Clinicoradiological parameters predicting operative difficulty in laparoscopic partial nephrectomy for renal tumors.

Introduction: The number of renal tumors amenable to laparoscopic surgery is rising, both, due early detection by improved imaging techniques and due to progressive improvements in minimal access surgery. Conversion to open surgery, which is a significant event, can be minimized by proper case selection. We assessed the pre-operative factors that can predict the operative difficulty and can help in case selection, thus avoiding complications and reducing the chances of conversion to open.

Methods: One hundred and sixteen patients (73 males and 43 females) with the mean age of 50.78 ± 14.2 years, meeting the inclusion criteria underwent transperitoneal laparoscopic partial nephrectomy (LPN). Various clinical, anthropometric, radiological, and pathological parameters were recorded. Intraoperative difficulty was assessed and graded on a scale of 1 (easiest) to 4 (most difficult or open conversion) by an independent observer to calculate the difficulty score, which along with the other parameters of operative difficulty, was used to calculate the difficulty scale. Significant parameters on the univariate analysis, were subjected to a multivariate analysis, to find parameters that can predict the operative difficulty.

Results: The mean age was 52 ± 14.29 years, mean size was 4 ± 1.04 cm, male:female ratio was 1.6:1, most of the tumors were exophytic (60%) and anteriorly located (62%) and had a mean perinephric fat surface density (PnFSD) of 6446.026 ± 2244 surface density pixel units (SDPU). On the univariate analysis, age >60 years, Eastern Cooperative Oncology Group performance score >1, presence of perinephric fat stranding, increased PnFSD (>10,000 SDPU), large tumor size (>4 cm), hilar/posterior location, endophytic tumors and higher clinical stage were significantly associated with intraoperative difficulty. However, on the multivariate analysis, no single factor could independently predict intraoperative difficulty in LPN for Renal tumors.

Conclusion: It is difficult to predict the intra-operative difficulty during LPN. Feasibility of LPN should be based on multiple factors rather than a single factor.