PSMA PET total tumor volume predicts outcome of patients with advanced prostate cancer receiving [177Lu]Lu-PSMA-617 radioligand therapy in a bicentric analysis

• DOI: 10.1007/s00259-020-05040-1
• Publication Date: 2020-09-24T04:02:23Z
• Authors: Robert Seifert; Katharina Kessel; Katrin Schlack; Manuel Weber; Ken Herrmann; Maximilian Spanke; Wolfgang P. Fendler; Boris Hadaschik; Jens Kleesiek; Michael Schäfers; Matthias Weckesser; Martin Boegemann; Kambiz Rahbar
• Keywords: Male; Dipeptides; Prostate-Specific Antigen; 3. Good health; Tumor Burden; Heterocyclic Compounds, 1-Ring [MeSH] ; Oncology – Genitourinary ; Humans [MeSH] ; Prostate-Specific Antigen [MeSH] ; Treatment Outcome [MeSH] ; Positron Emission Tomography Computed Tomography [MeSH] ; Retrospective Studies [MeSH] ; Lu-PSMA ; Prostatic Neoplasms, Castration-Resistant [MeSH] ; PSMA ; Original Article ; PET-CT ; Male [MeSH] ; Total tumor volume ; Dipeptides/therapeutic use [MeSH] ; Tumor Burden [MeSH] ; mCRPC; Heterocyclic Compounds, 1-Ring; Prostatic Neoplasms, Castration-Resistant; 03 medical and health sciences; Treatment Outcome; 0302 clinical medicine; Positron Emission Tomography Computed Tomography; Humans; Original Article; Retrospective Studies

Abstract Introduction [177Lu]Lu-PSMA-617 (Lu-PSMA) radioligand therapy is an emerging treatment option for patients with end-stage prostate cancer. However, response to Lu-PSMA therapy is only achieved in approximately half of patients. It is clinically important to identify patients at risk of poor outcome. Therefore, the aim of this study was to evaluate pretherapeutic PSMA PET derived total tumor volume and related metrics as prognosticators of overall survival in patients receiving Lu-PSMA therapy.

Methods A total number of 110 patients form the Departments of Nuclear Medicine Münster and Essen were included in this retrospective analysis. Baseline PSMA PET-CT was available for all patients. Employing a previously published approach, all tumor lesions were semi-automatically delineated in PSMA PET-CT acquisitions. Total lesion number, total tumor volume (PSMA-TV), total lesion uptake (PSMA-TLU = PSMA-TV * SUVmean), and total lesion quotient (PSMA-TLQ = PSMA-TV / SUVmean) were quantified for each patient. Log2 transformation was used for regressions.

Results Lesion number, PSMA-TV, and PSMA-TLQ were prognosticators of overall survival (HR = 1.255, p = 0.009; HR = 1.299, p = 0.005; HR = 1.326, p = 0.002). In a stepwise backward Cox regression including lesion number, PSMA-TV, PSA, LDH, and PSMA-TLQ, only the latter two remained independent and statistically significant negative prognosticators of overall survival (HR = 1.632, p = 0.011; HR = 1.239, p = 0.024). PSMA-TLQ and LDH were significant negative prognosticators in multivariate Cox regression in contrast to PSA value.

Conclusion PSMA-TV was a statistically significant negative prognosticator of overall survival in patients receiving Lu-PSMA therapy. PSMA-TLQ was an independent and superior prognosticator of overall survival compared with PSMA-TV.