Brachytherapy for Prostate Cancer Tied to Heightened Long Term Risk of Secondary Malignancies
By Dr. David Samadi
Prostate cancer treatment, mainly through radiation therapy, presents a complex landscape where the very treatment aimed at eradicating cancer cells may inadvertently trigger the development of new tumors later on. The mechanism behind this lies in radiation, which disrupts the DNA of cancer cells but can also inflict genetic damage on neighboring healthy cells, potentially leading to the emergence of secondary malignancies over time.
Around a decade ago, Canadian researchers embarked on a journey to explore the risk of secondary malignancies among men with prostate cancer who underwent brachytherapy, a form of radiation therapy distinguished by radioactive seeds that are directly implanted into the tumor site. This approach, though offering the advantage of a single outpatient treatment session, has declined in popularity due to the emergence of newer external beam radiation techniques boasting higher precision and fewer side effects.
Study methods and results
The study in question meticulously compared rates of secondary malignancies within the pelvic region among men treated with either brachytherapy or prostatectomy (surgical removal of the prostate). Conducted in British Columbia between 1998 and 2000, the study cohort comprised 2,418 brachytherapy-treated men with an average age of 66, and 4,015 surgically-treated men averaging 62. Subgroups within the surgical cohort included those treated solely with surgery and others who underwent surgery followed by external beam radiation.
Initial findings, published in 2014, suggested no discernible difference in secondary malignancy rates between the groups or compared to the general population’s cancer incidence. However, updated results released in April 2024 painted a contrasting picture. The brachytherapy group exhibited higher rates of pelvic secondary cancers, notably in the bladder and rectum. At 15 years of follow-up, 6.4% of brachytherapy-treated men developed secondary malignancies, a figure that rose to 9.8% after 20 years. In comparison, surgically treated men experienced lower rates, with 3.2% and 4.2% developing pelvic secondary malignancies over similar follow-up durations. Remarkably, the two treatment groups had no discrepancy in secondary malignancy-related deaths.
Of particular concern is the strength of association with bladder cancer, mirroring the risk level observed with smoking. These findings carry significant implications for the treatment landscape of localized prostate cancer, especially for patients with extended life expectancies.
Expert commentary on the study highlights a sobering reality regarding radiation therapy for prostate cancer, underscoring a long-suspected correlation between radiation and heightened risks of secondary malignancies as time elapses. These malignancies typically manifest in neighboring organs such as the bladder, rectum, or even within the prostate itself.
While often treatable, they represent a lingering consequence of radiation therapy, prompting a reassessment of treatment approaches for younger patients with considerable life expectancies. Moreover, the study underscores the importance of diligent follow-up visits to monitor and address potential long-term consequences.
Takeaway message
The concerning rise in long-term secondary malignancies underscores the need for patients to weigh the potential risks and benefits comprehensively when considering brachytherapy as a treatment option for prostate cancer. This is particularly relevant given the availability of alternative therapies that offer comparable efficacy with potentially fewer urinary side effects, thus necessitating informed decision-making in prostate cancer management.
Dr. David Samadi is the Director of Men’s Health and Urologic Oncology at St. Francis Hospital in Long Island. He’s a renowned and highly successful board certified Urologic Oncologist Expert and Robotic Surgeon in New York City, regarded as one of the leading prostate surgeons in the U.S., with a vast expertise in prostate cancer treatment and Robotic-Assisted Laparoscopic Prostatectomy. Dr. Samadi is a medical contributor to NewsMax TV and is also the author of The Ultimate MANual, Dr. Samadi’s Guide to Men’s Health and Wellness, available online both on Amazon and Barnes & Noble. Visit Dr. Samadi’s websites at robotic oncology and prostate cancer 911.