A preoperative MRI-based prediction model for biochemical failure after radical prostatectomy

Abstract

Abstract Objective: To propose and verify whether MRI-based model can reduce the incidence of postoperative biochemical failure (BF) in patients with PCa.Design: The center retrospectively analyzed 967 patients who accepted prostate bpMRI and radical prostatectomy (RP) from June 2018 to January 2020. Then, the included 446 patients were randomized into a research cohort (n=335) and validation cohort (n=111) at a ratio of 3:1. In addition to clinical variables, MRI models also include MRI parameters. The AUC of ROC and decision curve is analyzed.Main outcomes: Risk of postoperative BF, defined as persistent high or re-elevated PSA levels in patients with PCa who lack evidence of clinical recurrence.Result: Overall, in the research cohort (age, 69 [63 - 74] years) and the validation cohort (age, 69 [64 - 74] years), the incidence of postoperative BF was 22.39% and 27.02%, respectively. In the research cohort, the AUC of baseline model and MRI model were 0.780 and 0.857, respectively, with significant difference (P < 0.05). The results in the validation cohort were consistent (0.753 vs. 0.865, P < 0.05). At a 20% risk threshold, The false positive rate of MRI model was lower than that of baseline model (31% [95% CI, 9%-39%] vs 44% [95% CI, 15%-64%]), with the true positive rate has only decreased a little (83% [95% CI,63%-94%] vs 87% [95% CI, 75%-100%]). 32 of 100 RPs can been performed, with no raise in quantity of patients with missed BF.Conclusion: We developed and verified a MRI-based prediction model that predicts the incidence of BF in patients after RP through preoperative clinical variables and MRI-related variables. This model could be helpful for clinical work.