Littoral Cell Hemangioma of the Spleen.

Introduction: Splenic hemangiomas are rare, range from 0.03–14% in autopsy studies. The primary tumors of the spleen are benign and originate from the vascular endothelium and rarely from the lining cells of red pulp sinuses, giving rise to Littoral cell angiomas (LCA), first described by Falk et al in 1991. It usually is an incidental benign tumor presenting as mild to moderate splenic enlargement seen at any age in both sexes. Grossly it usually has multiple distinct nodules are spongy with dark bloody spaces ranging from 0.2 to 9.0 cm in diameter.

Case Report: 65 years old white male patient presented with thrombocytopenia, platelet count 84000/cmm, Hemoglobin 11.8 and WBC 5500. He had no significant past medical history. Review of systems was noncontributory. There were no other physical findings. The patient had normal upper gastrointestinal series. Colonoscopy revealed tubular adenomatous polyp. CT scan chest revealed thoracic vertebral hemangioma. CT scan of abdomen showed enlarged spleen measuring 15cm axially with multiple low attenuation areas throughout the spleen. FNA of spleen showed spindle cells positive for factor VIII and CD31. The patient had normal bone marrow biopsy as well as cytogenetics. The patient underwent splenectomy which showed littoral cell angioma with heterogeneous population of lymphocytes, histiocytes, eosinophila, neutrophils, platelets, and large polylobated cells. The patient had marked clinical improvement with normallization of platelet count post splenectomy.

Discussion: Littoral cell angiomas are seen as hypo echoic areas seen on ultrasonography and CT scan of abdomen. The natural history is benign and do not recur post splenectomy. Spontaneous rupture can occur in 25% of patients. On MRI, siderosis is seen due to hemophagocytosis by littoral cells. The lesions are of variable size and solitary or multinodular located in the red-pulp of the spleen. They are composed of anastomosing vascular channels with irregular lumina featuring cyst-like spaces. The LCA cells have a dual-endothelial/histiocytic characteristics, that react with F VIII Ag and are positive for CD68 antigen. Angiostatin inhibits angiogenesis and metastatic tumor growth. The mildly atypical cells, but not frankly malignant with low Ki 67 staining and diploid DNA histogram are in accordance with a low-grade malignancy. LCA has also been associated with synchronous malignancies such as lymphoma, colonic cancer, renal cancer, ovarian cancer, pancreatic cancer, seminoma and gastric leiomyosarcoma, a long-term follow-up for these patients is recommended.