Visualase Focal Laser Ablation

Anyone here have any experience with this therapy? Visualase is a focal laser ablation being used predominately for MIS neurosurgery, but is also FDA approved for use in prostate. The reason I ask is that I am presently in active surveillance after my PC diagnosis this past June. My PSA is now at 5.15 (diagnosed via BX with one G6 lesion less than 1 mm). My PSA has continued to uptick slightly from when diagnosed. My last 4 were (tested every 3 months) 4.99, 3.89, 4.4 and now 5.15.

Given that I only have one small lesion I may be a great candidate for this treatment. I would like to see if any members here have consulted or have had this treatment for their PC.

Thanks in advance for your help.

PC Legacy

Both Dr. Leonard Marks at UCLA and Dr.John Feller in Indian Wells, CA have clinical trials running that you seem to qualify for. They both use MR guidance to ablate the index lesion. The advantages are that it's relatively non-intrusive, and requires only an office visit with no general anesthesia, and SEs are low. The disadvantages, are that there is a high recurrence rate, sometimes requiring multiple procedures, and as treatments increase, so do SEs. It also matters a great deal just where the index lesion is; if it's close to sensitive structures, like the bladder neck, urethral sphincter, neurovascular bundles or rectum, there is a danger of thermal damage.

Focal ablation is kind of a half-way therapy between full gland (radical) therapy and active surveillance. Because of its high recurrence rate, you are essentially on active surveillance for your lifetime after therapy.

To avoid thermal damage associated with HIFU, cryo, laser, and RF, they have come up with some non-thermal techniques. IRE is being studied in clinical trials (Dr. Coleman at MSKCC would have done a few by now.). Focal SBRT will be tried at Cleveland Clinic starting in June. BC and Sunnybrook have trials of focal HDR brachy. BC also has a trial of focal LDR brachy.

PCLegacy said...
I wouldn't think anything that is ablated would grow back. If you know something to the contrary on this I would certainly want to know.

Not quite accurate. First of all, 80% of prostate cancer is multifocal - even the ones that seem to have only one positive core. On pathology, they almost always find microscopic bits of cancer throughout. The "index lesion theory" is that those micromets aren't the source of the cancer's spread, and only the "mother tumor" is responsible. It seems to be partly true at least, but far from proven.

The other difficulty is that even our best MRI imaging techniques are only accurate to about 4 mm. Tumors smaller than that can't be seen. Usually the focal therapist will treat a margin outside of the visible dominant lesion to try to get it all. However, there is no assurance. Tumors just outside of the ring of total ablation get sub-lethal damage. Tumor cells are especially good at surviving sub-lethal damage - they use "heat shock proteins" to protect the vital structures within the cell, and go into cell-cycle arrest while they self repair. It is thought that many of the recurrences arise from those sub-lethal treatment margins. Even when whole glands are treated, around 40% have local failures within 5 years - ablation is not the surest way to kill cancer cells.

With focal ablation, around 10-20% have a local clinical failure (biopsy proven) within the first few months. Those may be re-treated.

PCLegacy said...
As for thermal damage, I am pretty sure the way the system works there are temperature limits you can set that automatically shut down the laser in order to avoid "cooking" adjacent structures.

The second law of thermodynamics - entropy - tells us that heat travels. In spite of some very sophisticated techniques (with FLA they surround the laser with cooling catheters and use thermal feedback to shut it off when heat rises), it is unavoidable that heat will penetrate and possibly damage adjacent structures. I know Dr. Marks is very careful about patient selection for that reason (he told me so - he's my Uro), but I don't know how many practitioners in community practice are as careful. Caveat emptor!

This is why if one wants to have it done, one has to start with a very careful analysis of the treatment area, and if there are any critical structures nearby, a non-thermal ablation technique may be a better option.

I'm not against focal ablation, although I think it's a better idea for men with GS 3+4 index tumors than GS 3+3 (who are still good candidates for AS). I just think one should be aware of the downsides and be careful about choosing therapists.