In honor of Prostate Cancer Awareness Month we sat down with our own Dr. Sibley for a Q&A on prostate cancer and brachytherapy.
What types of cancer can be treated using brachytherapy, and why is it used?
Although many cancers have been successfully treated with brachytherapy, common uses are for prostate cancer, gynecologic cancers and breast cancer. Unlike external beam radiotherapy, brachytherapy delivers radiotherapy through short-range radiation and must be placed within the target volume.
The short range of the radiation allows a degree of normal tissue sparing that is not achievable with traditional radiotherapy and much higher doses can be safely delivered to the target. However, brachytherapy is technically demanding, especially with prostate cancer, and results improve with experience...much like surgery.
How effective is brachytherapy in treating cancer?
Prostate brachytherapy is delivered alone for low-intermediate risk prostate cancers, and in combination with external beam for intermediate-high risk cancers. Across all stages and risk groups, prostate brachytherapy is equal or superior to the other common treatment modalities like robotic prostatectomy, IMRT (external beam radiotherapy), and proton radiotherapy. Low-risk prostate cancer patients have approximately a 90% likelihood of cure, regardless of the treatment they select. Brachytherapy compares favorably to surgery with a lower incidence of incontinence and impotence following treatment, but with a higher incidence of rectal and bladder irritation.
Is there a chemotherapy treatment for treating prostate cancer?
Since the male hormone testosterone stimulates growth of prostate cancer, “hormonal therapy”, which lowers testosterone, has successfully been used for decades. Chemotherapy has not traditionally been used for prostate cancer until late stages of the disease, typically when hormonal therapy has failed. However, this has all changed with the publication of a landmark study showing that docetaxel greatly improves survival in advanced prostate cancer when given early in the treatment course. Chemotherapy is now a component of treatment for many high-risk prostate cancer patients. In addition, many new chemotherapy and hormonal therapy drugs have recently been approved, or will soon be approved, that are changing the landscape of prostate cancer treatment.
How long does brachytherapy treatment last?
Depending on the isotope used, the half-life ranges from 10 days to 60 days. We prefer to use Cesium-131, which has a half life of 10 days. Patients who undergo brachytherapy with this isotope are back to back after 10 half lives, or 100 days, but never need to be isolated due to the short range of the radiation. Nevertheless, we recommend no prolonged, close contact with children or pregnant women (i.e. sitting on lap) for 1 month after the procedure.
Is brachytherapy painful?
Prostate brachytherapy is performed using 18 gauge needles, the same size needles as are used for prostate biopsies, except no tissue is removed with brachytherapy. Small titanium “seeds” containing the radioactivity are permanently implanted throughout the prostate using these needles. Pain is mild, and narcotics are not routinely prescribed postoperatively. Patients do not need to take time off work for this treatment. The procedure is performed under anesthesia, primarily because the patient needs to be perfectly still for 45 minutes to allow for precise placement of seeds. This is a low-risk procedure and is commonly performed in an outpatient surgery center setting.
Is surgery required before or after brachytherapy?
Prostate brachytherapy is an alternative to surgery. Patients who undergo surgery are not candidates for prostate brachytherapy, since there is no place to place the seeds. Surgery is occasionally performed following brachytherapy if the treatment fails, but salvage cryotherapy is much better tolerated and is preferred. Surgery following brachytherapy is, therefore, rare.
If you have questions or want to learn more about brachytherapy and how it works, contact us to schedule an appointment.