Three-Dimensional Printing Assisted Laparoscopic Partial Nephrectomy vs. Conventional Nephrectomy in Patients With Complex Renal Tumor: A Systematic Review and Meta-Analysis

Three-Dimensional Physical Model in Urologic Cancer

Three-dimensional (3D) printing, as an evolving technology, enables the creation of patient-specific physical models with high precision; thus, it is widely used in various clinical practices, especially urologic cancer. There is an increasing need to clarify the contribution of 3D printing in the practice of urological cancer in order to identify various applications and improve understanding its benefits and challenges in clinical practice. Researches have focused on the use of 3D-printed models in patient and trainee education, surgical simulation, as well as surgical planning and guidance. This mini review will present the most recently published studies on the topic, including the applications of 3D-printed models, feasibility of performed procedures, possible simulated organs, application outcomes, and challenges involved in urologic cancer, to provide potential directions for future research.

Clinical implications of 3D printing technology in preoperative evaluation of partial nephrectomy

OBJECTIVES

Renal cancer is a common malignancy of the urinary system, and the partial nephrectomy is a common surgical modality for early renal cancer. 3D printing technology can create a visual three-dimensional model by using 3D digital models of the patient's imaging data. With this model, surgeons can perform preoperative assessment to clarify the location, depth, and blood supply of the tumor, which helps to develop preoperative plans and achieve better surgical outcomes. In this study, the R.E.N.A.L scoring system was used to stratify patients with renal tumors and to explore the clinical application value of 3D printing technology in laparoscopic partial nephrectomy.

METHODS

A total of 114 renal cancer patients who received laparoscopic partial nephrectomy in Xiangya Hospital from June 2019 to December 2020 were enrolled. The patients were assigned into an experimental group (n=52) and a control group (n=62) according to whether 3D printing technology was performed, and the differences in perioperative parameters between the 2 groups were compared. Thirty-nine patients were assigned into a low-complexity group (4-6 points), 32 into a moderate-complexity group (7-9 points), and 43 into a high-complexity group (10-12 points) according to R.E.N.A.L score, and the differences in perioperative parameters between the experimental group and the control group in each score group were compared.

RESULTS

The experimental group had shorter operative time, renal ischemia time, and postoperative hospital stay (all P<0.05), less intraoperative blood loss (P=0.047), and smaller postoperative blood creatinine change (P=0.032) compared with the control group. In the low-complexity group, there were no statistically significant differences between the experimental group and the control group in operation time, renal ischemia time, intraoperative blood loss, postoperative blood creatinine changes, and postoperative hospital stay (all P>0.05). In the moderate- and high- complexity groups, the experimental group had shorter operative time, renal ischemia time, and postoperative hospital stay (P<0.05 or P<0.001), less intraoperative blood loss (P=0.022 and P<0.001, respectively), and smaller postoperative blood creatinine changes (P<0.05 and P<0.001, respectively) compared with the control group.

CONCLUSIONS

Compared with renal tumor patients with R.E.N.A.L score<7, renal cancer patients with R.E.N.A.L score≥7 may benefit more from 3D printing assessment before undergoing partial nephrectomy.

Application of low-dose CT to the creation of 3D-printed kidney and perinephric tissue models for laparoscopic nephrectomy

PURPOSE

The aim of this study was to explore the feasibility of 3D printing of kidney and perinephric fat based on low-dose CT technology.

PATIENTS AND METHODS

A total of 184 patients with stage T1 complex renal tumors who underwent laparoscopic nephrectomy were prospectively enrolled and divided into three groups: group A (conventional dose kidney and perinephric fat 3D printing group, n = 62), group B (low-dose kidney and perinephric fat 3D printing, n = 64), and group C (conventional dose merely kidney 3D printing group, n = 58). The effective dose (ED), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were determined. The 3D printing quality was evaluated using a 4-point scale, and interobserver agreement was assessed using the intraclass correlation coefficient (ICC).

RESULTS

The ED of group B was lower than that of group A, with a decrease of 55.1%. The subjective scores of 3D printing quality in all groups were 3 or 4 points. The interobserver agreement among the three observers in 3D printing quality was good (ICC = 0.84-0.92). The perioperative indexes showed that operation time (OT), warm ischemia time (WIT), estimated blood loss (EBL), and laparoscopic partial nephrectomy (LPN) conversion to laparoscopic radical nephrectomy (LRN) in groups A or B were significantly less than those in group C. LPN was more frequent in group A and group B than in group C (all p < 0.017). There were no significant differences in perioperative indexes between group A and group B (all p > 0.017).

CONCLUSION

Low-dose CT technology can be effectively applied to 3D printing of kidney and perinephric fat and reduce the patient's radiation dose without compromising 3D printing quality. 3D printing of kidney and perinephric fat can significantly increase the success rate of LPN and decrease OT, WIT, and EBL.