Patients who want to pursue brachytherapy as first line monotherapy, meaning alone and without other treatments, should exhibit these characteristics:
- Gleason score 6 or lower
- PSA level 10 or lower
- DRE suggests no extension outside of prostate gland
- No history of benign prostatic hyperplasia
- Prostate gland volume below 60 grams or 60 cc
Not meeting all of these criteria, however, does not eliminate brachytherapy as a prostate cancer treatment option. Read on to see who else is opting for brachytherapy and why. Then speak with your doctor to see if brachytherapy is right for you.
Brachytherapy as Initial Monotherapy for Prostate Cancer
Prostate cancer should be confined to the prostate for those considering interstitial radiation therapy. This treatment is most effective when the disease is confined within the cloud of radiation created by the radioactive pellets. In most patients, the cloud of radiation will extend about 5 mm outside the organ.
Patients who want to pursue brachytherapy as their primary treatment should have Gleason scores of 6 or less and PSA scores of 10 or less. They should also have prostate volumes which are below 60 grams or 66 cc. Those with benign prostatic hyperplasia (BPH) are not candidates for prostate brachytherapy. The urinary side effects associated with brachytherapy are exacerbated if the patient already has BPH.
Finally, all candidates for brachytherapy should have a digital rectal exam (DRE) that suggests that the tumor has not extended out of the prostate gland. Because of the cloud of concentrated radiation that the radioactive seeds create, some early extension outside of the prostate does not eliminate some patients from brachytherapy.
Neoadjuvant Hormone Therapy and Brachytherapy
Hormone therapy is sometimes used as neoadjuvant therapy for brachytherapy patients. Neoadjuvant refers to a treatment that is given before the primary treatment to maximize effectiveness. Depending on the size of the prostate gland, hormone therapy is given anywhere from 3 to 6 months before brachytherapy. The use of hormones can shrink the prostate gland so that the prostatic volume is acceptable for brachytherapy, unless the patient's prostate gland is severely enlarged (over 100 cc).
Multiple Radiation Therapies
Doctors, however, will still use brachytherapy for patients who do not meet the above requirements. Internal radiation therapy is sometimes used with external radiation therapy, including intensity modulated radiation therapy (IMRT) and external beam radiation therapy (EBRT). External radiation therapy is rarely used if brachytherapy fails because the pellets are more powerful than external beams. If early prostate cancer survives interstitial radiation therapy, the cells are most likely radioresistant.
Ages of Brachytherapy Patients
While brachytherapy is an effective prostate cancer treatment option, men who are much younger and in good health and who can reasonably expect to live another 20 years, may want to consider other treatments. Most of the conclusive data in LDR or HDR therapy does not extend past the twenty year mark. Most long-term studies do not extend past 10 to 15 years.
For patients who are older and are wondering if they can tolerate this form of radiation therapy, should consider that age is only a relative factor when choosing a prostate cancer treatment. Patients should take into account their general state of health before making a decision.
Other Factors in the Brachytherapy Decision
Patients who are obese should talk with their doctors about whether brachytherapy is right for them. The needles and the catheters used in the minimally invasive procedure may not be able to withstand higher weights and still be effective for seed implantation.
Patients should have a pubic arch evaluation, which determines whether or not a patient has pubic arch interference. The pubic bones grow together to form a "V", which is in front of the prostate gland. A narrow pubic arch can make prostate seed implantation difficult. Patients with pubic arch interference may want to consider other prostate cancer treatments.
Patients who have undergone transurethral resection of the prostate or TURP before, may not be good candidates. If too much of the prostatic tissue was removed during TURP, then there may be insufficient tissue left to plant the radioactive seeds.