Postoperative Radiotherapy for Locally Advanced Gastric Cancer

Lee, Myung Za; Chun, Ha Chung; Kim, In Soon; Chung, Te June

Abstract

PURPOSE: Radical gastrectomy is main treatment of gastric cancer. But the result is not satisfactory with surgery alone. Most of pattern of failure remain locoregional recurrence. To improve 5 year survival postoperative chemotherapy with or without radiotherapy has been used. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. MATERIAL AND METHOD: From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adjuvant radiotherapy with 36Gy or more were evaluated. Median age was 60 years(range 28-66 yrs). Patients were followed from 3 to 133 months with median follow up of 48 months. Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively. Chemotherapy was given to all patients except two.
RESULTS
Five-year overall survival and disease-free survival rate were 36.6% and 33.6%, respectively. Prognostic factor affecting survival were assessed. High ratio of involved/dissected lymph node, signet ring histology showed poor prognosis with statistical significance. Presence of residual tumor after surgery, stageIV, split course of radiation therapy, age, number of involved lymph node, number of lymph node dissection and grade of tumor affected survival without statistical significance. Type of chemotherapy did not affect survival.Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and E-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six patients(8.8%) had weigh loss more than 10%.
CONCLUSION
Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high. Five-year surival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival. To evaluate role of radiation prospective randomized study employing chemotherapy alone and chemotherapy plus radiation is necessary. Futhermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored.