Orlando, FL--In men with early-stage prostate cancer, permanent prostate seed implantation (PPI) appears to be as effective as high-dose conformal proton beam radiotherapy (CPBRT) in terms of biochemical control and reduction of PSA levels, according to findings from a new study.
The results may reassure patients that brachytherapy is a good treatment choice, according to the authors, from the University of California, San Francisco, Comprehensive Cancer Center. The findings were presented at the 2005 American Society of Clinical Oncology annual meeting here.
The UCSF group, led by Mack Roach, III, MD, retrospectively compared outcomes between men with early-stage prostate cancer treated with high-dose (79 GyE) conformal beam radiotherapy (196 patients) or permanent seed implants (218 patients). Among those receiving seeds, 28% also received short-term neoadjuvant hormonal therapy, 12% received external beam radiotherapy, and 14% received both.
The study found that patients treated with seed implants achieved lower PSA nadirs after treatment than those treated with conformal beam radiotherapy, with 89% of seed implant patients achieving a nadir PSA <0.5 ng/mL, compared with 50% of conformal beam patients, reported Dr. Roach, professor of radiation oncology and urology at UCSF.
Biochemical control similar Because of the retrospective nature of this study, no formal statistical comparison was performed between these groups. Of note, however, the estimated 5-year biochemical control among patients treated by seed implants and those undergoing conformal beam radiotherapy were 96% and 81%, respectively, at a median follow-up of 63 months and 48 months. For the permanent seed patients who also received neoadjuvant hormones, the 5-year biochemical control rose to 98%, compared with 94% in those who did not receive neoadjuvant hormones.
"Patients do really well with permanent seeds, both in terms of biochemical control and effect on PSA," said Vivian Weinberg, PhD, a biostatistician at USC. "They do at least as well with PPI as with CPBRT."
The authors suggest that the more dramatic reductions in PSA and high biochemical control at 5 years in the seed implant group may be due to the substantially higher doses given to these patients. When given alone, the minimum irradiation dose was 144 Gy in seed implant therapy, with nearly half of the prostate receiving a dose of more than 200 Gy. In patients who also received external beam therapy, a total dose of more than 145 Gy was used. In contrast, the total dose of radiation delivered by conformal beam radiotherapy was 79 Gy.
Given the cost and limited availability of conformal beam therapy, the results suggest that permanent seed implantation remains the better treatment option for early stage prostate cancer, according to the researchers.
"PPI is readily available around the country and is relatively inexpensive, but a proton machine costs more than $100 million and is only available in a handful of places," Dr. Roach said.
Seeds vs. prostatectomy: Long- and short-term side effects differ slightly
March 15th 2007For men with prostate cancer, radiation seed implants may yield a better short-term side effect profile than surgery, but surgery may offer slightly better long-term outcomes, new research from French radiation oncologists indicates.
Brachytherapy offers high 8-year prostate Ca survival rates
February 15th 2007More than 90% of men who receive appropriate radiation dose levels with permanent radiation seed implants to treat their prostate cancer are cured of the disease 8 years after diagnosis, according to a recent study in the International Journal for Radiation Oncology Biology Physics (2007; 67:327-33).
Research on bladder tissue regeneration progresses
February 1st 2007Atlanta-Tissue engineering research has grown by leaps and bounds in the past decade and a half, yielding findings that may someday have a profound impact on the field of pediatric urology. At the 2006 American Academy of Pediatrics Section on Urology annual meeting here, several groups presented cutting-edge data on novel systems for organ generation, including research demonstrating the feasibility of generating a functioning bladder from stem cells.
Radiation therapy combination prolongs long-term cure rate in men with PCa
January 18th 2007Three-fourths of men treated with a combination of radiation seed implants and external beam radiation therapy for prostate cancer are cured of their disease 15 years following their treatment, according to a study published in the International Journal of Radiation Oncology*Biology*Physics (2007; 67:57-64).
Cystectomy outcomes: Does surgeon's age matter?
October 1st 2006Ann Arbor, MI-Surgeon age is not a significant predictor of risk of mortality after cystectomy, according to the results of a recently published study from researchers at the University of Michigan, Ann Arbor (Ann Surg 2006; 244:353-62).