PT  - JOURNAL ARTICLE
AU  - Barbato, Francesco
AU  - Fendler, Wolfgang P.
AU  - Rauscher, Isabel
AU  - Herrmann, Ken
AU  - Wetter, Axel
AU  - Ferdinandus, Justin
AU  - Seifert, Robert
AU  - Nader, Michael
AU  - Rahbar, Kambiz
AU  - Hadaschik, Boris
AU  - Eiber, Matthias
AU  - Gafita, Andrei
AU  - Weber, Manuel
TI  - PSMA PET for the Assessment of Metastatic Hormone-Sensitive Prostate Cancer Volume of Disease
AID  - 10.2967/jnumed.121.262120
DP  - 2021 Dec 01
TA  - Journal of Nuclear Medicine
PG  - 1747--1750
VI  - 62
IP  - 12
4099  - http://jnm.snmjournals.org/content/62/12/1747.short
4100  - http://jnm.snmjournals.org/content/62/12/1747.full
SO  - J Nucl Med2021 Dec 01; 62
AB  - Conventional imaging of low-volume disease (LVD) versus high-volume disease (HVD) is associated with survival in metastatic hormone-sensitive prostate cancer (mHSPC) according to the CHAARTED trial (Chemohormonal Therapy in Metastatic Hormone-Sensitive Prostate Cancer) and the STAMPEDE trial (Systemic Therapy for Advanced or Metastatic Prostate Cancer: Evaluation of Drug Efficacy). We propose a compatible quantitative PSMA PET framework for disease volume assessment in mHSPC. Methods: Three PET centers screened their PSMA PET database for mHSPC patients. CT versus PSMA PET stage, lesion number, and classification of LVD versus HVD were determined by 1 masked reader; PSMA-positive tumor volume was quantified semiautomatically. Results: In total, 85 CT-based CHAARTED LVD and 20 CT-based CHAARTED HVD patients were included. A PSMA tumor volume of about 40 cm3 was the optimal cutoff between CT-based CHAARTED LVD (nonunifocal) and HVD (non-M1c) (area under the curve, 0.86). Stratification into PET LVD (unifocal or oligometastatic/disseminated < ∼40 cm3) and PET HVD (oligometastatic/disseminated ≥ ∼40 cm3 or M1c) had 13% misalignment with the CHAARTED criteria. Conclusion: PSMA PET criteria with volume quantification deliver comparable LVD/HVD discrimination with additional subgroups for unifocal, oligometastatic, and disseminated disease, critical for guidance of targeted or multimodal therapy.