Thursday, January 1, 2004
Radiation First, Then Seed Implant: More Ammunition to Support this Sequence in the Treatment of Prostate Cancer
Perhaps the most contested issue in the combination of external beam radiation with radioactive seed implant treatment for prostate cancer has been the order in which the two therapies are delivered. There have been strong opinions on both sides. With the recent publication of “Increased Expression of PSA mRNA During Brachytherapy in Peripheral Blood of Patients with Prostate Cancer” in the journal Urology (Urology 60:270-275, 2002) compelling evidence now exists to put the issue to rest. The authors cite a 25-patient study in which peripheral blood was collected before, during and after brachytherapy. Twenty-three of these patients were tested negative for circulating prostate tumor cells (by using reverse transcriptase-polymerase chain reaction analysis) prior to brachytherapy. Fifteen of those men (65%) turned positive during or after the brachytherapy. Eight of the participants developed a rising serum PSA following brachytherapy. Only one man did not have a PSA mRNA expression in the peripheral blood before, during or after brachytherapy.
These findings strongly suggest that the process of brachytherapy itself leads to the shedding of prostate cells into the bloodstream, dramatically increasing the risk of metastatic deposits and systemic failure, as measured by serum PSA levels.
Michael Dattoli, MD has always theorized that the insertion of brachytherapy needles into a tumor site had the potential to introduce cancerous cells into the bloodstream. This latest Urology publication has now quantified this theory.
In developing his highly successful radiation-then-seeds protocol, Dattoli has utilized IMRT radiation to not only defeat the active cancer cells within the prostate, but to in essence, sterilize the surrounding field. This approach serves to create a barrier beyond which any brachytherapy “liberated” cancer cells are not likely to survive.