Combination Chemotherapy, Cetuximab and Radiation for Patients With Localized Gastric Cancer

Overview

RATIONALE: Radiotherapy is currently the most efficient way to induce pathologic responses, which are associated with a favorable prognosis in localized tumors. Novel radiotherapy techniques are associated with significantly less toxicity than traditional radiation protocols and permit to avoid the toxicity to adjacent organs. Established chemotherapy regimens, such as cisplatin and capecitabine, and monoclonal antibodies, such as cetuximab, can block tumor growth in different ways. Giving radiation therapy together with cisplatin and cetuximab before surgery aims to induce a pathological response and improve the prognosis after surgery. PURPOSE: This phase I trial is studying the side effects and best dose of radiation therapy when given together with cisplatin and cetuximab in treating patients who are undergoing surgery for locally advanced gastric cancer.

OBJECTIVES: Primary • To determine the maximum tolerated dose of radio-chemo-immunotherapy - in patients with localized or locally advanced gastric cancer Secondary * To determine the efficacy, as measured by major histopathological response rates (tumor regression grade 1 and 2) * Metabolic response * Secondary resectability * R-0 resection rate * Surgical morbidity * Toxicity * Overall survival * Time to local and systemic progression after R0-resection * Feasibility OUTLINE: Prospective, multicenter, open-label dose escalating phase Ib trial During induction chemo-immuno-therapy, patients receive cetuximab IV over 1-2 hours on days 1, cisplatin IV over 1 hour on day 1 and capecitabine twice daily per os from the evening of day 1 to the morning of day 15. Treatment repeats every 3 weeks for up to 3 courses in the absence of disease progression or unacceptable toxicity. Radiotherapy will start after the end of the third cycle of chemotherapy and be performed concomitantly with weekly cetuximab and cisplatin. Cohorts of 3-6 patients receive escalating doses of radiotherapy (levels of 36/39.6/45 Gy) until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which maximum 3 of 12 patients experience dose-limiting toxicity. Gastric resection should be performed within 4-6 weeks after completion of neoadjuvant treatment. 4-6 weeks after surgery, a further 3 cycles of chemo-immuno-therapy will be administered if the patient has recovered from surgery and the treatment is considered as feasible by the investigator. For note: Cisplatin may be replaced by oxaliplatin during induction chemotherapy and postoperative chemotherapy. In case if oxaliplatin is used to replace cisplatin during induction chemotherapy, replacement of cisplatin by oxaliplatin during radio-chemo-immunotherapy may also be considered by the investigator. Capecitabine may be replaced by infusional 5-FU on day 1-5 every 21 days in case of contraindications to capecitabine. In case if both cisplatin and capecitabine are to be replaced, 4 cycles of FOLFOX-6 (d-l leucovorin, followed by 5-FU bolus and a continuous infusion of over 46 hours every 2 weeks should be administered in combination with cetuximab). Patients undergo tumor tissue and blood sample collection periodically for biological studies. Samples are analyzed for major histopathological response. After completion of study treatment, patients are followed periodically for at least 5 years.