Tumor lysis syndrome in a chronic lymphocytic leukemia patient with pleural effusion after oral fludarabine and cyclophosphamide therapy.

Tumor lysis syndrome (TLS) is a rare complication of the treatment for chronic lymphocytic leukemia (CLL). Since the advent of new therapeutic agents with higher response rates, however, TLS has been observed with increasing frequency. An 84-year-old woman with a nine-year history of untreated CLL presented with exacerbating dyspnea due to pleural effusion.