Chemotherapy Versus Chemotherapy Plus Chemoradiation As Neoadjuvant Therapy For Resectable Gastric Adenocarcinoma: A Multi-institutional Analysis
*Casey J Allen1, *David T Pointer2, *Alisa N. Blumenthaler1, *Rutika J. Mehta2, *Sarah E. Hoffe2, *Bruce D. Minsky1, *Grace L. Smith1, *Mariela Blum1, *Paul F. Mansfield1, *Naruhiko Ikoma1, *Prajnan Das1, *Jaffer Ajani1, *Sean P. Dineen2, Jason B. Fleming2, *Brian D. Badgwell1, *Jose M Pimiento2
1University of Texas MD Anderson Cancer Center, Houston, TX;2H. Lee Moffitt Cancer Center, Tampa Bay, FL
OBJECTIVE(S): We compare neoadjuvant chemotherapy (CT) to neoadjuvant chemotherapy plus chemoradiation (CRT) for patients with gastric adenocarcinoma (GA).
METHODS: Utilizing data from two high-volume cancer centers (one routinely provides CT, the other CRT), we analyzed patients who underwent surgery for localized GA from 1/1/2000-12/31/2017. CT regimens were used according to standard during treatment period. We compared propensity matched cohorts based on age, sex, race, histology, and clinical stage.
RESULTS: 405 patients (age 62±12y, 58% male, 56% white) were analyzed. 231 (57%) received CRT and 174 (43%) received CT. Groups differed based on histopathologic characteristics including preoperative stage (p=0.013). To control for these differences, propensity matched cohorts of 113 CT and 113 CRT patients were compared. CRT had similar frequencies of R0 resections to CT (93% vs 91%, p=0.81), but higher rates of complete pathologic response (15% vs 4%, p=0.003) and lower pathologic stage (p=0.002). Completion of intended perioperative therapy occurred in 70% of CT and 93% of CRT patients (p<0.001). Median DFS was 45mo (95%CI: 20-70) in the CT group and 113mo (95%CI: 75-151) in the CRT group (p=0.018). Median OS was 53mo (95%CI: 30-77) versus 120mo (95%CI: 101-138); p=0.015.
CONCLUSIONS: In this multi-institutional comparison of neoadjuvant CT and CRT for resectable GA, CRT is associated with higher rates of completed perioperative therapy, higher rates of complete pathologic response, lower pathologic stage, and improved survival.
Back to 2021 Abstracts