A 47-year-old man with no significant past medical history presented to the University of Louisville Hospital with complaints of 5 days of nausea and vomiting, diffuse abdominal pain for the past 5 months, as well as a 50 pound weight loss over this same time period. Physical examination revealed an afebrile white male in no distress. Abdominal examination revealed a soft, nondistended abdomen with hypoactive bowel sounds and tenderness to palpation in the left upper and right lower quadrants. The laboratory results revealed a mild leukocytosis with WBC = 13.4 (granulocytes = 85%) and no other significant abnormalities. The patient was taken to the operating room for exploratory laparotomy where he was found to have a ruptured appendix, an edematous, inflamed gallbladder, and a large splenic mass. The patient underwent an appendectomy, cholecystectomy, and splenectomy.
Pathologic Findings On gross examination, the 510 g spleen measured 17.5 × 10.0 × 7.0 cm and displayed a smooth, dark pink surface with an intact capsule. On cut surface, a well circumscribed 9.0 × 9.0 × 8.0 cm lobulated brown lesion was seen in the lateral spleen occupying greater than half of the organ. Microscopically, the tumor was composed of endothelial cells having abundant, eosinophilic, vacuolated cytoplasm and intracellular vascular lumina Immunohistochemical studies performed on formalin-fixed, paraffin-embedded tissue revealed that the neoplastic endothelial cells expressed CD31, CD34, and thrombomodulin, but were negative for low and high molecular weight cytokeratins (AE1/AE3) and human herpesvirus-8. Discussion: Hemangioendothelioma is a vascular tumor of endothelial cells that is intermediate between benign hemangiomas and frankly malignant angiosarcomas. The epithelioid variant displays endothelial cells with considerable eosinophilic, often vacuolated, cytoplasm. Vascular lumina are evident, and there is a paucity of mitoses. These tumors occur in almost all locations. Surgical removal is generally curative, but about 1/5 of the patients develop metastases.