2613 A Rare Case of Undifferentiated Malignant Epithelioid Neoplasm

Abstract

INTRODUCTION: The small bowel is rarely a site for development of tumor malignancy and accounts for less than 1% of all GI malignancies. We present a case of a 53-year-old male with recurrent episodes of gastrointestinal bleeding and negative upper and lower GI endoscopies found to have high-grade undifferentiated high-grade malignant epithelioid neoplasm. CASE DESCRIPTION/METHODS: A 53-year old male with history of peptic ulcer disease, duodenal ulcer perforation presented to the ED with right upper and lower extremity pain for last few weeks along with black stools. He had required several units of blood transfusion with recurrent admissions to hospital and had also lost about 20 lbs in last 2 months. EGD and colonoscopy 3 months before had shown duodenal angiectasia and colonic polyps which were removed. Outpatient capsule endoscopy was recommended but patient did not follow up. Bleeding scan was negative and CT abdomen pelvis with contrast showed thickening in distal jejunum concerning for mass-like lesion. Patient underwent laparoscopic small bowel resection of 18 cm and pathology showed high-grade undifferentiated malignant epithelioid neoplasm with macro-metastatic tumor. The tumor showed diffuse staining for vimentin,pancytokeratin, CK7 with subset moderate cytoplasmic staining for calretinin and CK8/18.Port-A-Cath was placed and patient was started on standard adjuvant chemotherapy including combination of 5-FU, leucovorin, and oxaliplatin. DISCUSSION: Small bowel tumors are very rare and aggressive and have poorer prognosis than colon cancer. They present a diagnostic challenge as access to small bowel is limited during conventional diagnostic procedures and symptoms present late. We present a patient who was having recurrent gastrointestinal bleeding requiring multiple blood transfusions and found to have high-grade undifferentiated high-grade malignant epithelioid neoplasm. The differential for this includes monophonic synovial sarcoma, malignant epithelioid mesothelioma, and large cell lung carcinoma vs others. Video capsule endoscopy has rapidly become the conventional standard for small bowel evaluation, followed by other methods such as magnetic resonance enteroclysis. Standard chemotherapy treatment closely resembles that of large bowel cancer, including combinations of 5-FU, leucovorin, and oxaliplatin/irinotecan/capecitabine.