The ASCENDE-RT Study
The ASCENDE-RT (Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy) study was the first randomized clinical trial comparing brachytherapy to the traditional use of external beam radiation therapy to treat intermediate and high risk Prostate Cancer patients over a period of between 6 to 9 years.
The results show a significant increase in survival rates with an average of 50% of patients showing progression free survival when treated with LDR brachytherapy.
LDR brachytherapy is a form of radiation treatment that is a 45-minute procedure to place tiny radioactive “seeds” directly into the prostate.
The trial involved 398 patients, all of which had been diagnosed with intermediate or high-risk prostate cancer. They had no prior surgery or radiation treatment and their pre-trial PSA had to have been less than 40 to take part. The patients were randomly split into two groups.
200 of the 398 patients were in group 1. Their treatment comprised of 12 months continuous androgen deprivation therapy (ADT – a type of hormone therapy) and then, starting 8 months after initiation of the ADT, 4.2 to 5 weeks of external beam radiation (DE-EBRT) followed by an external beam radiation boost lasting 3.2 to 4 weeks.
The other 198 patients were in group 2. Similarly, their treatment comprised of 12 months continuous androgen deprivation therapy (ADT) and then, starting 8 months after initiation of the ADT, 4.2 to 5 weeks of external beam radiation followed by low-dose rate brachytherapy using permanently implanted seeds (carried out 14 to 25 days after the last external beam treatment).
Study Results
In summary, the trial demonstrated a 50% decrease in biochemical relapse, shown through PSA results being lowered and maintained over a year period of between 6 to 9 years) with the use of LDR brachytherapy in conjunction with hormones and whole pelvis radiotherapy when compared to using DE-EBRT with the same treatments in patients assigned at random to each group
LDR brachytherapy has always been recognized as a successful, minimal side effect profile treatment for low risk prostate cancer patients however ASCENDE-RT study proves that intermediate and high risk patients should also be treated with LDR brachytherapy to benefit from increased long term bio-chemical free survival and quality of life benefits.
The study is extremely valuable in highlighting a need for change in clinical practice so that men with this type of disease get access to a treatment that gives them a fifty-percent better chance of being free of disease in the long term with less quality of life side effects.
The ASCENDE-RT study was a completely randomized study over a period of between 6 to 9 years, therefore giving results significant credibility.
Key Findings
Boosting prostate cancer patients with LDR brachytherapy shows an average of 50% increase in bio-chemical free survival rates for intermediate and high risk patients
80% of patients in group 2 had few or no long-term urinary side effects.
Of the intermediate risk patients in group 2 who received the LDR brachytherapy boost 93% showed progression free bio-chemical survival (PSA has not increased), compared to only 69% of patients in the other group.
Of the high risk patients in group 2 that received the LDR brachytherapy boost 78% showed progression free bio-chemical survival compared to only 58% of patients in the other groups