ABSTRACT
Objective To explore the feasibility of 3D printing technique combined with intra-operative ultrasound for locating completely endophytic renal tumor in laparoscopic nephron-sparing surgery. Methods Fifteen patients with completely endophytic renal tumor, who underwent 3D printing technique combined with intra-operative ultrasound assisted localization of laparoscopic partial nephrectomy from Mar. 2014 to Mar. 2016, received CT image 3D reconstruction and 3D printing kidney model using Formlab Form1+ 3D printer before operation. Among 15 patients aging (55.7±10.5) years, 11 patients were male and 4 were female; the tumor diameter was (2.8±1.0) cm; and 3 cases were ventral and 12 were dorsal, all had solitary tumors. The clinical data, including intra-operative blood loss, warm ischemia time, post-operative pathology and surgical margins, and post-operative renal function, were statistically analyzed in this study. Results Laparoscopic partial nephrectomy was successfully carried out in all cases:the average operation time was (105.0±20.6) min, the average warm ischemia time was (22.8±3.5) min, and the mean intra-operative blood loss was (87.3±15.8) mL. No case received blood transfusion during or after operation, and the average post-operative hospital stay was (6.7±1.0) days. No obvious complication occurred after operation. The surgical margins were all negative. Post-operative pathology confirmed that 1 3 patients were with clear cell renal cell carcinoma, and 2 with papillary renal cell carcinoma. Patients were followed up for (23.7±11.8) months, and no continuous deterioration of renal function or tumor recurrence was found. Conclusion Pre-operative 3D printing technique for patients with completely endophytic renal tumor can help to determine the tumor location and adjacent relationship, reducing the risk of surgery by guiding operation scheme. Meanwhile, propaganda and education using 3D printing kidney model can improve patients’ cognition to surgery and simplify pre-operative conversation process. Furthermore, utilizing intra-operative ultrasound to optimize tumor resection scheme can reduce the damage to the renal vessels and collection system, maximizing the clinical benefit by ensuring negative margin and renal function reservation.