Gastrointestinal stromal tumors in hepatic round ligament cysts: diagnostic utility of detective flow imaging

Abstract

Figures

Contrast-enhanced computed tomography reveals a cystic lesion with an enhanced, partially thickened wall (yellow arrowhead) adjacent to the gallbladder.

Endoscopic ultrasound shows a hypoechoic thickened wall in the cystic lesion.

Detective flow imaging shows an irregular vessel in the thickened wall, suggesting a malignant tumor.

Histopathological examination. a Cystic tumor with a thickened wall (yellow arrowhead). b, c Hematoxylin-eosin: A thickened wall is characterized by sheet-like proliferation of epithelioid cells admixed with spindle-shaped cells, displaying a palisading pattern.

Immunohistochemical staining of the tumor leads to the diagnosis of gastrointestinal stromal tumor. a Positive staining for CD117. b Negative staining for desmin. c Negative staining for S100.

Full text

Gastrointestinal stromal tumors (GISTs) arising within hepatic round ligament cysts are exceptionally rare, with limited literature available 1 , hence making their definitive diagnosis challenging. Detective flow imaging (DFI) is a novel endoscopic ultrasound (EUS) modality for differentiating malignancies by evaluating irregular vessels 2 3 4 5 . We report a case in which DFI was crucial for differentiating benign and malignant lesions, leading to a diagnosis of GIST within a hepatic round ligament cyst.

A 44-year-old woman was referred for the evaluation of a 30-mm cystic lesion adjacent to the gallbladder. The distinction between the gallbladder and cystic lesions on transabdominal ultrasonography was uncertain. Contrast-enhanced computed tomography revealed a cystic lesion with an enhanced, partially thickened wall ( Fig. 1 ). On magnetic resonance imaging, the gallbladder exhibited a low signal intensity, whereas the cystic lesion demonstrated a high signal intensity on diffusion-weighted image. This indicated that the cyst and gallbladder were discontinuous. EUS revealed a hypoechoic thickened wall in the cystic lesion ( Fig. 2 ). DFI revealed an irregular vessel in the thickened wall within the cystic lesion, suggesting a malignant tumor ( Fig. 3 ). Therefore, we decided to perform surgery ( Video 1 ).

Contrast-enhanced computed tomography reveals a cystic lesion with an enhanced, partially thickened wall (yellow arrowhead) adjacent to the gallbladder.

Endoscopic ultrasound shows a hypoechoic thickened wall in the cystic lesion.

Detective flow imaging shows an irregular vessel in the thickened wall, suggesting a malignant tumor.

A rare gastrointestinal stromal tumor within a hepatic round ligament cyst is diagnosed using detective flow imaging. This novel endoscopic ultrasound technique identifies irregular vessels and guides surgical decision-making.Video 1

During surgery, a cystic tumor was found in the round ligament of the liver. Histopathological examination revealed a cystic tumor with a thickened wall, characterized by sheet-like proliferation of epithelioid cells admixed with spindle-shaped cells, displaying a palisading pattern ( Fig. 4 ). Immunohistochemical staining confirmed the diagnosis of GIST originating from a hepatic round ligament cyst ( Fig. 5 ).

Histopathological examination. a Cystic tumor with a thickened wall (yellow arrowhead). b, c Hematoxylin-eosin: A thickened wall is characterized by sheet-like proliferation of epithelioid cells admixed with spindle-shaped cells, displaying a palisading pattern.

Immunohistochemical staining of the tumor leads to the diagnosis of gastrointestinal stromal tumor. a Positive staining for CD117. b Negative staining for desmin. c Negative staining for S100.

To the best of our knowledge, this is the first reported case using DFI for the evaluation of a GIST arising within a hepatic round ligament cyst. The identification of an irregular vessel on DFI within the tumor can contribute to surgical decision-making in such rare cases.

Endoscopy_UCTN_Code_CCL_1AZ_2AI