Brachytherapy for Prostate Cancer Not Just Another Gimmick

AMELIA ISLAND, Fla--Is brachy-therapy for prostate cancer a ‘gimmick’ or a new treatment technique with numerous advantages over either radical prostatectomy or external beam radiotherapy? Very definitely the latter, Jay Friedland, MD, of the H. Lee Moffitt Cancer Center, Tampa, said at the Southern Association for Oncology (SAO) 11th annual meeting.

Brachytherapy is the transperineal TRUS (transrectal ultrasound)-guided interstitial implantation in the prostate of permanent radioactive "seeds" at the site of neoplastic tissue.

The two radiation treatments used most often in prostate cancer today are high-dose 3D conformal radiotherapy and brachytherapy, Dr. Friedland said. "However, I find in my travels that most people don’t understand brachytherapy," despite an improved understanding of prostate cancer in recent years.

For example, he said, physicians now know that the pubic arch and prostate comprise a 3D structure and that the prostate is composed of different zones. Seventy percent of all prostate cancers occur in the peripheral zone, which wraps around the outside of the prostate; 20% to 25% occur in the transitional zone; and only 5% develop in the central zone. The placement of the seeds is planned so as to give an appropriate radiation dose to each of the different zones of the prostate, he said.

Exclusion criteria for brachytherapy are similar to those for radical pros-tatectomy: high PSA level (more than 20 ng/mL), large prostate, pubic arch interference, and inability to receive either spinal or general anesthesia.

Prostate brachytherapy was initially a "patient driven" technique, Dr. Friedland noted, but over the last several years, the medical literature in support of the treatment has begun to catch up with patients’ perceptions of its value.

"A careful review of the medical literature reveals that, if one uses PSA as the endpoint for successful therapy, there are published data with essentially equivalent follow-up (5 to 8 years) for prostate brachytherapy, external beam radiotherapy, and radical prostatectomy," Dr. Friedland said. "The outcomes for all three are essentially the same in patients with PSA levels less than 10 ng/mL, Gleason score of 6 or less, and T2a or lower tumor stage."

For patients with parameters greater than the above, radical prostatectomy and brachytherapy are equivalent, he said, while conventional external beam radiotherapy is inferior. In addition, Dr. Friedland pointed out, brachytherapy has the most favorable toxicity profile of all the treatment options.

"It is my belief that brachytherapy is not only an excellent treatment option but the ultimate in conformal prostate radiotherapy," he said.