Surgery helps avoid castrate-resistant state in men with metastatic prostate cancer

In men with metastatic prostate cancer, prior radical prostatectomy (RP) appears to reduce the risk of developing a castrate-resistant state, as compared with radiation therapy (RT), according to a recent study. Previous RP also seems to improve overall survival (OS).

“To date, level 1 evidence comparing the efficacy of RP and RT for localized disease is lacking,” the researchers said. “The results from our study are consistent with [previous] findings and show that the type of local treatment used before metastasis might influence disease behavior after metastasis, and this is usually unaddressed during patient counseling about local treatment options.”

Electronic health records of 1,338 patients were retrospectively assessed. All participants had previously undergone either RT or RP for local disease, and all had subsequently progressed to metastatic cancer. Outcomes included further progression to castration-resistant prostate cancer (CRPC) and OS, calculated from the date of metastasis diagnosis.

At baseline, 54 percent (n=744) of patients had had prior RT exposure, while the remaining 46 percent (n=644) had previously been treated with RP. Men in the RP group were significantly younger and had better performance status than RT comparators, though propensity score matching attenuated such differences. [Front Urol 2022;doi:10.3389/fruro.2022.891798]

Over a median follow-up duration of 38.6 months, RP patients had a median time to metastasis of 78.9 months. Meanwhile, RT patients developed metastasis after 73.1 months. This was calculated during a median RT follow-up of 26.0 months. In the RP and RT patients who eventually progressed to CRPC, the median time to progression from metastasis diagnosis was 20.0 and 13.1 months, respectively.

In the propensity score-matched cohort, Cox proportional hazards regression analysis revealed that RT significantly correlated with a 31-percent jump in the risk of progression to CRPC from metastasis, as compared with RP (hazard ratio [HR], 1.36, 95 percent confidence interval [CI], 1.07–1.61; p=0.009).

RP also proved superior to RT in terms of OS, with corresponding median OS estimates of 38.6 and 27 months (p<0.0001). Cox modelling confirmed that mortality risk was much higher in men who had previously received RT (HR, 1.35, 95 percent CI, 1.1–1.65; p=0.003).

“Real-world data indicated that patients with metastatic prostate cancer who had undergone prior RP might have a lower risk of developing a castrate-resistant state and improved OS compared to patients who had received RT,” the researchers said, noting that “significant amount of bias limits validity and strength of our findings.”

“Whether type of local treatment influence the disease behavior remains open question and should be answered only within randomized trial,” they added.