Safety and efficacy of ¹⁷⁷Lu-PSMA-I&T Radioligand Therapy in Octogenarians with metastatic castration-resistant prostate cancer: Report on eighty patients over age eighty

Ziel/Aim ¹⁷⁷Lu-PSMA radioligand (RLT) therapy is a new treatment option for metastatic castration-resistant prostate cancer (mCRPC). Its low toxicity profile favors the use in elderly patients. Purpose of this study was to evaluate the safety and efficacy of ¹⁷⁷Lu-PSMA-RLT in mCRPC patients≥80 years of age.

Methodik/Methods Eighty mCRPC patients with≥80 years of age underwent ¹⁷⁷Lu-PSMA-I&T RLT and were retrospectively selected from our database. Patients have previously been treated by androgen receptor-directed therapy with Abiraterone or Enzalutamide, received taxane-based chemotherapy or were chemotherapy-ineligible. All patients showed high PSMA-ligand uptake at baseline PSMA-PET. Toxicity data were acquired until 6 months after last treatment cycle. Best PSA-response, clinical progression-free survival (cPFS) and overall survival (OS) were calculated.

Ergebnisse/Results A total number of 324 cycles (median 4 cycles, range: 1–12) were applied. 49 (61.3%) patients were chemotherapy-naïve (CTx-naïve) and 16 (20%) patients had visceral metastases. A PSA decline of 50% was achieved in 37 (46.3%) patients. CTx-naïve patients showed higher 50% PSA response rates compared to CTx-pretreated patients (51.0% vs. 38.7%). Overall, median cPFS and OS were 8.7 and 16.1 mo, respectively. Median cPFS and OS of CTx-naïve patients were significantly longer compared to CTx-pretreated patients (10.5 vs. 6.5 mo and 20.7 vs. 11.8 mo, respectively, p<0.05). Lower hemoglobin level and higher LDH level at baseline were independent predictors of poorer cPFS and OS. Treatment-emergent grade 3 toxicities were anemia in 4 (5%), thrombocytopenia in 3 (3.8%) and renal impairment in 4 (5%) patients.

Schlussfolgerungen/Conclusions ¹⁷⁷Lu-PSMA-I&T RLT in elderly mCRPC patients≥80 years is safe and effective, comparable to previously published data of non-age selected cohorts with a low rate of high grade toxicities. Chemotherapy-naïve patients constituting the majority of this cohort showed a better and longer response to therapy than taxane-pretreated patients.

Publication History

Article published online:
30 March 2023