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
529P - Ramucirumab plus docetaxel after combination chemoimmunotherapy in patients with non-small cell lung cancer: A prospective observational study
Presenter: Tadaaki Yamada
Session: Poster Display
Resources:
Abstract
530P - MYC recruits tumor-associated macrophage to sustain metastatic malignancy of lung adenocarcinoma micropapillary subtype through epigenetic reprogramming
Presenter: Xuming Song
Session: Poster Display
Resources:
Abstract
531P - Effect of combinational targeted therapy for AXL and ATR against malignant mesothelioma cells
Presenter: Soichi Hirai
Session: Poster Display
Resources:
Abstract
532P - The changes of the serum SMRP levels is useful to predict the antitumor efficacy of ipilimumab plus nivolumab combination therapy in patients with malignant pleural mesothelioma
Presenter: Taiichiro Otsuki
Session: Poster Display
Resources:
Abstract
533P - Efficacy in the elderly NSCLC patients in SCORPION study: Phase II study of DTX plus RAM following platinum-based chemotherapy plus ICIs
Presenter: Teppei Yamaguchi
Session: Poster Display
Resources:
Abstract
534P - DSC2 promotes the proliferation, metastasis and drug resistance of lung cancer by activating the PI3K/AKT pathway
Presenter: Qi Li
Session: Poster Display
Resources:
Abstract
535P - Alteration in NKX2-1 CN reshapes the oncogenic, immunologic, and prognostic landscapes in NSCLC
Presenter: Herdee Gloriane Luna
Session: Poster Display
Resources:
Abstract
536P - The evaluation and long-term outcome of pulmonary metastasectomy for osteosarcoma: A 20-year experience of Shanghai Rujin Hospital
Presenter: Zhusheng Zhang
Session: Poster Display
Resources:
Abstract
537P - The impact of treatment-free interval on patient outcome after pulmonary metastasectomy for sarcoma
Presenter: Po-Kuei Hsu
Session: Poster Display
Resources:
Abstract
538P - First-line chemoimmunotherapy for metastatic thymic carcinoma
Presenter: Victoria Andreas
Session: Poster Display
Resources:
Abstract