DDD score for renal tumor: An intuitive and comprehensive anatomical scoring system to access the outcomes of retroperitoneal laparoscopic partial nephrectomy

Abstract

Objective To present a DDD scoring system in assessing the complexity and outcomes of retroperitoneoscopic nephron‐sparing surgery for kidney tumor. Methods We retrospectively evaluated 232 patients who underwent retroperitoneoscopic nephron‐sparing surgery between January 2013 and September 2017 for a renal tumor. Both the DDD score and RENAL score were used to classify the tumors. The DDD score consisted of the maximal tumor diameter inside the kidney, the maximal tumor depth into the medulla or collecting system and the minimal distance from the tumor to the main renal vessels. Results The DDD scoring systems were significantly associated with warm ischemia time (P = 0.007) and estimated blood loss (P = 0.017). There was an insignificant positive correlation between the DDD score and the operative time (P = 0.051). Meanwhile, the RENAL score had a significant correlation with the decreasing value of the estimated glomerular filtration rate. Patients with high or moderate DDD scores had a 13.6‐fold or 8.4‐fold risk of overall complications than those with low DDD scores, respectively (all P < 0.05). As for RENAL score, patients with moderate scores had a 2.9‐fold risk of overall complications compared with patients in the low scores group (P = 0.004). In the receiver operating characteristic curve analysis, the DDD score had the greatest area under the curve for overall complications (area under the curve 0.625, P = 0.009), which was more than the RENAL score (area under the curve 0.620, P = 0.013). Conclusions The DDD score is an intuitive renal tumor scoring system that is more effective than the RENAL score in complexity assessment, and marginally better in prediction of the risk of overall complications of retroperitoneal laparoscopic nephron‐sparing surgery.

The DDD score outperforms the RENAL score in predicting high‐grade renal cell carcinoma

“…The predictive capacity of the DDD score for surgical complexity in partial nephrectomy is slightly superior to that of the RENAL score. 19 In the present study, we found that the DDD score was a predictor of the Fuhrman grade in RCC patients. Studies have shown that as the size of the tumor increases, there is a markedly higher likelihood of high-grade versus low-grade histology.…”

“…A comprehensive explanation of the scoring system is provided in Figure 1. 19 Categorical variables are described as numbers and proportions. Continuous variables are described as medians and interquartile ranges (IQRs).…”

“…The green lines depict D3, indicating the distance from the masses to the main renal vessels. 19 calibrate the nomogram; other analyses were performed using SPSS (version 24.0, IBM, Armonk, NY). All tests were twotailed, and a p value <0.05 was considered to indicate statistical significance.…”

Editorial Comment to DDD score for renal tumor: An intuitive and comprehensive anatomical scoring system to access the outcomes of retroperitoneal laparoscopic partial nephrectomy

“…5 The present study by Zhang et al introduces a novel anatomical scoring method with the goal of improving on the current classification systems. 6 The DDD scoring system includes three key surgically relevant anatomical features of renal tumors. The scores derived were significantly associated with warm ischemia time, estimated blood loss and overall complications rate from nephron-sparing surgery.…”

“…The present study by Zhang et al . introduces a novel anatomical scoring method with the goal of improving on the current classification systems . The DDD scoring system includes three key surgically relevant anatomical features of renal tumors.…”