Laparoscopic conversion to open surgery in radical nephrectomy and tumor thrombectomy: causal analysis, clinical characteristics, and treatment strategies

BACKGROUND: We aimed to explore the causal analysis, clinical characteristics and treatment strategies of laparoscopic conversion to open approach (LCTOA) in radical nephrectomy and tumor thrombectomy. METHODS: We included all patients with Mayo level I–III renal tumors with inferior vena cava (IVC) tumor thrombus who underwent laparoscopic radical nephrectomy and tumor thrombectomy as the first choice from May 2015 to July 2019. RESULTS: There were 70 cases of renal tumor with IVC tumor thrombus treated with a laparoscopic approach as the first choice; 31 Mayo level I, 30 Mayo level II, and 9 Mayo level III. A completely laparoscopic approach was performed in 51 cases (72.9%), and 19 cases (27.1%) underwent active or passive LCTOA. The LCTOA group had higher median preoperative serum creatinine (110.0 μmol/L vs 92.0 μmol/L; P = 0.026), longer postoperative hospital stay (9 days vs 7 days; P = 0.008), longer median operation time (374 min vs 311 min; P = 0.017), higher median intraoperative hemorrhage volume (1300 vs 600 ml; P = 0.020), and higher proportion of male patients (94.7% vs 66.7%; P = 0.016) vs the completely laparoscopic group, respectively. Although preoperative serum creatinine and gender were risk factors in the univariate analysis, multivariate analysis revealed no independent risk factors for LCTOA. We divided the reasons for LCTOA into active conversion and passive conversion; 4 (21.1%) cases underwent active conversion, and 15 (78.9%) underwent passive conversion. Most of the patients undergoing passive conversion had multiple concurrent risk factors, among which perirenal adhesion (30.9%), organ invasion (16.4%), and IVC adhesion (25.5%) were the most common. Fourteen (73.7%) cases underwent renal treatment, and 5 (26.3%) cases underwent tumor thrombus treatment. CONCLUSIONS: The LCTOA group had a higher median preoperative serum creatinine concentration, longer hospital stay, longer median operation time, and higher median intraoperative hemorrhage volume. However, none of the predictors in our study was an independent risk factor for LCTOA. Perirenal adhesion, organ invasion, and IVC adhesion were the most common causes of LCTOA. Considering the limitations of this study, studies with large sample sizes are required to validate our conclusions.