6 - 9.4) versus 5.3 years (IQR 3.4 - 7.4), respectively. LR recurrence was observed in 0 (0%) of TME patients and 1 (3%) of ART patients. DM metastasis was manifested in 6 (10%), 1(3%) with TME and ART respectively. Outcomes for TME and ART were not statistically different for LR recurrence, DM, and OS (all P > 0.05). After subgroup analysis in lower rectal cancer patients, there were no differences in outcomes (all P > 0.05) while permanent stoma was in 3 (5%), 0 (0%) with TME and ART, respectively.
Conclusions
The current study suggests that ART could be considered a viable alternative to completion TME for high risk patients after local excision of early-stage rectal cancer. ART can avoid the possibility of permanent stoma, considering the quality of life (QoL) in lower rectal cancer patients.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.