It’s always reassuring to receive affirmation, especially when offering a leading edge medical program to prostate cancer patients. Such was the case for us at the Sperling Prostate Center with the December, 2015 publication of a UCLA Medical Center study on the value-added of multiparametric MRI during Active Surveillance (AS). The authoritative Journal of Urology published an article by Felker et al.[i] on how well serial mpMRI during AS could predict that a patient’s prostate cancer had started to progress. (Progression means become more aggressive; for example, change from Gleason 3+3 to Gleason 3+4.) The idea that imaging is so fine-tuned that it can pick up potentially dangerous tumor changes would have been unthinkable 20 years ago, but this paper shows the merits of MRI results when coupled with other factors.
The retrospective study involved 49 prostate cancer patients with Gleason 3+3 PCa who had baseline MRI scans at the time of biopsy. Between January 2011 and May 2015, each man was monitored by a second MRI at least 6 months from biopsy (mean interval was 28.3 months) followed by targeted biopsy. Tissue changes that result from tumor growth or progression can be seen on mpMRI, especially when interpreted by an experience radiological reader. The research team recorded imaging results that could indicate progression to tumor grade > 3+4:
- Increase in the suspicion score of the index lesion
- Greater volume of the index lesions
- Decrease in the index lesion apparent diffusion coefficient values (ADC) from diffusion weighted MRI.
A total of 19 men (39%) were found to have biopsy-proven progression. There was a strong predictive correlation between their having a baseline biopsy tumor core length >3mm or a PSA density (PSAD) > 0.15 at follow-up biopsy. However, adding the MRI results improved the predictive accuracy of finding that the Gleason 3+3 cancer had been upgraded to Gleason 4+3.
At our center, we strongly recommend that a baseline mpMRI be obtained at the beginning of an AS management strategy. Furthermore, monitoring can be well served by a combination of regular PSA and PSAD tests at intervals suggested by the patient’s doctor, along with mpMRI if the blood test values change. A major advantage of adding the imaging is the information it offers to rule a targeted biopsy in or out at each imaging interval.
We strive for excellence, and we want to offer the most valuable clinical information to support AS. As more men are diagnosed with PCa at early stages, they are choosing AS. The best way to insure the safety of that strategy is to combine simple blood tests with our state-of-the-art imaging – an immeasurable value, to be sure.
[i] Felker ER, Wu J, Natarajan S, Margolis DJ et al. Serial MRI in Active Surveillance of Prostate Cancer: Incremental Value. J Urol. 2015 Dec 7. pii: S0022-5347(15)05347-1. doi: 10.1016/j.juro.2015.11.055. [Epub ahead of print]