Results of Radiotherapy in Nasopharyngeal Cancer / 대한치료방사선과학회지

ABSTRACT

PURPOSE: The aim of this study was to assess the effectiveness, survival rate and complication of radiation therapy in nasopharyngeal cancer. MATERIALS AND METHODS: From January 1980 to May 1989, Fifty Patients who had nasopharyngeal carcinoma treated with curative radiation therapy at Kosin Medical Center were retrospectively studied. Thirty seven patients(74%) were treated with radiation therapy alone(Group I) and 13 patients (26%) treated with combination fo chemotherapy and radiation(Group II). Age distribution was 16-75 years(median45.8 years). In histologic type, squamous cell carcinoma was in 30 patients(60%), undifferentiated carcinoma in 17 patinets(34%), and lymphoepithelioma in 3 patients(6%). According to AJCC staging system, 4 patinets(8%) were in T1, 13 patients(2%) in T2, 20 patients(40%) in T3, 13 patients(26%) in T4 and 7 patients(14%) in N0, 6 patients(12%) in N1, 23 patients(46%) in N2, 14 patients (28%) in N3. Total radiaton dose ranges were 5250-9200 cGy(median 7355 cGy) in Group I and 5360-8400 cGy(median6758cGy) in Group II. Radiotherapy on 4-6MV linear accelerator and/or 6-12MeV electron in boost radiation was given with conventional thechnique to 26 patinets(52%), with hyperfractionation(115-120cGy/fr., 2times/day) to 16 patients(32%), with accelerated fractionation(160cGy/fr., 2 times/day) to 8 patients(16%). In Chemotherapy, 5 FU 1000mg daily for 5 consecutive days, pepleomycin 10mg on days 1 and 3, and cisplatin 100mg on day 1 were administered with 3 weeks interval, total 1 to 3 cycles(average 1.8cycles) prior to radiation therapy. Follow up duration was 6-140 months(mean58 months). Statistics was calculated with Chi-square and Fisher's exact test. RESULTS: Complete local control rates in Group I and II were 75.7%, 69.2%. Overall 5 year survival rates in Group I and II were 56.8%, 30.8%. Five year survival rates by histologic type in Group I and II were 52.2, 14.3% in squamous cell carcinoma an d 54.5%, 50% in undifferentiated carcinoma. Survival rates in Group I were superior to those of Group II though there were not statistically significant. In both group, survival rates seem to be increased according to increasing total dose of radiation up to 7500cGy, but not increased beyond it. There were not statistically significant differences in survival rates by age, , stage, and radiation tehchniques in both group. Twenty four patients (48%) experienced treatment failures. Complications were found in 12 patients(24%). The most common one was osteomyelitis(4 patients, 33.3%) involving mandible (3 patients) and maxilla(1patient). CONCLUSION: Chemotherapy in combination with radiotherapy was found to be not effective to nasopharyngeal cancer and the survival rate was also inferior to that of radiation alone group though it was statistically not significant due to small population in chemotherapy combined group.