Spontaneous Tumor Lysis Syndrome Secondary to Appendiceal Burkitt Lymphoma in an Older Man With Ascites

Malignant ascites is the accumulation of fluid-containing malignant cells in the peritoneal cavity, most often due to solid organ tumors. Rarely, abdominal lymphoma may also cause malignant ascites and masquerade as a colorectal tumor on imaging. Early diagnosis of aggressive lymphomas is important due to their potential for oncologic emergencies, including tumor lysis syndrome. Therefore, it is critical that lymphoma remain on the differential diagnosis for malignant ascites until it is ruled out. Here, we present a case of appendiceal Burkitt lymphoma presenting as rapid onset ascites and spontaneous tumor lysis syndrome.