A phase II trial of preoperative chemotherapy and chemoradiotherapy for potentially resectable adenocarcinoma of the stomach (RTOG 99–04)

Abstract

4019 Background: Postoperative chemoradiotherapy is now considered standard treatment following curative resection of gastric cancer in selected patients. As the value of preoperative chemoradiotherapy is undetermined, this study was designed primarily to evaluate if a complete pathological response (pathCR) rate of 20% is possible employing this strategy, with feasibility, survival, tolerance and rate of curative resection as secondary endpoints. Methods: Patients having localized biopsy proven gastric adenocarcinoma (EUS T2–3, any N, M0) were eligible. A negative laparoscopic evaluation was required. Patients received 2 cycles of infusional 5-fluorouracil (200 mg/m2/d) on days 1–21, leucovorin (20 mg/m2) on days 1,7,14, and 21 and Cisplatin (20 mg/m2) on days 1–5. This was followed by concurrent radiation (45 Gy in 25 Fx) and infusional 5-fluorouracil (300 mg/m2/d) Monday to Friday and weekly Taxol (45 mg/m2) in weeks 1–5. Surgery was subsequently attempted in 5–6 weeks. Results: Forty-nine patients have been entered and 43 (12% IB, 37% II, 52% III) are evaluable. The pathCR and R0 resection rates are 27% and 77% respectively. Grade 4 toxicity (CTC 2.0) was experienced by 21% of patients with no treatment-related deaths. Radiotherapy planning and surgical technique according to protocol occurred in 44% and 49% of patients respectively. A total feasibility evaluation of this strategy is pending. Conclusions: These data suggest that the primary endpoint of the study was met (>20% pathCR rate). This study forms a basis for a future comparison of pre vs. post operative chemoradiotherapy strategies for localized resectable gastric cancer. (Supported by NCI) No significant financial relationships to disclose.