Clinical Perspectives

Fiducial Markers Support Image-Guided Radiation Therapy

October 01, 2019


Fiducial markers can help improve radiation treatment for some gastrointestinal cancer patients. Gastroenterologists in Moffitt's Gastrointestinal Oncology Program are utilizing endoscopic ultrasound (EUS), to insert and place fiducial markers in tumors to support in image-guided radiation therapy.

A needle is loaded with fiducial and placed in or very near the tumor using real-time ultrasound guidance. For the patient, the procedure feels like a traditional endoscopy. Once the markers are placed, they can stay inside the tumor unless removed in surgery.

Candidates include pancreatic cancer patients with locally advanced, non-resectable disease. As well as, esophageal cancer patients who have had chemotherapy and undergo radiation therapy before surgery. Although fiducial markers have been typically used for pancreatic and esophageal cancer patients, they have also been used for rectal tumors, liver tumors and lymph nodes.

Dr. Jason Klapman, gastroenterologist and medical director of Endoscopy.

“A lot of times, tumors that are in the areas of the gastrointestinal tract move a lot,” said gastroenterologist Dr. Jason Klapman. “Tumors can move even with breathing, so it’s helpful to have these markers to guide oncologists so they know exactly where to radiate.”

The fiducial markers help provide precise targeted radiation treatment and a more focused dose to the tumor. It can also drastically reduce the amount of time a patient must undergo radiation treatment. In some cases, what would traditionally take five weeks of radiation can be administered in just five days.

Dr. Sarah Hoffe, section head of GI Radiation Oncology.

“These markers offer two major benefits for radiation oncologists,” said radiation oncologist Dr. Sarah Hoffe. “First, they identify the exact location of the tumor during each phase of the patient’s breathing cycle. Second, since imaging is available on the radiation treatment unit itself, they allow the radiation oncologist to ensure that the delivery is exactly in the right place every day. These two advantages enable smaller margins of normal tissues within the treated areas, leading to less side effects.”

While this use of fiducials has become more prominent, there are still questions regarding the technique. it is also still unknown if or how it will affect survival.