Intergroup 0116 (SWOG 9008)- phase III trial of postoperative adjuvant radiochemotherapy for high risk gastric and gastroesophageal junction adenocarcinoma: Evaluation of efficacy and radiotherapy treatment planning
Presenter: S. Smalley
The management of patients with locally advanced gastric adenocarcinoma (ACA) remains a major challenge for oncologists. Complete surgical resection has been the standard care for this group of patients. However, the long-term outcome has been dismal. In this Intergroup study, the researchers reported results of the phase III randomized trial evaluating postoperative combined modality therapy (CMT) versus postoperative observation (OBS) in completely resected ACA of stomach.Materials and Methods:
- A total of 603 patients (47 ineligible) were accrued and randomized to either the OBS or CMT arm.
- CMT arm consisted of 1 cycle of 5-FU based chemotherapy before, 2 cycles during and 2 cycles following local radiiotherapy (RT) to a dose of 45 Gy in 25 fractions.
- RT fields and treatment plans were evaluated and required approval prior to treatment by the protocol coordinator.
- CMT achieved significant better 5-year local control than OBS, 93% vs. 81% (p < 0.001).
- 5-year relapse-free survival was significantly better in CMT arm, 40% vs. 22% (p < 0.0001).
- Patients treated with CMT had a significantly better 5-year overall survival than the observed patients, 42% vs. 23% (p < 0.01).
- Primary tumor treatment portal deviations were observed in 21% of patients on the initial review.
- CMT significantly improved relapse-free and overall survival of patients who had completely resected high-risk gastric cancer.
- Even in the presence of a written protocol, quality control of RT treatment planning remained a major concern.
- Future trials utilizing RT must continue to implement strict quality assurance programs to maintain protocol compliance prior to RT administration.
- Quality control remains a major concern in radiation oncology.