MP18-08: The relationship between uptake on PSMA PET imaging and clinical and genomic factors in initial staging for patients with prostate cancer
Friday, May 3, 2024 3:30 PM to 5:30 PM · 2 hr. (US/Central)
302B
Abstract
Information
Full Abstract and Figures
Author Block
Domenique Escobar, Kevin Chang*, Abuzar Moradi Tuchayi, Janet E Cowan, Lufan Wang, Matthew R Cooperberg, Peter R Caroll, Thomas A Hope, San Francisco, CA
Introduction
Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) is an important tool in the diagnosis of prostate cancer. However, little is known about the relationship between the maximum standardized uptake value (SUVmax) of the primary tumor and clinical and genomic factors in patients with prostate cancer, or how to use this value clinically. We aimed to better understand this relationship in a cohort of patients undergoing radical prostatectomy (RP).
Methods
Retrospective review was performed to identify all PSMA PET scans done for initial staging. SUVmax was measured. Demographic, clinical and genomic data were abstracted from the medical record. Sensitivity and specificity of the PSMA PET scans for lymph node positivity at RP were calculated. Relationships between SUVmax and clinical and genomic factors were evaluated graphically and with Chi square and correlation coefficient tests.
Results
591 PSMA PET scans were performed at initial staging. 218 patients underwent RP and were included for analysis. 38 patients had positive pelvic lymph nodes on PSMA PET prior to RP, and 43 patients had positive lymph nodes at RP. The median Decipher score was 0.71 with an IQR of 0.56 – 0.87 and the median SUVmax of the primary tumor on PSMA PET was 13.6 with an IQR of 8.2 – 20.7 for the RP cohort. There was an increase in sensitivity of PSMA PET by SUVmax quartile: sensitivity of 0.25 for SUV quartile 1, 0.30 for SUV quartile 2, 0.50 for SUV quartile 3 and 0.72 for SUV quartile 4 (p>0.05). Specificities were similar across quartiles ranging from 0.87 – 0.93. There was no relationship between the SUVmax and lymph node positivity at RP (p=0.48), final Gleason score at RP (p=0.63), ECE at RP (p=0.27), seminal vesicle invasion at RP (p=0.41) or Decipher score (r=0.14).
Conclusions
The sensitivity of PSMA PET for pelvic lymph node positivity at RP increased with increasing SUVmax of the primary tumor, although not statistically significant in this study. However, there was no relationship between the SUVmax and overall lymph node positivity at RP, various pathologic factors at RP or Decipher score indicating a limitation in the clinical utility of the SUVmax in terms of risk stratification or assessing disease aggressiveness.
Source Of Funding
NIH T32, UCSF Department of Radiology
Author Block
Domenique Escobar, Kevin Chang*, Abuzar Moradi Tuchayi, Janet E Cowan, Lufan Wang, Matthew R Cooperberg, Peter R Caroll, Thomas A Hope, San Francisco, CA
Introduction
Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) is an important tool in the diagnosis of prostate cancer. However, little is known about the relationship between the maximum standardized uptake value (SUVmax) of the primary tumor and clinical and genomic factors in patients with prostate cancer, or how to use this value clinically. We aimed to better understand this relationship in a cohort of patients undergoing radical prostatectomy (RP).
Methods
Retrospective review was performed to identify all PSMA PET scans done for initial staging. SUVmax was measured. Demographic, clinical and genomic data were abstracted from the medical record. Sensitivity and specificity of the PSMA PET scans for lymph node positivity at RP were calculated. Relationships between SUVmax and clinical and genomic factors were evaluated graphically and with Chi square and correlation coefficient tests.
Results
591 PSMA PET scans were performed at initial staging. 218 patients underwent RP and were included for analysis. 38 patients had positive pelvic lymph nodes on PSMA PET prior to RP, and 43 patients had positive lymph nodes at RP. The median Decipher score was 0.71 with an IQR of 0.56 – 0.87 and the median SUVmax of the primary tumor on PSMA PET was 13.6 with an IQR of 8.2 – 20.7 for the RP cohort. There was an increase in sensitivity of PSMA PET by SUVmax quartile: sensitivity of 0.25 for SUV quartile 1, 0.30 for SUV quartile 2, 0.50 for SUV quartile 3 and 0.72 for SUV quartile 4 (p>0.05). Specificities were similar across quartiles ranging from 0.87 – 0.93. There was no relationship between the SUVmax and lymph node positivity at RP (p=0.48), final Gleason score at RP (p=0.63), ECE at RP (p=0.27), seminal vesicle invasion at RP (p=0.41) or Decipher score (r=0.14).
Conclusions
The sensitivity of PSMA PET for pelvic lymph node positivity at RP increased with increasing SUVmax of the primary tumor, although not statistically significant in this study. However, there was no relationship between the SUVmax and overall lymph node positivity at RP, various pathologic factors at RP or Decipher score indicating a limitation in the clinical utility of the SUVmax in terms of risk stratification or assessing disease aggressiveness.
Source Of Funding
NIH T32, UCSF Department of Radiology
Sessions
MP18: Imaging/Uroradiology I
302B