Predicting castration-resistant prostate cancer after combined androgen blockade

Abstract

This study analyzed ⁹⁹Tcm-MDP bone scans and investigated factors influencing early-stage castration resistance in prostate cancer (CRPC) patients with bone metastasis. We retrospectively analyzed clinical data from 92 patients with bone metastatic prostate cancer treated with maximal androgen blockade. Patients were imaged with ⁹⁹Tcm-MDP bone scan to detect metastases, and prostate specific antigen (PSA) values were measured regularly. Before treatment, 464 total bone metastases were detected in the 92 patients, with pelvic bone metastases accounting for about 30.6% of the total. After combined androgen blockade treatment, median CRPC occurrence time was 23 months. A longer time to reach the lowest PSA value was an independent predictor of early-onset CRPC (occurrence <1 year after treatment). Our findings suggest that ⁹⁹Tcm-MDP bone scans are useful for diagnosing prostate cancer bone metastasis and grading. Patients with Gleason scores>8, higher PSA values after treatment, and shorter times to reach the lowest PSA value had poorer responses to combined androgen blockade treatment.