The Results of Definitive Radiation Therapy and The Analysis of Prognostic Factors for Non-Small Cell Lung Cancer

Chang, Seung Hee; Lee, Kyung Ja; Lee, Soon Nam

Abstract

PURPOSE: This retrospective study was tried to evaluate the clinical characteristics of patients, patterns of failure, survival rates, prognostic factors affecting survival, and treatment related toxicities when non-small cell lung cancer patients was treated by definitive radiotherapy alone or combined with chemotherapy. MATERIAL AND METHODS: We evaluated the treatment results of 70 patients who were treated by definitive radiation therapy for non-small cell lung cancer at the Department of Radiation Oncology, Ewha Womans University Hospital, between March 1982 and April 1996. The number of patients of each stage was 2 in stage I, 6 in stage II, 30 in stage III-A, 29 in stage III- B, 3 in stage IV. Radiation therapy was administered by 6 MV linear accelerator and daily dose was 1.8-2.0 Gy and total radiation dose was ranged from 50.4 Gy to 72.0 Gy with median dose 59.4 Gy. Thirty four patients was treated with combined therapy with neoadjuvant or concurrent chemotherapy and radiotherapy, and most of them were administered with the multi-drug combined chemotherapy including etoposide and cisplatin. The survival rate was calculated with the Kaplan-Meier methods.
RESULTS
The overall 1-year, 2-year, and 3-year survival rates were 63%, 29%, and 26%, respectively. The median survival time of all patients was 17 months. The disease-free survival rate for 1-year and 2-year were 23% and 16%, respectively. The overall 1-year survival rates according to the stage was 100% for stage I, 80% for stage II, 61% for stage III, and 50% for stage IV. The overall 1-year, 2-year, and 3-year survival rates for stage III patients only were 61%, 23%, and 20%, respectively. The median survival time of stage III patients only was 15 months. The complete response rates by radiation therapy was 16% and partial response rate was 50%. Thirty patients (43%) among 70 patients assessed local control at initial 3 months follow-up duration. Twenty four (80%) of these 30 patients was possible to evaluate the pattern of failure after achievement of local control. And then, treatment failure occured in 14 patients (58%); local relapse in 6 patients (43%), distant metastasis in 6 patients (43%) and local relapse with distant metastasis in 2 patients (14%). Therefore, 16 patients (23%) were controlled of disease of primary site with or without distant metastases. Twenty three patients (46%) among 50 patients who were possible to follow-up had distant metastasis. The overall 1-year survival rate according to the treatment modalities was 59% in radiotherapy alone and 66% in chemoirradiation group. The overall 1-year survival rates for stage III patients only was 51% in radiotherapy alone and 68% in chemoirradiation group which was significant different. The significant prognostic factors affecting survival rate were the stage and the achievement of local control for all patients at univariate- analysis. Use of neoadjuvant or concurrent chemotherapy, use of chemotherapy and the achievement of local control for stage III patients only were also prognostic factors. The stage, pretreatment performance status, use of neoadjuvant or concurrent chemotherapy, total radiation dose and the achievement of local control were significant at multivariate analysis. The treatment-related toxicities were esophagitis, radiation pneumonitis, hematologic toxicity and dermatitis, which were spontaneously improved, but 2 patients were died with radiation pneumonitis.
CONCLUSION
The conventional radiation therapy was not sufficient therapy for achievement of long-term survival in locally advanced non-small cell lung cancer. Therefore, aggressive treatment including the addition of appropriate chemotherapeutic drug to decrease distant metastasis and preoperative radiotherapy combined with surgery, hyperfractionation radiotherapy or 3-D conformal radiation therapy for increase local control are needed.