A recent article (in German in Der Urologe) has discussed the early use of PSMA-radio-guided surgery (PSMA-RGS) for targeted resection of localized prostate cancer recurrence.
This article by Rauscher et al. introduces the concept of being able to better identify and then surgically remove one (or perhaps occasionally two) small areas of soft tissue or lymph node recurrent prostate cancer. (And by “better identify” we are implying better than with techniques like [11C]choline PET/CT scanning.)
The base premise for the application of this technique is that tumor recurrence must be initially identifiable through a positive 68Ga-HBED-CC PSMA positron emission tomography (PET) scan, thus optimizing the potential for appropriate patient selection.
Following initial patient identification, patients have been given either an 111In-PSMA or a 99mTc-PSMA SPECT/CT examination to verify radiotracer uptake in tumor lesions.
In a initial study, 111In-PSMA SPECT/CT could detect about half of the 68Ga-HBED-CC PSMA PET-positive lesions, while nearly all PET-positive lesions could be detected using PSMA-RGS and also five additional lesions compared to 68Ga-HBED-CC-PSMA PET.
Follow-up data from 55 patients post-surgery showed the following:
- A PSA reduction of > 50 percent in 44/55 patients (80 percent)
- A PSA reduction of > 90 percent in 29/55 patients (53 percent)
- A drop in PSA level to < 0.2 ng/ml in 34/55 patients (62 percent)
- Further prostate cancer-specific treatment was required in 15/55 patients (27 percent) at an average (median) follow-up of 110 days after PRMA-RGS (range, 48 to 454 days)
- No further prostate cancer-specific treatment was required in 40/55 patients (73 percent) at an average (median) follow-up of 195 days after PRMA-RGS (range, 43 to 591 days)
- Surgery-related complications were observed 33 percent of patients (but most are said to have been “minor”)
Based on these early date, the authors conclude that
PSMA-RGS seems to be of high value in patients with localized prostate cancer recurrence with exact localization and resection of metastatic tissue. However, patient selection based on 68Ga-PSMA PET imaging and clinical parameters is crucial to obtain satisfactory oncological results.
The implications of this paper are also discussed in a “Beyond the Abstract” commentary on the UroToday web site.
What we are seeing here is a further example of the increasingly sophisticated options that are coming available for carefully selected patients who may show signs of recurrence associated with just one or perhaps two clearly identifiable areas of disease recurrence. The long-term effectiveness of such treatments will need to be tracked with care (and in larger numbers of patients).
Filed under: Living with Prostate Cancer, Management, Treatment | Tagged: identification, PSMA, radio-guidance, recurrence, surgery, tumor |
THE "NEW" PROSTATE CANCER INFOLINK 
With a lucky few exceptions, I imagine any of us on AS must second-guess and worry at least some of the time (and, of course, not just us on AS, but also those who have had treatment and sweat the PSA tests even more, etc.).
Personally, I find the progress being made on the “risk” side of the equation immensely helpful in that regard. So good luck to advanced sufferers: I hope the progress is in time for you and so for me, if I am to join you.