A Study of Relationship Between PPC(Probability of Primary Clearance: a multivariate modeling system predicting tumor clearance proposed by RTOG) and Survival in the Patients with Carcinoma of the Nasopharynx Following Radiation Therapy / 대한치료방사선과학회지

ABSTRACT

RTOG proposed a multivariate modeling system predicting the response of head and neck cancers to radiation therapy in 1984. The aim of this study was to verify whether PPC (Probability of primary clearance calculated by a multivariate modeling system) had any correlation with the survival in the patients with carcinoma of the nasopharynx following radiation therapy. Analysing 81 patients with carcinoma of the nasopharynx treated with radiotherapy between January 1, 1971 and December 31, 1983 at Yonsei University College of Medicine, Yonsei Cancer Center, the actuarial 5 year survival rate was 36% and median survival was 39 months. The survivals for Group 1 (27 who had more than 80% of PPC), Group 2 (20 who had between 71 and 80% of PPC), and Group 3 (29 who had less than 71% of PPC) were 66% (median survival months: more than 72), 27% (31), and 4% (12) respectively. There was a definite correlation between PPC and survival among the three groups.