Analysis of imaging characteristics of undifferentiated carcinoma with pancreatic osteoclast-like giant cell / 中华消化杂志

ABSTRACT

Objective:To investigate the imaging characteristics of computed tomography (CT) and magnetic resonance imaging (MRI) of undifferentiated carcinoma with pancreatic osteoclast-like giant cell (UPC-OGC).Methods:From April 2015 to November 2019, at Zhongshan Hospital, Fudan University, 11 pathologically confirmed UPC-OGC patients who received upper abdominal CT or MRI before surgery and with complete clinical and pathological data were retrospectively included. The imaging characteristics of CT and MRI were analyzed, which included lesion location, number, shape, size, boundary, plain scan and enhancement features, adjacent tissue invasion and metastasis. Independent sample t test was used for statistical analysis. Results:The tumor lesions of 11 patients with UPC-OGC were all single, and the maximum diameter of lesion was (4.84±2.96) cm (ranged from 2.00 to 12.80 cm). The lesions of 7 patients with UPC-OGC were located in the head of pancreas, 2 located in the body of pancreas, 1 located in the tail of pancreas and 1 located in the junction of body and tail of pancreas. The lesion shapes of 3 patients with UPC-OGC were round, and the lesion shapes of 8 patients were oval with lobulation. The lesion boundaries of 8 patients with UPC-OGC were clear and the lesion boundaries of 3 patients were unclear. Seven patients with UPC-OGC were examined by plain and enhanced CT scan. Plain CT scan showed that the density of solid area of the tumor was similar to that of normal pancreatic parenchyma ((37.14±6.10) HU vs. (43.14±4.55) HU), and the difference was not significant ( t=-2.85, P=0.097). Contrast-enhanced CT scan in arterial phase showed that the degree of enhancement in solid area of the tumor was weaker than that of normal pancreatic parenchyma ((67.29±12.79) HU vs. (90.43±9.81) HU), and the difference was statistical significant ( t=-4.10, P=0.004), while contrast-enhanced CT scan showed that in venous phase the solid area of the tumor continued to strengthen and the degree of enhancement was similar to that of normal pancreatic parenchyma ((84.71±15.30) HU vs. (79.57±10.73) HU), and the difference was not significant ( t=0.38, P=0.535). Both CT and MRI enhanced scans showed uneven enhancement of the lesions, the degree of enhancement of solid component in arterial phase was slightly weaker than that of normal pancreatic parenchyma and the marginal and internal separation were progressively enhanced, and the degree of enhancement in the venous phase and balanced phase was slightly higher than that of the normal pancreatic parenchyma or similar to that of the normal pancreas. Conclusions:The imaging of CT and MRI of UPC-OGC have certain characteristics, which are helpful for the diagnosis and identification of the disease.