Sarcopenia and survival in metastatic castration-resistant prostate cancer patients treated with novel hormonal therapy (Abiraterone, Enzalutamide)

Aim: Under hormonal therapy (HT), most prostate cancer patients progress into metastatic castration-resistant prostate cancer (MKDPK). The most important among HT procedure is androgen deprivation therapy. ADT (androgen deprivation therapy) includes surgical castration and LHRH agonists/antagonists. This patient group may benefit from HT before, after, or in addition to chemotherapy. Therefore, mCRPC patients have various therapy options. Sarcopenia has an impact on mCRPC patients' survival considered with HT remains unknown, therefore CT and PSMA-PET/CT imaging is used for follow-up. Our study observed pre- and post-treatment SMI values in mCRPC patients using abiraterone or enzalutamide as a new-generation hormonal agent (YNHA) for androgen (testosterone) suppression to investigate sarcopenia in this population and their effect on survival. Materials and Methods: We included metastatic castration-resistant prostate cancer patients who applied to our Medical Oncology outpatient clinic between 2010 and 2023. A standard protocol was used to obtain abdominal and pelvic CT images. Using a monophasic 80-100 ml bolus of 2 mL/s, 70th second portal venous phase images were obtained with iohexol 300 (Omnipaque 300) contrast. CT settings are 5 mm slice thickness, 120 kVp, 290 mA. VITREA calculated the volume in cm2 of the psoas, rectus abdominus, paraspinal, transversus abdominis, internal, and external obliques in a single L3 section. Results: Patients who had abiraterone or enzalutamide therapy for mCRPC and developed sarcopenia had a median OS of 24.8 months (19.1-30.4). Sarcopenia identified throughout treatment reduced the risk of mortality by 39% (HR = 0.61; 95% CI: 0.380-0.978; p = 0.04) in multivariate survival analysis. There was no survival benefit from visceral metastasis (HR = 1.682; 95% CI: 0.927-3.054; p = 0.087). Conclusion: The study findings indicate that the existence of sarcopenia before therapy did not demonstrate any significant impact on survival outcomes. It has been established that there is a general survival benefit in patients with sarcopenia who undergo treatment. Hence, it was hypothesized that the existence of sarcopenia during the course of therapy could serve as a potential marker for treatment efficacy and confer a survival benefit.