Single Patient Classifier (SPC) Prediction for Stage II and III Advanced Gastric Cancer

Inclusion Criteria: 1. Sample providers criteria * Male and female adult patients aged 19 years or over * Postoperative patients with gastric cancer invading the submucosal layer and having 3 or more lymph nodes metastasis or who with gastric cancer infiltration of muscularis propria and lymph node metastasis (stage II and III advanced gastric cancer patients, 8th of the AJCC) * Patients who have not received neoadjuvant chemotherapy and radiotherapy * Patients with pathological record and clinical information after surgery from archived FFPE(formalin-fixed paraffin-embedded) samples between 2005 and 2010 * Patients who have not been included in discovery clinical trial and confirmatory clinical trial * Patients who have undergone a radical gastrectomy and who show no evidence of residual tumors as observed with the unaided eye or through a microscope 2. Sample criteria * The FFPE tumor specimens in storage have a tumor amount of at least 20% and therefore can be tested. * The quantity (not less than 400ng) and quality (A260/280 of not less than 1.8) of RNA are sufficient for analysis. Exclusion Criteria: 1. Sample providers criteria * Male and female patients aged less than 19 years * Postoperative patients with gastric cancer invading the mucosa and submucosal layer and having less than 3 lymph nodes metastasis or who with gastric cancer infiltration of muscularis propria without lymph node metastasis (stage II and III advanced gastric cancer patients, 8th of the AJCC) * Patients who have received neoadjuvant chemotherapy or radiotherapy * Patients without pathological record and clinical information after surgery from archived FFPE samples between 2005 and 2010 * Patients who have been included in discovery clinical trial and confirmatory clinical trial * Patients with residual tumors after surgery 2. Sample criteria * The FFPE tumor specimens in storage have a tumor amount of less than 20% and therefore cannot be tested * The quantity and quality of RNA are not sufficient for analysis