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. 2023 Jul 11;308(1):e222148. doi: 10.1148/radiol.222148

Figure 4:

Patient examples of disagreement between visual Response Evaluation Criteria in Prostate-specific Membrane Antigen (PSMA) PET/CT (RECIP) and quantitative RECIP. (A) Fluorine 18 rhPSMA-7.3 PET maximum intensity projection images in a 77-year-old man with metastatic castration-resistant prostate cancer previously treated with docetaxel, abiraterone, and enzalutamide. The serum prostate-specific antigen level at baseline was 2547 ng/mL and declined after two cycles of lutetium 177 (177Lu) PSMA to 1866 ng/mL (27% decrease). All readers detected at least one new lesion at the interim PET examination. Three of five readers classified disease in this patient as nonprogression in PSMA-positive total tumor volume (TTV) (majority rule), which resulted in non–progressive disease (PD) according to visual RECIP. Quantitative analysis of TTV showed an increase from 1978 mL at baseline to 2567 mL at interim PET (30% increase; progression), and it was classified as PD according to quantitative RECIP. The tumor lesions were annotated using qPSMA software, version 1.0, and are highlighted in red on the maximum intensity projection images. A total of four cycles of 177Lu-PSMA were applied. Overall survival was 13.1 months. (B) Gallium 68 PSMA-11 PET maximum intensity projection images in a 69-year-old man with metastatic castration-resistant prostate cancer previously treated with abiraterone and enzalutamide and unfit for chemotherapy. The serum prostate-specific antigen level at baseline was 89 ng/mL and increased after two cycles of 177Lu-PSMA to 138 ng/mL (55% increase). All readers detected at least one new lesion at the interim PSMA PET/CT examination. Four of five readers classified this patient as having progression in TTV (majority rule), which resulted in PD according to visual RECIP. Quantitative analysis of TTV showed an increase from 351 mL at baseline to 373 mL on interim PET (6% increase; nonprogression), which resulted in non-PD according to quantitative RECIP. The tumor lesions are highlighted in red on the maximum intensity projection images. The treatment with 177Lu-PSMA was discontinued after two cycles. The overall survival in this patient was 20.5 months.

Patient examples of disagreement between visual Response Evaluation Criteria in Prostate-specific Membrane Antigen (PSMA) PET/CT (RECIP) and quantitative RECIP. (A) Fluorine 18 rhPSMA-7.3 PET maximum intensity projection images in a 77-year-old man with metastatic castration-resistant prostate cancer previously treated with docetaxel, abiraterone, and enzalutamide. The serum prostate-specific antigen level at baseline was 2547 ng/mL and declined after two cycles of lutetium 177 (177Lu) PSMA to 1866 ng/mL (27% decrease). All readers detected at least one new lesion at the interim PET examination. Three of five readers classified disease in this patient as nonprogression in PSMA-positive total tumor volume (TTV) (majority rule), which resulted in non–progressive disease (PD) according to visual RECIP. Quantitative analysis of TTV showed an increase from 1978 mL at baseline to 2567 mL at interim PET (30% increase; progression), and it was classified as PD according to quantitative RECIP. The tumor lesions were annotated using qPSMA software, version 1.0, and are highlighted in red on the maximum intensity projection images. A total of four cycles of 177Lu-PSMA were applied. Overall survival was 13.1 months. (B) Gallium 68 PSMA-11 PET maximum intensity projection images in a 69-year-old man with metastatic castration-resistant prostate cancer previously treated with abiraterone and enzalutamide and unfit for chemotherapy. The serum prostate-specific antigen level at baseline was 89 ng/mL and increased after two cycles of 177Lu-PSMA to 138 ng/mL (55% increase). All readers detected at least one new lesion at the interim PSMA PET/CT examination. Four of five readers classified this patient as having progression in TTV (majority rule), which resulted in PD according to visual RECIP. Quantitative analysis of TTV showed an increase from 351 mL at baseline to 373 mL on interim PET (6% increase; nonprogression), which resulted in non-PD according to quantitative RECIP. The tumor lesions are highlighted in red on the maximum intensity projection images. The treatment with 177Lu-PSMA was discontinued after two cycles. The overall survival in this patient was 20.5 months.