Abstract 119P
Background
To conduct a comparative analysis of the effectiveness of hypofractional and classical radiotherapy regimens in neoadjuvant chemoradiotherapy for locally advanced rectal cancer (LARC).
Methods
This study based on a retrospective analysis of a database in patients with LARC who underwent a course of neoadjuvant chemoradiotherapy followed by surgery. The patients were divided into two groups: the first (main) group, 104 patients who underwent a course of hypofractionated chemotherapy (4 Gy x 40 Gy 3 fractions per week) in combination with capecitabine 1650 mg/m2 in two doses. The second group (control group) included 120 patients who underwent a course of CRT in the classical fractionation regimen (2 Gy x 50-58 Gy 5 fractions per week) in combination with capecitabine 1650 mg/m2 in two doses. The main evaluated indicators are the frequency of pCR and cCR. Additional assessed indicators are the severity of early radiation toxicity, the frequency of local relapses, overall and disease-free survival.
Results
The study included 224 patients. The average duration of the CRT course in the study group was 22.56 (95% CI from 21.94 to 23.18) days, in the control group - 38.84 (95% CI from 38.12 to 39.54), p=0.0001. Radiation toxicity grade III and IV was registered in 5.75% of patients in the study group and in 6.41% of patients in the control group. pCR in the study groups was achieved in 19.23% and 15.83% of cases, respectively, p=0.504. The cCR in the studied groups was achieved in 25% and 18.3% of cases, respectively, p=0.226. The median time without progression was 37.6 months. In the main and control groups, local control rates were 91.34% and 88.3% respectively, p=0.954, HR=1.05 (95% CI 0.21 to 5.22). Five-year disease-free survival in the main group was 71.1% and in the control group 60.8%, respectively, p=0.353, HR=0.79 (95% CI 0.42 to 1.35). Five-year overall survival in the main and control groups were 81.7% and 79.2%, respectively, p=0.743, HR=0.87 (95% CI 0.39 to 1.92).
Conclusions
Thus, the hypofractionation regimen showed high antitumor efficacy and can be considered as an alternative and not inferior to the classical regimen in neoadjuvant CRT in patients with LARC.
Clinical trial identification
N/A
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
87TiP - Phase I expansion study of the tissue factor (TF)–targeting antibody-drug conjugate (ADC) XB002 as a single-agent and combination therapy in patients with advanced solid tumors (JEWEL-101)
Presenter: Mustafa Syed
Session: Poster Display
Resources:
Abstract
88TiP - A phase Ib study of HMBD-001, a monoclonal antibody targeting HER3, with or without chemotherapy in patients with genetic aberrations in HER3 signaling
Presenter: Nick Pavlakis
Session: Poster Display
Resources:
Abstract
93P - Efficacy and safety of fruquintinib (F) + best supportive care (BSC) vs placebo (P) + BSC in refractory metastatic colorectal cancer (mCRC): Asian vs non-Asian outcomes in FRESCO-2
Presenter: Daisuke Kotani
Session: Poster Display
Resources:
Abstract
94P - Sidedness-dependent prognostic impact of gene alterations in metastatic colorectal cancer in the nationwide cancer genome screening project in Japan (SCRUM-Japan GI-SCREEN)
Presenter: Takeshi Kajiwara
Session: Poster Display
Resources:
Abstract
95P - Interim results of a prospective randomized controlled study to compare the clinical outcomes of total neoadjuvant therapy vs long course chemoradiotherapy in locally advanced carcinoma rectum
Presenter: Sandip Barik
Session: Poster Display
Resources:
Abstract
96P - Tyrosine kinase inhibitor (TKI) plus PD-1 blockade in TKI-responsive MSS/pMMR metastatic colorectal adenocarcinoma (mCRC): Updated results of TRAP study
Presenter: Jingdong Zhang
Session: Poster Display
Resources:
Abstract
97P - Asian subgroup analysis of the phase III LEAP-017 trial of lenvatinib plus pembrolizumab vs standard-of-care in previously treated metastatic colorectal cancer (mCRC)
Presenter: Rui-Hua Xu
Session: Poster Display
Resources:
Abstract
98P - Real clinical impact of postoperative surgical complications after colon cancer surgery
Presenter: Toru Aoyama
Session: Poster Display
Resources:
Abstract
99P - Extended lymphadenectomy may not be necessary for MSI-H colon cancer patients after immunotherapy
Presenter: Rongxin Zhang
Session: Poster Display
Resources:
Abstract
100P - Identification of phenomic data in the pathogenesis of colorectal cancer: A UK biobank data analysis
Presenter: Shirin Hui Tan
Session: Poster Display
Resources:
Abstract