Evaluation of whole-body tumor burden with 68Ga-PSMA PET/CT in the biochemical recurrence of prostate cancer

Metabolic Tumour Volume from PSMA PET/CT Scans of Prostate Cancer Patients during Chemotherapy—Do Different Software Solutions Deliver Comparable Results?

“…We were able to show significant correlations between serum PSA values and PSMA-TV as well as TL-PSMA at baseline and follow-up in accordance to previous studies [10,11,14,24]. These earlier publications showed correlations between relative ∆PSMA-TV and ∆PSMA-TL with relative changes in serum PSA-levels in patients undergoing androgen deprivation, radiotherapy and radioligand therapy [10,12,24].…”

“…Going one step back, it is also unknown whether choosing different software solutions for determining metabolic tumour volume influences outcome. For calculation of PSMA-TV and TL-PSMA, different authors used different software (Syngo.via, METAVOL, LifeX or custom-made programs) and currently it is unclear whether their results are seamlessly comparable [11][12][13][14]. To address these issues, we analysed pre-and post-therapeutic 68 Ga-PSMA PET/CT scans of PCa patients receiving chemotherapy -first, with Syngo.via and afterwards with the FIJI algorithm.…”

“…Further research on this topic is needed, as an in-depth analysis of the prognostic impact of PERCIST on the overall survival is limited due to our small sample size and was not the primary scope of our study. Brito et al for example published an approach where they suggested using TL-PSMA for separating PCa patients into two groups with a high or low tumour burden instead of only counting the number of lesions [11].…”

“…However, a variety of software algorithms delivers metabolic tumour volume markers such as PSMA-TV and TL-PSMA. Accordingly, studies examining metabolic tumour volume derived from PSMA PET/CT used different software tools [11][12][13][14].…”

Determination of whole-body tumour burden on [68Ga]PSMA-11 PET/CT for response assessment of [177Lu]PSMA-617 radioligand therapy: a retrospective analysis of serum PSA level and imaging derived parameters before and after two cycles of therapy

“…Another possibility of response assessment using FDG is the determination of so-called total lesion glycolysis, e. g. as a marker of disease activity in lymphoma [10]. This approach has been transferred to PSMA PET [11][12][13] and was propagated as a good marker of whole-body tumour burden. On [ 68 Ga]PSMA-11 PET-scans in oligometastatic patients, a good correlation has been observed between serum PSA level and total volume PSMA (PSMA-TV) -which represents the "metabolic" tumor volume-as well as between PSA and so-called total lesion PSMA (TL-PSMA), that also takes the mean standardized uptake value (SUV) of the aforementioned PSMA-TV into account [11,12].…”