Practice patterns and outcomes of pediatric partial nephrectomy in the United States: Comparison between pediatric urology and general pediatric surgery

Summary Background In the United States, both pediatric urologists (PUROs) and general pediatric surgeons (GPSs) perform nephrectomies in children, with PUROs performing more nephrectomies overall, most commonly for benign causes. GPSs perform more nephrectomies for malignant causes. We questioned whether the same trends persisted for partial nephrectomy. Objective We hypothesized that PUROs performed more partial nephrectomies for all causes, including malignancy. Our primary aim was to characterize the number of partial nephrectomies performed by PUROs and GPSs. We also compared short-term outcomes between subspecialties. Study design We analyzed the Pediatric Health Information System (PHIS), a database encompassing data from 44 children's hospitals. Patients were ≤18 years old and had a partial nephrectomy (ICD-9 procedure code 554) carried out by PUROs or GPSs between 1 January, 2004 and June 30, 2013. Queried data points included surgeon subspecialty, age, gender, 3M™ All Patient Refined Diagnosis Related Groups (3M™ APR DRG) code, severity level, mortality risk, length of stay (LOS), and medical/surgical complication flags. Data points were compared in patients on whom PUROs and GPSs had operated. Statistical analysis included the Student t test, chi-square test, analysis of covariance, and logistic regression. Results Results are presented in the table. While PUROs performed the majority of partial nephrectomies, GPSs operated more commonly for malignancy. For surgeries performed for non-malignant indications, PURO patients had a shorter LOS and lower complication rate after controlling for statistically identified covariates. There was no difference in LOS or complication rate for patients with malignancy. Discussion A Pediatric Health Information System study of pediatric nephrectomy demonstrated PUROs performed more nephrectomies overall, but GPSs performed more surgeries for malignancy. The difference was less dramatic for partial nephrectomies (63% GPS, 37% PURO) than for radical nephrectomies (90% GPS, 10% PURO). PUROs performed more partial nephrectomies for benign indications (94% PURO, 6% GPS) at an even greater rate than nephrectomies (88% PURO, 12% GPS). As a national database study, there are a number of inherent limitations: applicability of results to non-participating hospitals, possibility of inaccurate data entry/coding, and lack of data points that would be relevant to the study. Conclusions While most partial nephrectomies in the United States are performed by PUROs, GPSs perform the majority of surgeries for malignancy. There is no difference in LOS or complication rate undergoing nephron-sparing surgery for malignant disease; however, PUROs had a shorter LOS and lower complication rate when operating for benign diseases. Table . Results summary of pediatric partial nephrectomy in the United States. PURO GPS p Partial nephrectomy for malignant disease N 77 132 Age (years ± SD) 5.31 ± 4.6 3.48 ± 3.4 0.001 % Male 35.1 38.6 0.607 Severity level 2.68 2.60 0.618 Mortality risk 1.38 1.36 0.851 LOS a (days ± SE) 7.45 ± 1.1 9.47 ± 0.9 0.162 Surgical complication rate a (%) 28.6 23.4 0.340 Partial nephrectomy for non-malignant disease N 1157 69 Age (years ± SD) 3.14 ± 4.6 4.99 ± 4.9 0.001 % Male 29.6 36.2 0.240 Severity level 1.60 1.65 0.396 Mortality risk 1.03 1.09 0.034 LOS b (days ± SE) 2.60 ± 0.70 3.70 ± 0.2 Surgical complication rate b (%) 4.4 17.4 a After controlling for statistically identified covariate, age. b After controlling for statistically identified covariates, age and mortality risk.