They are nearly microscopic, yet ganged together they can pack a big punch. They are microbeads embedded with radioisotopes and infused into body parts containing cancer tumors. The idea is to surround and destroy the tumor. The problem is making sure the microbeads stay put. SPECT/CT can provide the information to make it work.
They are nearly microscopic, yet ganged together they can pack a big punch. They are microbeads embedded with radioisotopes and infused into body parts containing cancer tumors. The idea is to surround and destroy the tumor. The problem is making sure the microbeads stay put. SPECT/CT can provide the information to make it work.
This novel form of radiotherapy, called radiomicrosphere therapy, offers new hope for patients with inoperable hepatic metastases or unresectable primary liver tumors (hepatocellular carcinoma or cholangiocarcinoma). The tiny beads packed with yttrium-emitting radioisotope might also buy some additional time for patients waiting for liver transplants by preventing tumor.
These benefits come only if the cancer-killing microbeads can be kept around the tumor. Unlike monoclonal antibody therapy, these beads are not naturally drawn to nor do they meld with the cancer. Instead they are infused in a nearby region and then carried via the circulatory system to the tumor. Normal flow would take them to the target and beyond, but the therapy calls for interventional radiologists to block their exit.
They do it by embolizing vasculature downstream from the tumor, usually with microcoils. SPECT/CT ensures this embolization has done the job before microbeads carrying the cancer-killing isotopes are infused.
In essence, a dry run is performed with microbeads carrying technetium instead of the yttrium isotope. SPECT CT tracks them, documenting flow to and, hopefully, not away from the tumor. Of particular concern when treating patients with liver cancer is to spot extrahepatic shunts that would take the microbeads to the lung and gastrointestinal tract.
In a study reported last week at the molecular imaging meeting of the SNM, SPECT/CT detected such possible extrahepatic shunting in 23 of 99 patients at the Cleveland Clinic in Cleveland, Ohio. By comparison, planar nuclear imaging spotted shunting in only nine of these 23 patients.
In one patient, the imaging hybrid found that the liver cancer had grown into and was obstructing the hepatic vein through which the microbeads were to be delivered.
Seeing such obstructions allows the treatment to be modified, according to the Cleveland Clinic researchers, just as spotting extrahepatic shunting will identify patients who need further embolization before the actual radiotherapy begins.
Can Photon-Counting CT be an Alternative to MRI for Assessing Liver Fat Fraction?
March 21st 2025Photon-counting CT fat fraction evaluation offered a maximum sensitivity of 81 percent for detecting steatosis and had a 91 percent ICC agreement with MRI proton density fat fraction assessment, according to new prospective research.
The Reading Room Podcast: Current Perspectives on the Updated Appropriate Use Criteria for Brain PET
March 18th 2025In a new podcast, Satoshi Minoshima, M.D., Ph.D., and James Williams, Ph.D., share their insights on the recently updated appropriate use criteria for amyloid PET and tau PET in patients with mild cognitive impairment.
Strategies to Reduce Disparities in Interventional Radiology Care
March 19th 2025In order to help address the geographic, racial, and socioeconomic barriers that limit patient access to interventional radiology (IR) care, these authors recommend a variety of measures ranging from increased patient and physician awareness of IR to mobile IR clinics and improved understanding of social determinants of health.
AI-Initiated Recalls After Screening Mammography Demonstrate Higher PPV for Breast Cancer
March 18th 2025While recalls initiated by one of two reviewing radiologists after screening mammography were nearly 10 percent higher than recalls initiated by an AI software, the AI-initiated recalls had an 85 percent higher positive predictive value for breast cancer, according to a new study.