Posted: Wednesday, September 20, 2023
The results of a 5-year, single-center study of nearly 800 patients published in BMC Medical Imaging support the feasibility, safety, and reliability of fiducial marker implantation for image-guided radiotherapy in men with prostate cancer, according to its authors. Ali Mahdavi, MD, of Shahid Beheshti University of Medical Sciences, Tehran, Iran, and colleagues noted that to their knowledge, this was the largest analyzed series of intraprostatic fiducial marker insertions to date.
Fiducial markers facilitate the tracking of inter- or intrafraction prostate motions, as well as volume changes, which may ultimately improve the results of external-beam radiation therapy. Not being aware of gland displacement could mean a target is missed, secondary to prostate motion during radiotherapy, the authors indicate. Men with or without a history of radical prostatectomy were eligible, as long as they were candidates for image-guided external beam radiotherapy.
Via transrectal ultrasonography guidance, every patient had three gold fiducial markers, each measuring 3 × 0.6 mm, inserted through an 18-gauge Chiba needle. The authors noted that marker migration very rare, and “when it does occur, the effect is negligible.”
“Using narrow needles (18-gauge) can reduce the [potential] immediate complications, such as urinary retention and pelvic hematoma,” Dr. Mahdavi and co-investigators explained. Further, they continued, appropriate bowel preparation and irrigation with povidone-iodine in conjunction with broad-spectrum antibiotics may reduce the possibility of sepsis.
Not only were all procedures in the January 2018 to January 2023 time frame completed successfully, but all patients tolerated the procedure with minimal discomfort, the team stated. Only two patients experienced marker migration shortly after marker insertion, and no fiducial marker migration was reported throughout radiotherapy. The rates of sepsis and transient urinary obstruction after the procedure were 1% and 1.6%, respectively.
Disclosure: The study authors reported no conflicts of interest.