Primary Burkittʼs Lymphoma of the Appendix Presenting as Acute Appendicitis

Abstract

Purpose: Primary malignant small-bowel neoplasms are rare, constituting about 2% of primary gastrointestinal malignancies. Primary appendiceal lymphomas constitute only about 0.015% of all GI lymphomas. Burkitt's lymphoma of the appendix has been reported to occur in children. We present an index case of Burkitt's lymphoma of the appendix in an adult male who presented with acute appendicitis. Methods: A 60 year old Caucasian male presented with one day history of right lower quadrant pain and nausea. Physical exam was unremarkable except for localized tenderness over the right lower quadrant. Laboratory exam was unrevealing. CT scan of the abdomen showed a 6.5 × 4.5 cm retroperitoneal enhancement that was consistent with appendicitis with no organomegaly. Emergent surgical exploration revealed a ruptured appendix with minimal peritonitis. The appendix appeared highly vascular and edematous but was not typical of acute inflammatory appendicitis. Histopathological analysis of the appendix revealed high grade lymphoma with serosal involvement. Tumor cells expressed a high mitotic rate with numerous tingible body macrophages creating the starry sky pattern, highly suggestive of Burkitt's lymphoma. Cytogenetic analysis for [t (8,14)], IgH/c-myc translocation, FISH for c-myc rearrangement and PCR for IgH/JH gene rearrangement were positive. Immunophenotyping revealed CD20 and CD10 positive cells which are specific for the diagnosis. Patient underwent staging workup and was found to have localized stage 1E Burkitt's lymphoma. He was initated on aggressive chemotherapy with three cycles of (cyclophosphamide, vincristine, doxorubicin, high-dose metho-trexate, and intrathecal therapy). Conclusions: Malignant small-intestine lymphoma has an estimated annual incidence of 0.12 per 100,000 persons, and represents approximately 20% of primary malignancies of the small intestine. Histopathological characteristics include the tangible macrophages and the starry sky pattern. C-myc/IgH translocation has a specificity of 80% for the diagnosis. A high index of suspicion and meticulous histopathological examination were vital in diagnosis and therapy of this rare and aggressive tumor. [figure 1]Figure