Humans ; Clinical Relevance ; Receptor, trkA/genetics* ; Neoplasms ; Digestive System Neoplasms/genetics* ; Oncogene Proteins, Fusion/genetics* ; Gene Fusion

Humans ; Thyroid Cancer, Papillary ; Neck/pathology* ; Lymph Nodes/pathology* ; Thyroid Neoplasms/pathology* ; Lymphoma, T-Cell/pathology*

Objective: To investigate the clinicopathological characteristics of malignant gastrointestinal neuroectodermal tumors (GNET), and to describe their clinical, histological, immunophenotypic, ultrastructural, and molecular features, diagnosis and differential diagnosis. Methods: Three cases of malignant GNET were collected at Xijing Hospital of the Fourth Military Medical University, from 2013 to 2022. All patients underwent surgical resection of the tumor. Histological, immunohistochemical (IHC), ultrastructural and molecular genetic analyses were performed, and the patients were followed up for six months, three years and five years. Results: There were two males and one female patients. The tumors were located in the ileum, descending colon, and rectum, respectively. Grossly, the tumors were solid, firm, and poorly circumscribed, measured in size from 2 to 4 cm in greatest dimension, and had a greyish-white cut surface. These tumors were histologically characterized by a sheet-like or nested population of oval to spindled cells or epithelioid cells with weakly eosinophilic or clear cytoplasm, small nucleoli and scattered mitoses. Electron microscopy showed neuroendocrine differentiation, and no evidence of melanogenesis. IHC staining showed that the tumor cells were diffusely positive for S-100 protein, SOX10, CD56, synaptophysin and vimentin. They were negative for melanocytic markers, HMB45 and Melan A. All three cases showed split EWSR1 signals consistent with a chromosomal translocation involving EWSR1. Next-generation sequencing in one case confirmed the presence of EWSR1-ATF1 fusion. These patients were followed up for 6 months, 3 years and 5 years, respectively, and all of them developed possible lung or liver metastases, and one of them died of multiple pulmonary metastases. Conclusion: Malignant GNET has distinctive morphological, IHC, and molecular genetic features and it should be differentiated from other malignancies of the gastrointestinal tract, especially clear cell sarcoma and melanoma.
Male ; Humans ; Female ; Biomarkers, Tumor/analysis* ; Gastrointestinal Neoplasms/pathology* ; S100 Proteins/analysis* ; Melanoma

Objective: To investigate the clinical manifestations, histomorphology, and differential diagnosis of primary hepatic angiosarcoma. Methods: Nine cases of primary hepatic angiosarcoma diagnosed in the Department of Pathology, the First Affiliated Hospital of Nanjing Medical University from January 2014 to December 2021 were collected, including biopsy and surgical specimens. The histomorphology, clinical, and radiologic findings were analyzed. The relevant literature was also reviewed. Results: There were six males and three females, aged 30 to 73 years (mean 57 years). Grossly, the growth pattern of the tumor was classified as either mass formation or non-mass formation (sinusoidal). Microscopically, the mass-forming primary hepatic angiosarcoma were further subdivided into vasoformative or non-vasoformative growth patterns; and those non-vasoformative tumors had either epithelioid, spindled, or undifferentiated sarcomatoid features. Sinusoidal primary hepatic angiosarcoma on the other hand presented with markedly dilated and congested blood vessels of varying sizes, with mild to moderately atypical endothelial cells. Follow-up in all nine cases revealed 8 mortality ranging from 1 to 18 months (mean 5 months) from initial diagnosis. One patient was alive with disease within a period of 48 months. Conclusions: Primary hepatic angiosarcoma is a rare entity with a wide spectrum of histomorphology, and often misdiagnosed. It should be considered when there are dilated and congested sinusoids, with overt nuclear atypia. The overall biological behavior is aggressive, and the prognosis is worse.
Male ; Female ; Humans ; Hemangiosarcoma/diagnosis* ; Endothelial Cells/pathology* ; Liver Neoplasms/surgery* ; Prognosis ; Biopsy