Objective To evaluate the imaging features of hepatic epithelioid hemangioendothelioma (HEHE). Methods The imaging data of 15 patients with HEHE proved by surgery and pathology who reeived treatment in West China Hospital from Jul. 2012 to Aug. 2018, were retrospectively analyzed. The location, boundary, density/signal, and enhanced features of tumor were observed. Results Among 15 cases, there were 3 cases of single, 5 cases of multiple, and 6 cases of fusion. Thirteen cases were distributed under the capsular of liver, accompanied by the capsule retraction sign, 14 cases had lollipop sign, 7 cases had core pattern sign. On plain CT images, the lesions manifested as low density. On plain MR images, the lesions had hypointense on T1-weighted images and hyperintense on T2-weighted images. The enhanced scanning could be characterized by mild enhancement, rim-like enhancement at early phase, and progressive centripetal fill-in enhancement during dynamic phase imaging. Conclusions CT and MRI imagings of HEHE are different, and there are certain characteristics of capsule retraction sign, lollipop sign, and core pattern sign.
ObjectiveTo summarize the clinicopathological features of microencapsulated/reticular schwannoma.MethodsTwo cases of microencapsulated/reticular schwannoma treated in West China Hospital of Sichuan University were retrospectively collected. The histological and immunohistochemical features were summarized, and the related literatures were reviewed.ResultsTwo cases of microcystic/reticular neurilemmoma diagnosed and treated in West China Hospital of Sichuan University were male. The clinical manifestations were “dull pain in the right lower abdomen” and “mass of left index finger”. Microscopically, the characteristic reticular or cribriform structures were found in all cases, and lymphocytic sheath was seen in 1 case. Immunohistochemical staining showed S-100, glial fibrillary acidic protein (GFAP) and calretinin positive. By February 2020, only 41 cases were reported in the literatures （there were no cases of this group),there was no significant gender difference, the median age was 55 years (11–93 years), and the median size of the lesion was 2.1 cm (0.4–13.0 cm). Most of them were found by accident, without obvious symptoms and signs, and no history of neurofibromatosis type 1 or 2. Microencapsulated/reticular schwannoma in this patients mainly occurs in the viscera, especially in the gastrointestinal tract (mostly in the the colorectal of lower gastrointestinal tract ), most of them were solitary nodular masses without capsule. Microscopically, the boundary was clear, and the characteristic microcapsules and reticular structures were seen. The tumor cells were diffusely expressing S-100 protein, and GFAP and calretinin were expressed in varying degrees. Electron microscopy showed the characteristics of Schwann cells.ConclusionsMicrocystic/reticular schwannoma is a rare subtype of schwannoma, which needs to be differ-entiated from multiple benign and malignant neoplasms. The diagnosis of the tumor is a challenge for the pathologist.