Observational Study of Perioperative Chemotherapy in Gastric Cancer

Chile belongs to the countries with a high mortality rate due to gastric cancer, and this disease is the most frequent cause of cancer death in Chile. Despite of adequate surgery, survival rates are disappointing, with less than 60% of patients for all stages achieving to be alive at 5 years. This is due to the fact that frequently gastric cancer is diagnosed at an advanced stage. For locally advanced gastric cancer a multimodality treatment is recommended, with the alternatives of surgery followed by chemotherapy (asian approach), surgery followed by chemoradiation (US approach) and perioperative chemotherapy (european approach). These three strategies are valid standard treatment options and have shown to improve overall survival in stage IB to IVA gastric cancer.

Perioperative chemotherapy administered pre- and postoperatively, has shown to downstage the tumor, increase curative resection, progression free and overall survival.

For patients with potentially resectable gastric cancer staged T2 or higher or cN+, NCCN Guidelines recommend perioperative chemotherapy (category1). Chilean guidelines for gastric cancer state the alternative of perioperative chemotherapy, however this approach has not been used widely in public hospitals because lack of financial support.

Some gastric cancers overexpress HER2, and this subset of patients benefit from targeted therapy at an advanced stage. The proportions of patients with these molecular characteristics vary widely depending of the geographic area. The chilean population has been investigated in small series, but the incidence of HER2 positive gastric cancer is not known. We therefore plan to measure HER2 expression in all participating patients.

Inclusion criteria

• Histologically proven invasive carcinoma
• Age > 18 years.
• ECOG performance status 0 or 1.
• Hemoglobin > 9 g/dL
• Absolute neutrophil count > 1.5 x 109/L
• Platelet count > 100 x 109/L
• Creatinine < 1.5 ULN
• Creatinine clearance > 60 mL/min
• Serum bilirubin < 1.5 x ULN
• AST < 2.5 x ULN
• Women of child bearing potential: must agree to use an effective contraceptive method.
• Signed informed consent.

Exclusion criteria

• ECOG > 2.
• Pre-existing diarrhea uncontrolled with supportive care.
• Inability to swallow Xeloda tablets.
• History of mild-to-moderate renal insufficiency (creatinine clearance < 45 mL/min).
• Signs or symptoms of clinically significant hepatic dysfunction (bilirubin > 1.5 ULN, FA > 2.5 ULN, albumin < 2,5 g/dL).
• Significant cardiac dysfunction (LVEF < LLN)
• Presence of distant metastasis, including clinical signs of peritoneal carcinomatosis
• Symptomatic gastric retention or severe dysphagia with a caloric intake of < 1500 kcal/day
• Histology of lymphoma, GIST or neuroendocrine tumor
• Pregnant or breast-feeding women. Female patients must be postmenopausal, surgically sterile or they must agree to use an effective method of contraception.
• Any medical conditions that, in the investigator's opinion, would impose excessive risk to the patient. Examples of such conditions include congestive heart failure of Class III or IV of the NYHA classification, infection requiring parental or oral treatment, any altered mental status or any psychiatric condition that would interfere with the understanding of the informed consent.