Endourology & Stone Disease(구연) (NP-043) Renal function is associated with prognosis in stent-change therapy for malignant ureteral obstruction 울산대학교 의과대학 울산대학교병원 비뇨의학과교실 윤지형, 박세준, 박성찬, 문경현, 전상현, 권택민 Purpose: So far, studies on stent failure have been extensively studied. However, only a few studies have addressed outcomes of stent failure and impact on prognosis. So, we performed this study to investigate the risk factors for predicting stent failure, and evaluated its impact on prognosis. Materials and Methods: Between January 2002 and March 2017, we retrospectively reviewed 117 consecutive patients who underwent retrograde ureteral stenting and exchanging at least one 3-month for malignant ureteral obstruction. The patients were classified according to pre-stenting chronic kidney disease (CKD) stage. To verify the difference in mean eGFR during the follow-up period according to CKD stage, data were assessed (pre-stenting, 3, 6, 9 and 12 months post-stenting). The factors affecting the stent failure were analyzed using logistic regression model. Overall survival was estimated, and the prognostic significance of each variable was estimated using Cox proportional-hazards regression modeling. Results: The most common causes of malignancy were gynecologic tumors (uterus 52.9% and ovary 8.6%), followed by colon cancer (21.4%). Before stenting, 91 were CKD stage 1-3 and 26 were CKD stage 4-5. The two groups were significantly different only in pre-stenting eGFR, bilateral obstruction and pre-stenting pyuria. After stenting, eGFR was significantly elevated in the first 3 months, but was maintained thereafter from 53.4 to 57.8 ml/min/1.73 m2 for one year. Among117 patients, stent failure occurred in 30 patients (25.6%) and there was no difference between the groups. Pre-stenting pyuria (p=0.035) and complications (p<0.001) were significant predictors of stent failure. There were 79 deaths in all, 56 in CKD 1-3 group and 23 in CKD 4-5. In the multivariate analysis predicting patient OS, pre-stenting eGFR (HR 0.97, p=0.001) and post-stenting disease progression (HR 26.74, p<0.001) were significant factors. Conclusions: Internal ureteral stenting was effective for maintaining renal function in malignant ureteral obstruction. However, it did not restore the renal function, which is related to the prognosis of the patients. Therefore, to improve the patient's renal function and prognosis, it is very important to recognize quickly and treat patients who need a stenting. keywords : Renal function, internal stenting, prognosis