Histiocytic Sarcoma of the Esophagus

Purpose: Introduction: Histiocytic sarcomas are rare hematolymphoid neoplasms, with frequent extranodal manifestations. Several reports of GI involvement, including the liver, spleen, stomach and colon, have been detailed in the literature. Due to its non-specific morphology, immunophenotypic studies are vital for diagnosis. We present a case of primary esophageal invasion by histiocytic sarcoma, which has not been documented to date. Case: A 46 year old male patient presented with abdominal pain, dysphagia and weight loss over 6 months. Examination revealed epigastric tenderness and non-tender hepatomegaly. Profound leukocytosis was noted, and progressive escalation of all his liver function tests. A CT scan of the abdomen revealed a 6 cm mass at the gastroesophageal junction, multiple hypodense hepatic lesions consistent with metastases and extensive intraabdominal lymphadenopathy. A 10 cm, ulcerative, necrotizing mass just above the gastroesophageal junction was discovered on endoscopy, and biopsy was reported as a histiocytic cell neoplasm. Immunophenotyping revealed positive CD68, Vimentin and EMA. Staining for myeloperoxidase, CD1a, CD30, CD34 and CD117 were absent. Based on these findings, a diagnosis of histiocytic sarcoma was established. Unfortunately, the patient developed intercurrent sepsis with rapid deterioration, dying from multi-organ failure. Discussion: Histiocytic sarcoma is an extremely rare and aggressive malignancy of monocyte/macrophage origin. The median age group affected is the 5th decade, and extranodal presentation is common. Various sites of gastrointestinal involvement have been documented, presenting with hepatosplenomegaly, abdominal pain, intestinal obstruction, bleeding and perforation. This case illustrates a hitherto unreported manifestation, with primary involvement of the esophagus. The diagnostic criteria has been very controversial and recently refined based on immunohistochemical markers. This demonstrates consistent expression of CD68, with CD45 and S100 being equivocal. Markers for myeloid cells (MPO) and Langerhan's cells (CD1a) are conspicuously negative. Resection is favored for localized tumors, and systemic chemotherapy otherwise. Recently, a case treated with stem cell transplantation has been described.Figure: No Caption available.