Cancer - Prostate(구연) (E-107) 정낭 침범 전립선암에서 수술 후 방사선치료의 시기에 따른 예후의 차이 울산대학교 서울아산병원 비뇨의학교실 김휘우, 홍준혁, 김청수, 안한종 Purpose This study aimed to evaluate the impact of timing of postoperative radiotherapy (RT) on survival outcomes in pathologic T3b prostate cancer (PCa). Methods This study is a single-center retrospective study with patients who had diagnosed as pathologic T3b PCa after radical prostatectomy (RP) and received postoperative RT after RP. Patients were divided into three groups: Patients who received postoperative RT without evidence of biochemical recurrence (BCR) (Early salvage RT), patients who received RT after BCR (Salvage RT), and patients who received RT after more than 6 months of androgen deprivation therapy (ADT) after BCR (Delayed RT). Patients who were treated with only postoperative ADT were designated as control group. Radiographic progression-free survival (rPFS) and cancer specific survival (CSS) were analyzed with Cox-proportional model and Kaplan-Meier model after propensity score matching. Result A total of 273 patients who underwent RP and diagnosed as pathologic T3b PCa from 2007 to 2017 were analyzed after propensity score matching. Overall median rPFS and CSS were 36.8 months and 51.4 months after secondary treatment, respectively. Early salvage group showed significantly less radiographic progression (HR 0.070, p=0.009) and cancer-specific death (log rank p = 0.008) than other groups. There are no differences in rPFS and CSS between Salvage or Delayed RT group compared with ADT only group. Kaplan-Meier analysis showed better PFS and CSS in Early salvage RT group. In addition, comparing to the group who were followed up without any secondary treatment, Early salvage RT group noted less BCR (HR 0.114, p<0.001). Conclusion Clinicians should consider early salvage RT with patients who were confirmed as pathologic T3b PCa after RP. keywords : Prostate cancer, Radiotherapy, Survival