CT FINDINGS OF RARE PRIMARY HEPATIC TUMOR

Chen Jincan¹, Liao Weixiong², Wen Zhongyan¹, Liu Yong-Hui¹, Qiu Gan-Bin^{1, 2, *}

¹Department of Radiology, the first people's Hospital of Zhaoqing, Zhaoqing 506040, China - ²Imaging department of Zhaoqing Medical College, Zhaoqing 526020, China

Introduction: To investigate the CT image characteristics of primary hepatic tumor and tumor-like lesions, in order to improve the image diagnosis level of this kind of diseases. 

Materials and methods: the clinical data of 18 patients with rare primary liver tumors confirmed by pathology were collected. The CT image characteristics of the tumors were summarized by comparing the pathological results and analyzing the relevant literature. 

Result: there were 2 cases of inflammatory myofibroblastoma. The lesions were located under the liver capsule. The plain CT scan showed slightly low-density shadow, the enhanced CT scan showed mild to moderate enhancement, and the contrast medium gradually filled the center of the lesion in the delayed period; There were 2 cases of primary liver lymphoma, 1 case was mainly solid, and the other case was mainly cystic and solid. The solid components showed slightly low density, and the cystic area showed lower density. In the arterial phase of enhanced scanning, small vascular shadows were seen in the lesions, and the solid components showed mild enhancement. In the portal phase and delayed phase, the degree of vascular enhancement increased compared with the previous one. In typical cases, the sign of "vascular floating" was seen; In one case of inflammatory pseudotumor like follicular dendritic cell sarcoma, plain CT scan showed slightly low density, unclear boundary, obvious uneven enhancement of enhanced artery, continuous enhancement in portal phase and delayed phase, the degree of enhancement was lower than that of normal liver parenchyma, and pseudocapsule formation was seen around the lesion; One case of neuroendocrine carcinoma, with low-density space occupying in the right anterior lobe of the liver, obvious uneven enhancement of the enhancement artery, liquefied necrotic area, and "fast in and fast out" as a whole; There were 4 cases of carcinosarcoma. Plain CT scan showed multiple gravel like and small mass calcification in 1 case, no calcification in 3 cases, necrosis in varying degrees in 4 cases, obvious uneven enhancement of arteries, and no enhanced strip-like separation in some lesions; All 3 cases of hepatoblastoma showed huge space occupying changes, of which 2 cases showed exogenous growth, with fissure like low-density shadow in the center, obvious uneven septal enhancement in the arterial phase of enhanced scanning, thickened blood supply vessels and pseudocapsule formation in the focus in the delayed phase, further enhancement of solid components, and no enhancement in the central fissure like low-density area; 5 cases of undifferentiated embryonal sarcoma showed cystic and solid space occupying, some lesions broke through the capsule and grew outward, and the boundary was clear as a whole; Island, flake flocculent and cotton flocculent soft tissue density shadows were seen in the low-density area of some lesions, and uneven separation of thickness was seen. In one case, flocculent calcification was seen at the edge of the lesion, tumor neovascularization was seen in the arterial phase of enhanced scanning, and the edge of the lesion and the soft tissue and separation in the capsule were slightly enhanced; In portal vein stage and delayed stage, the development range of soft tissue lesions was expanded and continuously strengthened, and there was no enhancement of massive liquefaction necrosis in the capsule. 

Conclusion: primary rare liver tumors are difficult to diagnose before operation. CT findings of some lesions are specific and have certain value in diagnosis and differential diagnosis. The final diagnosis still depends on pathology.