Prostate cancer can be treated with surgery or radiation. There is no one best way. The radiation can be given by shooting a beam into the gland from a radiation source outside the body or by putting radioactive seeds into the prostate. The latter is a one-time event, with the patient treated as an outpatient.
There is no free lunch in cancer therapy. Many cancer therapies, especially chemotherapy, can cause a second cancer because of damage done to the genetic material, DNA, to adjacent normal tissues. Can this be a problem for men treated with radioactive seeds?
Marie St-Laurent and colleagues from British Columbia have looked at a large database from their province to see how men treated with surgery compare to those treated with needle implantation — so-called brachytherapy, and their results were published in the Journal of Urology. About 2400 men received brachytherapy, about 9000 underwent prostatectomy. They looked at the frequency of second malignancy overall and second malignancy in the pelvis, adjacent to the prostate — the bladder and the rectum. There was no overall difference in second non-pelvic malignancy; the most common cancer was lung cancer. There was, however, a statistical increase in cancer of the bladder and cancer of the rectum in men treated with brachytherapy — roughly a two-fold increase. Fortunately, the cancers were still uncommon and the death rate in the two groups from the pelvic cancers was no different, probably because the second cancers were found at an early stage. The management of the second cancers is challenging, because it is difficult to give radiation to the bladder or rectum once the prostate has been irradiated — out of concern for radiation poisoning.
So what is the take home message? There is a compelling need to follow these patients carefully for the development of second cancers. There is no free lunch with cancer therapy.