Medical Pike
Four years disease-free after radiation therapy
for prostate cancer close to cure, analysts claim
April 25, 2000. Few studies have looked at the long-term (8-10 years) efficacy of external
beam radiation treatment for prostate cancer until now. Researchers at Fox Chase Cancer Center
have published a study in the May issue of the journal Urology which suggests patients treated
with radiation therapy, who are disease-free at four years, remain disease-free.
"'Cure" is a powerful word when talking about the treatment of cancer, but this research allows us
to discuss radiation treatment of prostate cancer in that context," explains Alexandra L. Hanlon,
Ph.D., lead author of the paper. "We can comfortably tell a patient that if he remains disease-free
after four years, the chances of his cancer coming back are incredibly slim."
According to the study, patients treated with external beam radiation alone or in combination
with short-term hormone therapy (androgen deprivation) show little risk of failure after four
years. Ninety-nine percent of patients who show no evidence of recurrence five years after their
treatment, remain disease-free. None of those patients recurred after six years. The research
shows that if radiation treatment fails, as indicated by rising PSA levels, it does so in the first
three to four years following treatment. The median biochemical follow-up was 69 months for
patients receiving radiation alone and 60 months for the adjuvant hormone patients. All patients
had at least five years follow-up.
"If radiation treatment fails, it happens earlier for men who had a higher PSA level before
undergoing radiation therapy," Hanlon explains.
The risk of failure is greatest between 12 and 36 months, tapering to a low rate of failure at four
years. Treatment for men with an initial PSA of up to 10 failed at a median of 28 months.
Treatment for men with an initial PSA of 10 to 19.9 failed at a median of 25 months. And
treatment for men with an initial PSA of 20 and higher failed at a median of 22 months. The
latter group reaches low levels of disease recurrence at six years. In contrast, patients who have
a PSA level of less than 20 before treatment are less likely to recur beyond four years after
treatment.
Patients treated with external beam radiation and hormone therapy (androgen deprivation)
show a different pattern of failure, but a similar time frame for attaining a low risk of treatment
failure. The highest risk of failure occurs immediately following treatment, but declines to a low
risk of failure at 48 months.
Links
Fox Chase Cancer Center, one of the nation's first comprehensive cancer centers designated by
the National Cancer Institute in 1974, conducts basic and clinical research; programs of
prevention, detection and treatment of cancer; and community outreach. For more information
about Fox Chase activities visit their website at http://www.fccc.edu.
Other leading hospitals and comprehensive cancer centers are listed in our searchable links section starting at
http://www.psa-rising.com/caplinks.htm