Network meta-analysis of the efficacy and adverse effects of several treatments for advanced/metastatic prostate cancer

Efficacy and safety of olaparib combined with abiraterone in patients with metastatic castration-resistant prostate cancer: a systematic review and meta-analysis of randomized controlled trials

Background

Olaparib has been proven for the treatment of metastatic castration-resistant prostate cancer (mCRPC). This meta-analysis aims to comprehensively evaluate the efficacy and safety of the combination of olaparib and abiraterone in patients with mCRPC.

Methods

The literature in PubMed, Embase, and Cochrane Library up until April 27, 2023, was systematically searched. In the studies included in this meta-analysis, olaparib combined with abiraterone was compared with abiraterone combined with placebo.

Results

Two randomized controlled trials involving a total of 938 patients were included. Analysis indicated that olaparib combined with abiraterone significantly prolonged radiographic progression-free survival (rPFS: relative risk [RR] 0.66, 95% confidence interval [CI] 0.55-0.79), time to secondary progression or death (PFS2: hazard ratio [HR] 0.72, 95% CI 0.56-0.93), time to first subsequent therapy or death (TFST: HR 0.75, 95% CI 0.63-0.89), time to second subsequent therapy or death (TSST: HR 0.73, 95% CI 0.58-0.93), and confirmed prostate-specific antigen (PSA) response (RR 1.14, 95% CI 1.05-1.24). However, no statistically significant differences were found in the overall survival (OS: HR 0.87 95% CI 0.70-1.09), objective response rate (ORR: RR 0.97, 95% CI 0.70-1.33), and incidence of total adverse events (RR 1.07, 95% CI 0.94-1.22). A notable detail that the combination of olaparib and abiraterone was associated with an increased incidence of high-grade anemia (RR 7.47, 95% CI 1.36-40.88).

Conclusion

Olaparib combined with abiraterone is effective for patients with mCRPC. However, combination therapy has treatment-related adverse events compared with monotherapy, and this could be improved in future treatment management.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023432287.

177Lu-PSMA Radioligand Therapy Is Favorable as Third-Line Treatment of Patients with Metastatic Castration-Resistant Prostate Cancer. A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

In this systematic review and network meta-analysis (NMA), we aimed to assess the benefits and harms of third-line (L3) treatments in randomized controlled trials (RCTs) of patients with metastatic castration-resistant prostate cancer (mCRPC). Two reviewers searched for publications from 1 January 2006 to 30 June 2021. The review analyzed seven RCTs that included 3958 patients and eight treatments. Treatment with prostate-specific membrane antigen (PSMA)-based radioligand therapy (PRLT) resulted in a 1.3-times-higher rate of median PSA decline ≥50% than treatment with abiraterone, enzalutamide, mitoxantrone, or cabazitaxel (p = 0.00001). The likelihood was 97.6% for PRLT to bring about the best PSA response, out of the examined treatments. PRLT resulted in a 1.1-times-higher six-month rate of median radiographic progression-free survival. Treatment with PRLT in the VISION trial resulted in 1.05-times-higher twelve-month median overall survival than L3 treatment with cabazitaxel in other RCTs. PRLT more often resulted in severe thrombocytopenia and less often in severe leukopenia than did cabazitaxel. In conclusion, for patients with mCRPC, L3 treatment with PRLT is highly effective and safe.

Different therapeutic regimens in the treatment of metastatic prostate cancer by performing a Bayesian network meta-analysis

BACKGROUND

Although androgen deprivation therapy with or without chemotherapy are currently the mainstay of therapy for metastatic prostate cancer, accumulating data suggested the survival benefits from definitive local therapy such as radical prostatectomy or radiation therapy. Hence, this network meta-analysis was aimed to provide a hierarchy of different therapeutic regimens for mPCa.

METHODS

Relevant studies were retrieved comprehensively by searching the online databases of PubMed, EMBASE and Web of Science, published before July 1st, 2018. With the help of R-3.4.0 software and "gemtc-0.8.2" package, network meta-analysis was performed by random-effect model within a Bayesian framework. Hazard ratios and corresponding 95% credible intervals were calculated by Markov chain Monte Carlo methods. The surface under the cumulative ranking curve was also incorporated to rank the corresponding therapeutic regimens.

RESULTS

A total of 55,363 cases from 17 studies were ultimately involved in this study. Ten different therapeutic regimens and three clinical endpoints were finally assessed. As illustrated by our results, local therapy (such as radical prostatectomy or radiation therapy) could provide a relatively more favorable survival rate than systematic therapies (no local therapy, androgen deprivation therapy or androgen deprivation therapy + chemotherapy). Meanwhile, in the comparison of radiation therapy, brachytherapy and intensity modulated radiation therapy were among the best two therapies. Furthermore, radical prostatectomy had a relatively lower cancer specific mortality or all-cause mortality than brachytherapy or intensity modulated radiation therapy, in the comparison of local therapy, whereas brachytherapy showed a relatively longer overall survival than radical prostatectomy.

CONCLUSIONS

Our results indicated that local therapy was better than no local therapy. In a comprehensive comparison of three clinical endpoints (overall survival, cancer specific mortality or all-cause mortality), radical prostatectomy had a relatively lower cancer specific mortality or all-cause mortality than radiation therapy, whereas brachytherapy was superior to radical prostatectomy for overall survival.

Anemia is associated with poor outcomes of metastatic castration-resistant prostate cancer, a systematic review and meta-analysis

Androgen deprivation therapy (ADT) was an important management for metastatic prostate cancer. However, patients would finally progress to the metastatic castration-resistant prostate cancer (mCRPC) and lose sensitivity to ADT. In addition to lower testosterone level, ADT could cause anemia, which might impair the chemotherapy efficiency and worsen the outcomes of cancer patients. However, inconsistent results were found between anemia and mCRPC prognosis. Our study was the first systematic review to evaluate the influence of anemia in mCRPC prognosis. Thirteen studies with 6,484 samples were involved in this meta-analysis. We found anemia would worsen the Overall survival (OS) of mCRPC patients in both prognostic designed studies (HR = 1.55, 95% CI = 1.24-1.94) and retrospective designed studies (HR = 1.82, 95% CI = 1.52-2.18). Prognostic analyses also demonstrated that anemia associated with poor Progression free survival (PFS) (HR = 1.47, 95% CI = 1.22-1.75). In conclusion, we found that anemia was significantly associated with poor OS and PFS of mCRPC patients. Larger RCTs are needed for future study, especially for the evaluation of treatment value for anti-anemia in mCRPC.