Researchers have found in a new research that PET CT better than contrast-enhanced CT as survival predictor in metastatic breast cancer patients. 2-[18F]FDG-PET/CT, when used to monitor metastatic breast cancer, appears to be a stronger predictor of progression-free and disease-specific survival than conventional contrast-enhanced CT (CE-CT), says an article published in Scientific Reports.
Metastatic breast cancer (MBC) is an incurable illness; however, increasingly effective therapies have enhanced survival and turned MBC into a chronic condition. Monitoring the effect of therapy is critical to ensuring that it continues successfully or, if not, allowing for a prompt change in treatment. Marianne Vogsen and colleagues conducted this study to evaluate CE-CT with 2-[18F]FDG-PET/CT for reaction monitoring in metastatic breast cancer.

The main goal of this study was to compare responders and non-responders to CE-CT and 2-[18F]FDG-PET/CT results in order to predict progression-free and disease-specific survival. Assessing agreement between the answer classifications for the two modalities was the secondary goal. By simultaneously using CE-CT and 2-[18F]FDG-PET/CT to track treatment response in women with MBC, participants may act as their own controls. Response classification was done using the RECIST 1.1 standard for solid tumor response assessment and the PERCIST PET response criteria. At the initial follow-up scan, the treatment response was divided into responders (partial and complete responses) and non-responders (stable and progressing illness) for the purpose of predicting progression-free and disease-specific survival. The duration from the baseline to illness progression or death from any cause was referred to as progression-free survival.
The key findings of this study were:
1. The period from the baseline till a death due to breast cancer specifically was referred to as disease-specific survival.
2. For all response categories and responders vs non-responders, agreement between response classification for both modalities was examined.
3. Tumor response was recorded by 2-[18F]FDG-PET/CT more frequently than by CE-CT at the initial follow-up, with only fair agreement on response classification between the two modalities (weighted Kappa 0.28).
4. Comparing responders and non-responders by CE-CT, the two-year progression-free survival was 54.2% vs. 46.0%, as opposed to 59.1% vs. 14.3% by 2-[18F]FDG-PET/CT.
5. Accordingly, 2-year disease-specific survival was 84.6% vs. 61.9% for 2-[18F]FDG-PET/CT and 83.3% vs. 77.8% for CE-CT.
6. While no connection was detected for tumor response on CE-CT, tumor response on 2-[18F]FDG-PET/CT was substantially linked with progression-free survival (HR: 3.49, P 0.001) and disease-specific survival (HR: 2.35, P = 0.008).
When used to track the effects of therapy in women with metastatic breast cancer, 2-[18F]FDG-PET/CT proved to be a more accurate predictor of progression-free and disease-specific survival than CE-CT. Moreover, we discovered a poor agreement between CE-CT and 2-[18F]FDG-PET/CT when it came to response categorization. Further research contrasting the two modalities for patient-related advantages including overall survival and quality of life is necessary.
Reference:
Vogsen, M., Naghavi-Behzad, M., Harbo, F. G., Jakobsen, N. M., Gerke, O., Asmussen, J. T., Nissen, H. J., Dahlsgaard-Wallenius, S. E., Braad, P.-E., Jensen, J. D., Ewertz, M., & Hildebrandt, M. G. (2023). 2-[18F]FDG-PET/CT is a better predictor of survival than conventional CT: a prospective study of response monitoring in metastatic breast cancer. In Scientific Reports (Vol. 13, Issue 1). Springer Science and Business Media LLC. https://doi.org/10.1038/s41598-023-32727-w