A milestone in prostate treatment
Cape Cod Hospital marked an important milestone on Aug. 12, 2020, when the 1000th prostate seed implant procedure was performed.
When the first seed implantation was done at the hospital close to 24 years ago, it was a novel approach to prostate cancer that few doctors in New England were trained to do. Radiation Oncologist Basia McAnaw, MD, was an exception. Dr. McAnaw was part of the first group of physicians to learn the procedure at a hospital in Seattle, Washington, where it originated. She then became the first radiation oncologist to perform the procedure in Massachusetts in February of 1993 at St. Elizabeth’s Medical Center in Boston.
On November 4, 1996, Dr. McAnaw came to Cape Cod from Boston to teach doctors how to do the first two seed implantations. She then moved to the Cape and joined Cape Cod Healthcare three years later and is now on staff at both hospitals. In addition to the 1,000 seed implantations done at Cape Cod Hospital, another 423 have been done at Falmouth Hospital.
Seed implantation, or brachytherapy as it is also called, is one of four possible treatment models for prostate cancer. It involves the insertion of a radioisotope – iodine 125 - within titanium seeds that are implanted directly into the tissue between the scrotum and the anus.
“The beauty of this procedure is that instead of radiation going through the normal anatomy of the body, such as the bladder and rectum, the seeds are placed directly into the prostate and don’t interfere with the bladder or rectum,” she said. “That’s an advantage. And because they don’t interfere significantly or to any great degree with the bladder or rectum, you can give a higher dose of radiation to the prostate and that provides a high cure rate.”
Data shows a cure rate as high as 95 percent with limited long-term complications for early stage prostate cancer, she said.
One of the other advantages is that the treatment is short. It takes place in just one morning and the patient is given general anesthesia, so seed implantation is painless.
But the procedure is not appropriate for all patients. For example, it would not be appropriate for an older man with a large prostate and bad urinary symptoms. Seed implantations are also not an appropriate treatment for patients with advanced cancer.
“Each treatment has their pros and cons and each of them is suitable for different patients,” Dr. McAnaw said. “I think each patient has certain characteristics which make him a candidate for a different type of therapy. The patient should have the right to choose an option that is right for him.”
The least intrusive treatment is expectant management or watchful waiting. Basically, that just means that the patient and his care team observe his PSA numbers over the years and don’t do anything unless there is a change in the aggressiveness of the cancer. This is a very appropriate treatment model for men with early stage prostate cancer, especially if the patient is older.
“Prostate cancer is usually slow growing for the first decade or so and then it starts to pick up speed,” Dr. McAnaw said. “So, if a man is diagnosed with prostate cancer when he’s 80 and he’s got early stage cancer, doing nothing would be very prudent because he’ll likely die of something else before he’ll die of prostate cancer. But when a man gets diagnosed in his 50s or 60s with prostate cancer and it’s showing signs of becoming more aggressive, he should consider all of the options available.”
Another treatment used by radiation oncologists is external beam therapy. The most common form of external beam therapy is Intensity Modulated Radiation Therapy or IMRT. This treatment is a good option for older men who are not good candidates for surgery because it is what Dr. McAnaw calls “a relatively gentle treatment” with few side effects.
Some patients might feel the need to urinate slightly more frequently and they may experience some gas or mild fatigue. The cure rate is good, Dr. McAnaw said, but the dose has to be limited because if it is too high, it can damage the rectum or bladder. Treatment is 15 minutes a day, five days a week for six to eight weeks.
IMRT would be a good treatment choice for a man who is 75 whose tumor has started to grow and become more aggressive. It’s a particularly good option for men who have larger prostates and urinary symptoms.
The surgical option, radical prostatectomy, also has a very high cure rate. It is an appropriate option for men younger than 70 who would feel psychologically better by having the offending organ and cancer removed entirely. Surgery does have some side effects that are not well tolerated. There is a risk of incontinence and the possibility of eliminated or decreased sexual function with surgery. Patients have a longer recovery period and need to have a catheter in place for two weeks.
For patients with advanced prostate cancer, a combination therapy gets the best results, Dr. McAnaw said. First, they would get IMRT therapy for five weeks, followed by seed implantation five weeks later. They would also receive androgen deprivation therapy to remove testosterone so the cancer cells are more amenable to the radiation.
“I think the more information a patient has the better they can make a choice,” Dr. McAnaw said. “There is no right or wrong answer. What’s right for one patient might not be right for another patient. Everyone has the right to make their own choice based on their particular situation.”