As magnetic resonance imaging technology continues to advance year after year, so does MRI’s ability to accurately detect pancreatic cysts, according to a new study published in the April issue of Clinical Gastroenterology and Hepatology (doi: 10.1016/j.cgh.2015.08.038).
“To our knowledge, this is the first study to analyze the relationship between the technical improvements in imaging techniques (specifically, MRI) and the presence of incidentally found PCLs [pancreatic cystic lesions],” said the study authors, led by Dr. Michael B. Wallace of the Mayo Clinic in Jacksonville, Fla.
Dr. Michael B. Wallace
Dr. Wallace and his coinvestigators launched this retrospective descriptive study selecting the first 50 consecutive abdominal MRI patients at the Jacksonville Mayo Clinic during January and February of each year from 2005 through 2014, for a total of 500 cases who met inclusion criteria included in the study. Patients were excluded if they had preexisting symptomatic or asymptomatic pancreatitis, either acute or chronic, pancreatic masses, pancreatic cysts, pancreatic surgery, pancreatic symptoms, or any pancreas-related indications found by MRI.
The clinic underwent periodic MRI updates over the course of the 10-year study, along with requisite software updates to “take advantage of the new hardware technology,” the study explains. Major hardware improvements, provided by Siemens Medical Solutions USA, were Symphony/Sonata, Espree/Avanto, and Aera/Skyra, while software updates corresponding to each hardware update were VA, VB, and VD, respectively.
SOURCE: AMERICAN GASTROENTEROLOGICAL ASSOCIATION
Furthermore, each software update had other, smaller upgrades, leading to a total of 20 combinations of MRI hardware and software on which MRIs were performed over the 10 years. Every MRI taken included “an axial and a coronal T2-weighted single-shot (HASTE) pulse sequence [with] TR 1400-1500 ms, TE 82-99 ms, and slice thickness 5-7 mm (gap, 0.5-0.7 mm).” Each MRI was analyzed by a pancreatic MRI specialist to find incidental cysts.
The number of patients found with pancreatic cysts increased incrementally from 2005 to 2014, with 2010 being the year with the highest number. A total of 208 subjects (41.6%) were found to have incidental cysts, but only 44 of these cases were discovered in the original MRI. The presence of cysts was associated with older age in patients who had them; only 20% of all subjects under 50 years of age had cysts, compared to 32.4% of those between 50 and 60 years, 54.9% of those between 60 and 70 years, and 61.5% of those over the age of 70 years (P less than .01).
Additionally, 56.4% of all subjects with diabetes (P less than .01), 59.0% of subjects with nonmelanoma skin cancer (P less than .03), and 58.1% of those with hepatocarcinoma (P less than .02) were also found to have cysts. Most striking, however, is that newer hardware and software permutations were able to detect cysts in 56.3% (Skyra) of patients who had them, compared with only 30.3% (Symphony) of patients who underwent MRI on older technology.
“The variable field strength” (1.5 T vs. 3 T) was not significantly related to the presence of PCLs,” Dr. Wallace and his coauthors concluded. “We believe this may be secondary to the lack of power of the analysis, because only 6% of the examinations were 3-T studies. Therefore, we speculate that this relationship may be confirmed if the number of 3-T studies increased.”
Males and females each made up roughly 50% of the study population, with a median age of 60 years and 85% being white. Additionally, 4% of subjects had a family history of pancreatic cancer, 12% had a personal history of solid organ transplant, and 53% had a personal history of smoking.
This study was funded by the Mayo Clinic. Dr. Wallace disclosed that he has received grant funding from Olympus, Boston Scientific, and Cosmo Pharmaceuticals, and travel support from Olympus. No other authors reported any financial disclosures.