This multicenter, prospective, single-arm study evaluates a novel streamlined pathway for men at high risk of clinically significant prostate cancer (csPCa) identified by the USTC model (probability ≥0.60). Under general anesthesia, participants undergo MRI/ultrasound fusion targeted biopsy; the cores are immediately analyzed by frozen section hematoxylin-eosin staining and rapid immunohistochemistry. If csPCa is confirmed intraoperatively, laparoscopic radical prostatectomy is performed during the same anesthesia session. The primary aims are to determine the diagnostic concordance between intraoperative rapid pathology and definitive paraffin pathology, the positive surgical margin rate at 12 months, and perioperative safety. The study enrolls 150 participants across 12 Chinese hospitals and is expected to provide evidence supporting an efficient, PET-independent, one-stage diagnostic-therapeutic strategy for clinically significant prostate cancer.

Study Design and Setting This is a prospective, multicenter, single-arm, open-label clinical study conducted in 12 tertiary hospitals in China that have established multidisciplinary prostate cancer teams.

Screening and Enrollment Male patients with clinical suspicion of prostate cancer undergo serum total PSA testing and 3.0T multiparametric MRI. Prostatic volume is measured to calculate prostate-specific antigen density (PSAD), and the index lesion is scored using PI-RADS v2.1. These parameters are entered into the USTC online nomogram (https://ustcprostatecancerprediction.shinyapps.io/dynnomapp/) to generate a predicted probability of clinically significant prostate cancer (csPCa). Patients with a predicted probability ≥0.60, who meet all eligibility criteria (PSA 4-100 ng/mL, at least one PI-RADS ≥3 lesion, ECOG 0-1, no contraindication to general anesthesia or radical prostatectomy, and no evidence of metastasis), are fully informed and asked to provide written consent. Enrolled participants proceed directly to the interventional pathway.

Intervention Under general anesthesia, MRI/ultrasound fusion targeted biopsy (2-4 cores from the index lesion) is performed. The cores are immediately submitted for frozen section hematoxylin-eosin staining and rapid immunohistochemistry (key antibodies: P63, P504s, CK5/6). A pathologist provides a report within 30-60 minutes.

If csPCa is diagnosed intraoperatively, the patient is repositioned and laparoscopic radical prostatectomy is completed under the same anesthesia session.

If rapid pathology returns benign tissue, atypical small acinar proliferation, high-grade prostatic intraepithelial neoplasia, or is non-diagnostic, the procedure is stopped; only the biopsy is performed, and further management follows standard care.

Endpoints and Follow-up Primary endpoints: Positive Predictive Value (PPV) of intraoperative frozen section combined with rapid immunohistochemistry for clinically significant prostate cancer (csPCa) Secondary endpoints: ① Positive surgical margin rate; ② Agreement rate between intraoperative rapid pathology and postoperative paraffin-embedded pathology according to the ISUP grading system. ② Biochemical recurrence rates at 3, 6, and 12 months postoperatively (defined as two consecutive postoperative serum PSA levels ≥ 0.2 ng/mL with an interval of at least 3 weeks; cumulative incidence will be calculated). ③ Incidence of perioperative complications. ③ Incidence of serious adverse events (SAEs). ④ Intraoperative blood loss (mL) and perioperative (intraoperative to 30 days postoperatively) transfusion rate. ⑤ Rehospitalization rate within 30 days postoperatively. ⑥ Urinary continence recovery rate at 3, 6, and 12 months postoperatively.

Follow-up visits occur at 30 days, 3, 6, and 12 months post-procedure. All data are captured via paper case report forms and managed centrally

Inclusion Criteria:

① Patients with clinically suspected prostate cancer based on examination (e.g., DRE or PSA testing); ② Patients who have undergone serum tPSA testing and mpMRI; ③ 4 ng/mL ≤ tPSA < 100 ng/mL; ④ Patients with a csPCa risk probability of ≥0.60 as assessed by the clinical prediction model (https://ustcprostatecancerprediction.shinyapps.io/dynnomapp/); ⑤ The patient has no significant contraindications for prostate biopsy or radical prostatectomy.

Exclusion Criteria:

① No complete serum tPSA test or mpMRI scan; ② tPSA < 4 ng/mL or ≥ 100 ng/mL; ③ Based on assessment by a clinical prediction model, the patient's probability of csPCa is < 0.60; ④ Patients with a history of multiple biopsies showing no evidence of clinically significant prostate cancer; ⑤ Patients in poor general health who cannot tolerate a biopsy; ⑥ Patients with severe bleeding disorders or those currently undergoing anticoagulant therapy.