Dear Dr. Roach: I completed proton therapy for prostate cancer in August 2021. Approximately nine months later, I began to bleed from my rectum. My oncologist suggested that I be treated by a colorectal surgeon, who recommended we try formalin. After 10 treatments, it became clear that this approach was not working, so he then suggested hyperbaric oxygen therapy.
I began treatment in mid-December 2022. After a few sessions, the clinic informed me that they would be closing for a 10-day holiday and resuming treatment in January. After an additional 19 sessions, I showed no signs of relief and quit the treatment. I began to suspect that since I did not receive at least two to three treatments per week during the two weeks the clinic was closed, this affected the outcome. What do you think?
Fortunately, my urologist recommended a gastroenterologist who treated me with argon plasma coagulation (APC), and after a colonoscopy and two sigmoidoscopies, I am 90% cured.
J.H.
Although radiation treatment for prostate cancer tends to have fewer side effects than surgery, one common side effect is radiation injury to the large intestine, particularly the rectum and sigmoid colon, the parts of the colon nearest to the anus.
Symptoms of chronic radiation injury typically begin months or years after the radiation. Both proton beam and standard radiation may cause radiation injury, with one comparative trial suggesting proton beam is more likely to cause this adverse effect.
I am very glad you have finally gotten relief. Hyperbaric oxygen was shown to have effectiveness (89% effective versus 63% in a “sham” control group), but no one treatment works for everybody. I can’t answer with certainty whether the two weeks you didn’t get treatment prevented effectiveness, but it certainly didn’t help. The fact that 19 additional sessions failed to give benefit suggests to me that you were one person destined not to benefit from this treatment.
APC delivered by a colonoscope or sigmoidoscope is often considered the most effective treatment, but your experience shows that it’s not always easy to choose the best treatment. Sometimes multiple specialists are needed for consultation.
Dear Dr. Roach: After my left knee replacement eight years ago, my doctor said to take four amoxicillin tablets an hour before every dental visit for two years. A few years later, another doctor did my right knee and said to do it for a lifetime, not just two years. Is it wise or necessary to take antibiotics so often? Just like me, the dentist wants to know why doctors don’t agree on whether to take antibiotics after two years.
R.J.
The guidelines weren’t as clear, but they are now. Antibiotics do not need to be given prior to a dental procedure in people with prosthetic joints, like a knee or a hip, even in the first few months or years after the joint replacement. There is good evidence now that dental procedures do not increase the risk of a prosthetic joint infection. Furthermore, there is good evidence that antibiotics do not reduce the risk of an infection after a dental procedure, even an invasive one.
These recommendations come both from the American Dental Association and the American Academy of Orthopedic Surgeons.
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to [email protected]
