Does enzalutamide related PSMA upregulation affect outcomes of lutetium-177 PSMA radioligand therapy?

BACKGROUND: Enzalutamide is an antiandrogen drug used prior to lutetium-177 prostate specific membrane antigen (Lu-PSMA) radioligand therapy and has shown promising results for upregulating the PSMA expression on prostate cancer cells. In this study, we aim to compare prostate specific antigen (PSA) level changes in prostate cancer patients who received enzalutamide to those who did not. METHODS: Prostate cancer patients who underwent Lu-PSMA between 2021 and 2023 were retrospectively included. Patients were grouped based on prior enzalutamide therapy: those who received enzalutamide (EZ+) for at least 14 days and those who did not (EZ-). PSA changes and F-18 DCFPyL SUV (Standardized Uptake Values) were compared. RESULTS: Thirty-seven patients were included, 18 EZ+ and 19 EZ-. The median age, Gleason score, and prior chemo/hormonal therapies were similar for EZ+ and EZ-, except for radium-223. Eleven patients (61%) in EZ+ and 13 patients (68%) in EZ- showed a decrease in PSA after the first cycle (p = 0.64). Four patients (22%) in EZ+ and seven patients (37%) in EZ- had more than 50% decrease in PSA after the first cycle (p = 0.33). The average percent decline at the end of the treatment was 23.3% in EZ+ and 50.4% in EZ- (p = 0.4). There was no difference in terms of lesion with highest SUVmax, mean SUV, total tumor volume or activity on pre-therapy PSMA imaging. CONCLUSION: Enzalutamide treatment prior to Lu-PSMA does not improve patient outcomes when applied remotely. Larger studies evaluating the combination therapies and the timing of enzalutamide are needed to assess its correlation with Lu-PSMA outcomes.

Catastrophic Events of Cardiac Sarcoidosis: A Case Report.

Cardiac sarcoidosis (CS) can be silent in most patients with extrapulmonary sarcoidosis. Atrioventricular (AV) block is the most common clinical presentation, but it can also present as fatal ventricular arrhythmias and sudden cardiac death. Endomyocardial biopsy is the gold standard; however, it is not sensitive since CS can involve the myocardium in a patchy distribution. Our case depicts a female who presented with syncope; however, her hospital course was complicated by multiple cardiac arrests. Her initial laboratory tests, including an autoimmune workup, were unremarkable. Cardiac magnetic resonance and fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging revealed intramyocardial delayed enhancement of the basal anteroseptal (non-ischemic distribution) and patchy foci of increased uptake in the anteroseptal and inferior myocardial region, respectively. The patient was started on intravenous methylprednisolone, and her condition slowly improved. Post-discharge, the patient followed in the outpatient clinic with a repeat FDG-PET scan revealing resolution of myocardial FDG uptake. She also underwent bronchoscopy with lymph node biopsy showing granulomas and endobronchial biopsy confirming pulmonary sarcoidosis.

Col11a1 Regulates Bone Microarchitecture during Embryonic Development.

Collagen XI alpha 1 (Col11a1) is an extracellular matrix molecule required for embryonic development with a role in both nucleating the formation of fibrils and regulating the diameter of heterotypic fibrils during collagen fibrillar assembly. Although found in many different tissues throughout the vertebrate body, Col11a1 plays an essential role in endochondral ossification. To further understand the function of Col11a1 in the process of bone formation, we compared skeletal mineralization in wild-type (WT) mice and Col11a1-deficient mice using X-ray microtomography (micro-CT) and histology. Changes in trabecular bone microstructure were observed and are presented here. Additionally, changes to the periosteal bone collar of developing long bones were observed and resulted in an increase in thickness in the case of Col11a1-deficient mice compared to WT littermates. Vertebral bodies were incompletely formed in the absence of Col11a1. The data demonstrate that Col11a1 depletion results in alteration to newly-formed bone and is consistent with a role for Col11a1 in mineralization. These findings indicate that expression of Col11a1 in the growth plate and perichondrium is essential for trabecular bone and bone collar formation during endochondral ossification. The observed changes to mineralized tissues further define the function of Col11a1.