Saudi J Gastroenterol. 2026 Jun 9. doi: 10.4103/sjg.sjg_91_26. Online ahead of print.
ABSTRACT
BACKGROUND: During follow-up of IPMN, attention should be paid to both IPMN-derived carcinoma and PDAC concomitant with IPMN (concomitant PDAC). Concomitant PDAC lacks clear risk factors and is often detected late. This study evaluated non-contrast MRI performance for early detection and identification of optimal imaging sequences.
METHODS: Patients histologically diagnosed with PDAC between May 2012 and March 2024 who underwent MRI at diagnosis were retrospectively included. PDAC located ≥5 mm from an IPMN was defined as concomitant PDAC. Cases of IPMC and main-duct IPMN were excluded. MRI sequences (T1WI, T2WI, MRCP, and DWI with ADC maps) were reviewed. Tumor detection was defined as (1) mass identification on T1WI/T2WI, (2) Main pancreatic duct (MPD) stricture or poor visualization with upstream dilatation on MRCP, or (3) hyperintense mass on DWI. Two radiologists independently evaluated all images.
RESULTS: Sixty-four cases (28 females; median tumor diameter, 21 mm) were analyzed. The median age at diagnosis was 74.5 years (interquartile range: 68-80 years), Blood test values showed median CA19-9 levels of 78 U/mL. The detection sensitivities by radiologists A and B were T1WI, 76.7%/68.3% (κ0.71); T2WI, 31.3%/29.7% (κ0.71); DWI, 71.4%/71.4% (κ0.87); and MRCP, 43.4%/35.8% (κ0.84). Combined sensitivities were 89.1%/82.8% for “T1WI and DWI” and 92.2%/85.9% for “T1WI, DWI and MRCP”.
CONCLUSIONS: Among single sequences, T1WI demonstrated the highest sensitivity. The combination of “T1WI, DWI, and MRCP” showed the highest sensitivity, although the differences were not statistically significant and should be interpreted cautiously for detecting PDAC concomitant with IPMN.
PMID:42301667 | DOI:10.4103/sjg.sjg_91_26
