Development and validation of a novel nephrometry nomogram model predicting perioperative outcomes of partial nephrectomy for T 1b renal masses / 中华泌尿外科杂志

ABSTRACT

Objective:To analyze the correlation between R. E.N.A.L., PADUA, C-index, DAP scoring system and the efficacy and safety of nephron-sparing surgery (NSS) for T 1b renal tumors, and to construct a nomogram model to predict the efficacy and safety of surgery by combining multiple parameters. Methods:The data of 80 patients with stage T 1b renal tumor who received NSS from March 2020 to July 2021 in Changhai Hospital of Naval Military Medical University were retrospectively analyzed. There were 59 males and 21 females, aged (56.9±10.2) years old. The tumor diameter was (4.7±0.9) cm, with 40 cases on the left and 40 on the right sides. Tumors were located in the upper/lower pole in 46 cases and in the middle in 34 cases. The tumors were located in 59 cases laterally, 21 cases medially, and 74 cases were bulging, 16 cases endogenous. There were 53 round tumors, 18 lobular tumors, and 9 irregular tumors. One case underwent open surgery, 43 cases underwent laparoscopic surgery, and 36 cases underwent robotic surgery.42 cases underwent transperitoneal approach, and 38 cases underwent retroperitoneal approach. The composite outcome (MIC) achieved by all three indicators, including negative surgical margins, warm ischemia time <20 min, and no serious complications, was used as the main indicator to evaluate the efficacy and safety of surgery. Secondary indicators were operation time, intraoperative blood loss, postoperative hospital stay, postoperative creatinine changes and hemoglobin changes. Relevant risk factors were analyzed by logistic regression, and a nomogram model for predicting surgical efficacy and safety was constructed. Receiver operating characteristic(ROC) curves were used to compare the predictive power of the nomogram model with other scoring systems. Results:Univariate logistic regression analysis showed that PADUA and R. E.N.A.L. scores were risk factors for MIC achievement( OR=1.419, P=0.038; OR=1.358, P=0.038). However, C-index and DAP were not risk factors for MIC achievement( P>0.05). The results of correlation analysis showed that R. E.N.A.L. score was significantly correlated with postoperative hemoglobin decrease(R 2=0.197). PADUA score was significantly correlated with postoperative hospital stay(R 2=0.186). C-index was significantly correlated with postoperative creatinine increase(R 2=-0.221). DAP was significantly associated with operation time (R 2=0.192). The results of univariate logistic regression analysis showed that body mass index ( OR=1.257, P=0.025), tumor morphology ( OR=18.741, P=0.005), longitudinal location of tumor ( OR=1.992, P=0.038), the relationship between tumor and collection system ( OR=4.886, P=0.002) were risk factors for MIC attainment. A nomogram prediction model was constructed by combining these indicators with the Mayo adhesive probability (MAP) index. The ROC curve showed that the area under the curve (AUC) of the nomogram model and R. E.N.A.L. score, PADUA score, C-index, and DAP were 0.834, 0.645, 0.643, 0.526, and 0.593, respectively. The nomogram model had the highest predictive power for T 1b renal tumors achieving MIC. Conclusions:In the renal tumor scoring system, PADUA and R. E.N.A.L. scores can predict whether the MIC of T 1b renal tumor NSS is achieved or not. The nomogram model composed of patient body mass index, tumor shape, longitudinal position of tumor, relationship between tumor and collecting system and MAP can better predict whether the MIC of T 1b renal tumor NSS is achieved or not.