PET tracer detects early progression of prostate cancer in patients receiving bipolar androgen therapy: Study
Maryland: A recent study has found that PET imaging can identify whether or not patients respond to an investigational therapy for prostate cancer.
According to the study, published in The Journal of Nuclear Medicine, new radiotracer-avid lesions on 18F-DCFPyL PET/CT can indicate early progression in men with metastatic castration-resistant prostate cancer (mCRPC) undergoing bipolar androgen therapy (BAT).
Androgen (testosterone) deprivation therapy is the standard treatment approach for men with prostate cancer, but often the treatment stops working because prostate cancer cells adapt to the lower levels. Paradoxically, however, research has also shown that high concentrations of androgens are able to suppress tumor growth.
Bipolar androgen therapy is an emerging treatment for metastatic castration-resistant prostate cancer. 18F-DCFPyL is a small-molecule PET radiotracer targeting prostate-specific membrane antigen (PSMA). Mark C. Markowski, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland, and colleagues analyzed the utility of 18F-DCFPyL PET/CT in determining clinical response to BAT.
The study included six men with mCRPC receiving BAT who were imaged with 18F-DCFPyL PET/CT at baseline and after 3 mo of treatment. Progression by PSMA-targeted PET/CT was defined as the appearance of any new 18F-DCFPyL–avid lesion.
The study yielded the following findings:
- 50% of patients had progression on 18F-DCFPyL PET/CT. All 3 had stable disease or better on contemporaneous conventional imaging.
- Radiographic progression on CT or bone scanning was observed within 3 months of progression on 18F-DCFPyL PET/CT.
- For the 3 patients who did not have progression on 18F-DCFPyL PET/CT, radiographic progression was not observed for at least 6 months.
The researchers concluded, "new radiotracer-avid lesions on 18F-DCFPyL PET/CT in men with mCRPC undergoing BAT can indicate early progression."
The study titled, "Detection of Early Progression with 18F-DCFPyL PET/CT in Men with Metastatic Castration-Resistant Prostate Cancer Receiving Bipolar Androgen Therapy," is published in The Journal of Nuclear Medicine.