To investigate the risk factors for retrograde ureteral stenting failure in the treatment of malignant external ureteral obstruction.

The clinical data of patients with malignant ureteral obstruction caused by compression or invasion of non-urological cancers and who underwent retrograde ureteral stenting in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2021 to January 2024 were retrospectively collected. Patients were divided into two groups according to whether retrograde ureteral stenting failure. Univariate and multivariate Logistic regression analysis were used to analyze the correlation between retrograde ureteral stenting failure and preoperative predictors such as age, BMI, and nephrostomy status, primary cancer type, nature, previous treatment history, preoperative hemoglobin value, albumin value, serum creatinine level, tumor marker level, urine leukocytes, urinary occult blood, urine culture, ureteral lateralization (left, right, bilateral), ureteral obstruction level (abdominal segment, pelvic segment, bladder wall segment, bladder invasion), grade of hydronephrosis, pelvic wall invasion, abdominal wall invasion, urinary fistula, intestinal fistula and so on.

Among the 80 cases of MEUO that underwent RUS, 26 cases (32.5%) failed. Univariate Logistic regression analysis showed that the risk factors for RUS failure were the primary cancer simultaneously invading the bladder, bladder wall segment, and pelvic segment, the presence of pelvic radiation inflammation, preoperative serum albumin value of less than 35 g/L, and preoperative urine leukocyte positive (P<0.05). The multivariate Logistic regression analysis indicated that the primary cancer simultaneously invading the bladder, bladder wall segment, and pelvic segment (P=0.016, OR=3.818, 95%CI: 1.279-11.398), the presence of pelvic radiation inflammation (P=0.044, OR=3.004, 95%CI: 1.030-8.760) would increase the risk of RUS failure.

The primary cancer simultaneously invades the bladder, bladder wall segment, and pelvic segment, and the presence of pelvic radiation inflammation were independent risk factors for predicting the failure of RUS in patients with MEUO.