Feasibility and outcome of radical prostatectomy following inductive neoadjuvant therapy in patients with suspicion of rectal infiltration

Objective: To determine the feasibility and outcome of radical prostatectomy (RP) following neoadjuvant therapy (NAT) in patients with initial inoperable, rectum-infiltrating cT4 prostate cancer (PCa).

Methods: From 01/2018 to 12/2020, 26 patients with clinical (DRE) or radiographical (mpMRI) suspicion of rectum infiltrating PCa at diagnosis and NAT prior to RP were retrospectively identified from our prospective institutional database. Two patients were still inoperable after NAT. Downsizing was administered for at least 20 weeks and RP was performed after excluding ongoing rectal infiltration.

Results: At diagnosis, median PSA was 42.5 ng/ml (IQR: 23.0-66.1). Inductive NAT consisted of androgen deprivation therapy (ADT) in combination with chemotherapy (n = 9) or without chemotherapy (n = 14). Median preoperative PSA was 0.93 ng/ml (IQR: 0.24-0.40). Median time from NAT to RP was 6 months (IQR: 5-7). Two patients were still inoperable after NAT. Of 24 patients undergoing RP, abortion of surgery due to inoperability was observed in 2 patients (8.4%), demonstrating a total failure rate of NAT in 4 out of 26 patients (15.4%). One patient suffered a rectal injury with consecutive colostomy (4.2%). No Clavien-Dindo complication Grade IV or V were observed. Urinary continence was achieved in 16 patients (84.2%). Sufficient erection for sexual intercourse was present in 2 patients (10.5%). All patients received adjuvant ADT with or without radiation therapy. Median PSA at 13 months was 0.08 ng/ml (IQR: 0.01-0.74).

Conclusion: RP of initially rectum infiltrating PCa is feasible and safe after inductive NAT, however complications rates tend to be higher compared to standard RP.