Correlation between male pelvic and soft tissue parameters based on three-dimensional reconstruction and the difficulty of robot-assisted radical prostatectomy.

OBJECTIVE: To investigate the correlation between male pelvic osseous and soft tissue parameters obtained from preoperative three-dimensional (3D) computed tomography (CT) reconstruction and the surgical difficulty of robot-assisted radical prostatectomy (RARP). METHODS: The study enrolled 324 patients with localized or locally advanced prostate cancer who underwent RARP. Based on preoperative CT images, 3D reconstruction was performed using Mimics Medical 21.0 software to accurately measure anatomical parameters. The K-means clustering algorithm was adopted for unsupervised anatomical subtyping of the patients; least absolute shrinkage and selection operator (LASSO) regression was used for feature dimensionality reduction, followed by multivariate linear and logistic regression analyses to identify the independent predictors of each outcome. Finally, a nomogram prediction model was constructed with OT as the endpoint event. RESULTS: K-means clustering divided the 324 patients into two anatomical subgroups,. Multivariate analysis revealed that the independent predictors of OT. PD was the only independent predictor of EBL. The independent predictors of SM were Gleason score,nerve-sparing procedure, APM and angle δ. The nomogram model for OT constructed based on 7 pelvic anatomical predictors had an apparent area under the curve (AUC) of 0.945. The calibration curve demonstrated good consistency between the predicted and actual observed probabilities. CONCLUSION: Pelvic anatomical parameters derived from 3D CT reconstruction can effectively predict the surgical difficulty of RARP. Among these parameters, pelvic spatial dimensional parameters mainly affect OT, PD independently predicts the risk of intraoperative bleeding, while positive SM is jointly driven by tumor biological characteristics, surgical decisions and anatomical factors. The nomogram model constructed with 7 pelvic anatomical parameters exhibits good discrimination and calibration, which can serve as an objective and quantitative decision-making tool for preoperative assessment of surgical difficulty and formulation of individualized surgical strategies for RARP.