The Prognostic Role of ⁶⁸GA-PSMA-PET/CT in Metastatic Hormone-Sensitive Prostate Cancer: A Preliminary Analysis

In metastatic hormone-sensitive prostate cancer (mHSPC), to evaluate therapy response is currently used conventional imaging and PSA levels. Positron emission tomography with ⁶⁸Gallium Prostate-specific membrane antigen (⁶⁸Ga-PSMA-PET/CT) could be useful, although it is not recommended by international guidelines. Its prognostic utility has been already investigated in several works in the castration-resistant setting, but no sufficient efforts have been made to better define it in mHSPC.

Retrospective monocentric study to preliminary explore the value of ⁶⁸Ga-PSMA-PET/CT in this setting. We enrolled metastatic patients at the baseline ⁶⁸Ga-PSMA-PET/CT, treated with androgen deprivation therapy plus docetaxel or androgen receptor signaling inhibitors (ARSI) or both as first-line.

The survival analysis indicated that a Major SUVmax exceeding the cut-off (P = .037) and a SUVmean above the cut-off (P = .025) were linked to improved progression-free survival (PFS) as compared to values ≤ cut-off. While several parameters were associated with undetectable PSA levels at any point after the initiation of first-line therapy, only low-volume disease (HR 7.64, P .002), MTV ≤ cut-off 3-months PSA (HR 5.36, P = .012) and SUVmean ≤ cut-off 3-months PSA (HR 38.6, P < .001) were associated with a higher probability of reaching an undetectable value of PSA in the multivariate analysis.

retrospective nature, short follow-up time and lack of comparison with conventional imaging.

Lower values of ⁶⁸Ga-PSMA-PET/CT derived-parameters at baseline are negative prognostic factor, in view of the correlation with lower PFS. This study could help oncologists in the management of mHSPC patients, although further investigations are needed to better understand the prognostic and predictive ⁶⁸Ga-PSMA-PET/CT role in this setting.