PMC9909430_01
Abdominal enhanced CT manifestations of the lesions in the liver. (A1-3) On a plain CT scan, a poorly defined low-density lesion could be seen in the S4b and S5 segments of the liver. In the arterial phase (B1-3) and venous phase (C1-3) of a contrast-enhanced CT scan, the lesions showed continuous and obvious enhancement, while in the delayed phase (D1-3) the enhancement of the lesions decreased, and the density was similar to that of the normal liver, as shown by the black arrow.
fonc-12-1031112-g001.jpg
PMC9909430_01_fonc-12-1031112-g001.jpg
f1
Figure 1 ). Further examination revealed that the levels of neuron-specific enolase (NSE) of the patient were elevated ( Figure 2B ).
Preoperative planning and intraoperative status of patients. (A) According to the information from the two-dimensional enhanced CT image before operation, the hepatic lesion, the operative path (the black dotted line), and the resection area (the yellow area) were reconstructed by hand-drawing. (B) The tendency chart of NSE levels during patient follow-up. (C) Intraoperative gallbladder tumors (black arrow) and (D) corresponding CT images (black arrow). (E) Section of resected gallbladder tumor and part of the liver tissue, as shown, the black arrows indicate the gallbladder mass and the white arrow represents the liver tissue adjacent to the tumor (F) The wound condition after operation.
fonc-12-1031112-g002.jpg
PMC9909430_01_fonc-12-1031112-g002.jpg
f2
Figure 1 ). Further examination revealed that the levels of neuron-specific enolase (NSE) of the patient were elevated ( Figure 2B ). We planned to perform anatomical central hepatectomy, namely a territory resection around the middle hepatic vein ( Figure 2A ). During the operation we were surprised by the discovery of a gallbladder tumor rather than the liver lesion suggested by CT imaging ( Figure 2C ). Therefore, we quickly adjusted the operative protocol and performed a cholecystectomy, hepatoduodenal ligament lymph node dissection, and partial hepatectomy ( Figures 2E, F ). The bottom and body of the gallbladder had been filled with solid masses and enhanced significantly, whereas the density of the neck of the gallbladder was still normal ( Figure 2D ). Serum NSE levels showed a continuous downward trend ( Figure 2B ), and no obvious abnormality was found in biochemical tests and imaging examinations.
The microscopic pathological structure of tumor tissue. (A) The tumor was mainly located in the submucosa of the gallbladder (black arrow). (B) The white arrow shows normal liver tissue and the black arrow shows paragangliomas of the gallbladder tissue, in which tumor cells were diffusely distributed in clusters. (C) The gallbladder wall, which is surrounded by tumor cells, was covered with simple columnar epithelium structures (black arrow). (D) The paraganglioma demonstrated a characteristic zellballen architecture, rich in pink sinusoids inside (black arrow). Parts E and F show the junction structure of the tumor with adjacent liver tissues, and normal liver tissues all expressed the epithelial-derived markers Hepatocyto and CK-pan (white arrows), while non-epithelial paraganglioma tissue was negative (black arrows), which also indicated some degree of tumor invasion of the liver tissue.
fonc-12-1031112-g003.jpg
PMC9909430_01_fonc-12-1031112-g003.jpg
f3
Figure 3 ). Further detailed immunohistochemical analysis revealed that broad-spectrum pan-cytokeratin (CK-pan) antibody staining was negative, which means that the tumor originated from non-epithelial tissue.
Immunohistochemistry for the gallbladder paraganglioma. (A) The difference between neuroendocrine epithelial tumor (NET/NEC) and neuroendocrine non-epithelial tumor (PHEO/PARA) is that the former expresses broad-spectrum pan-cytokeratin (CK-pan), which was negative here, meaning that the tumor was of non-epithelial origin. (B-D) Traditional general neuroendocrine markers, including chromogranin A (CgA), neuron-specific enolase (NSE), and synaptophysin (Syn), were all positive. (E) S-100 staining highlights surrounding sustentacular cells. (F) The Ki-67 proliferation index of tumor cells was 10%. The typical positive expression of each marker in the figures is indicated by black arrows.
fonc-12-1031112-g004.jpg
PMC9909430_01_fonc-12-1031112-g004.jpg
f4
Chromogranin A (CgA), neuron-specific enolase (NSE), and synaptophysin (Syn), three important neuroendocrine markers, were all positive; S-100 highlighted surrounding sustentacular cells, and the Ki-67 proliferation index of tumor cells was 10% ( Figure 4 ).