Radiation Therapy for Prostate Cancer
Treating Physicians: Dr. Rahul R Parikh, Dr. Ronald Ennis, Dr. Lara Hathout
Prostate cancer is the most common malignancy in American men.
- About 170,000 new cases of prostate cancer each year, making it the number one type of cancer in men.
- Nearly 29,000 men died from prostate cancer each year.
- More than 75 percent of prostate cancer is diagnosed in men over age 65.
Stereotactic Body Radiotherapy for Prostate Cancer
Robert Wood Johnson University Hospital is advancing the use of an extremely precise, high-dose form of radiation therapy for prostate cancer called stereotactic body radiotherapy (SBRT). SBRT uses innovative imaging technologies combined with a sophisticated computer system (similar to the CyberKnife® system) to deliver intense doses of radiation to prostate tumors with extraordinary accuracy, minimizing damage to healthy tissue. SBRT can deliver your treatment in 10 minutes or less, and the entire treatment may be completed in as few as five sessions. Cyberknife® treatments may take three to five times longer, per treatment, to deliver the same dose of radiation.
RWJ radiation oncologist Rahul R. Parikh, M.D. has found SBRT to be extremely effective for many of his prostate patients. He has successfully treated patients with this approach, with similar side effects to conventional radiation techniques and with excellent immediate and long-term results.
Risk Factors For Prostate Cancer
Incidence of prostate cancer increases with age.
- Median age at diagnosis in Caucasian males is 71.
- African-American men have the highest incidence of prostate cancer in the world.
- Heredity accounts for 5 to 10 percent of cases.
Screening For Prostate Cancer
According to the American Cancer Society, men aged 50 or older should be offered a digital rectal exam (DRE) and a PSA blood test. However, it is a good idea to visit your doctor earlier to establish a baseline PSA level so you can monitor changes.
- Prostate specific antigen (PSA) is a valuable marker for prostate cancer although BPH or infection may also cause a rise in PSA.
- Normal range is 0-4, however, a PSA above 3 in men younger than 60 may be considered abnormal.
- African-American men and men with a family history of prostate cancer should be examined beginning at an earlier age.
Diagnosing Prostate Cancer
Prostate cancer is most often diagnosed through a blood test measuring the amount of prostate specific antigens (PSA) in the body. However, signs and symptoms of prostate cancer can include:
- Changes in urinary flow: Frequency, urgency, hesitancy.
- Frequent nighttime urination.
- Painful urination.
- Blood in urine.
Other conditions that may cause these symptoms include an enlarged prostate (benign prostatic hypertrophy or BPH) or infection.
Radiation Therapy Options for Treating Prostate Cancer
After a diagnosis of prostate cancer has been established with a biopsy, the patient should discuss the treatment options with a radiation oncologist and a urologist. Radiation therapy treatment options to cure prostate cancer include:
- External beam radiotherapy.
- SBRT - Stereotactic Body Radiotherapy
- Prostate brachytherapy.
External Beam Radiation Therapy
External beam radiation therapy involves a series of daily outpatient treatments to accurately deliver radiation to the breast.
- Painless radiation treatments are delivered in a series of daily sessions. Each treatment will last less than 30 minutes, Monday through Friday, for five to seven weeks.
- The usual course of radiation treats only the breast, although treatment of the lymph nodes around the collarbone or the underarm area is sometimes needed.
- 3-dimensional conformal radiotherapy (3D-CRT) combines multiple radiation treatment fields to deliver very precise doses of radiation to the breast and spare surrounding normal tissue.
- Intensity modulated radiation therapy (IMRT) is a form of 3D-CRT that further modifies the radiation by varying the intensity of the radiation beams. It is currently being studied for treating breast cancer.
- Side effects might include skin irritation, like a mild to moderate sunburn, mild to moderate breast swelling and fatigue.
Prostate brachytherapy, better known as a seed implant, is often done in the operating room.
There are two methods of delivering internal radiation for prostate cancer:
- Permanent seed implants.
- High-dose rate temporary seed implants.
These treatments are designed to deliver a very high dose of radiation to the tumor by inserting radioactive seeds directly into the prostate gland under ultrasound guidance while the patient is under anesthesia. Isotopes of iodine or palladium are most commonly used. The seeds are approximately four millimeters long and less than a millimeter in diameter. In certain situations, both prostate brachytherapy and external radiation may be recommended to combat the tumor.
The side effects from seed implants are similar to those experienced with external beam radiotherapy. Patients usually experience urinary frequency and discomfort in urination. These effects may be lessened with medication and usually dissipate over the course of three to six months.
Proton Beam Therapy
A Proton Beam Machine will be installed in Robert Wood Johnson University Hospital in near future. In a few parts of the country, proton beam therapy is being used to treat prostate cancer.
Proton therapy is administered much the same way as external beam therapy, but it uses protons rather than x-rays to irradiate cancer cells.
Certain patients may benefit from hormone therapy in addition to radiation. In some patients, hormone therapy works with radiation therapy to improve cure rates.