Introduction Venetoclax is utilized with low-dose cytarabine or a hypomethylating agent for the treatment of acute myeloid leukemia. Clinical trials report a risk of tumor lysis syndrome and the package insert recommends a venetoclax dose ramp-up at the initiation. The purpose of this study was to evaluate the risk of tumor lysis syndrome in a large population of patients with acute myeloid leukemia outside of a clinical trial and evaluate the incidence of hospital-acquired complications during inpatient ramp-up. Methods We performed a retrospective study of adult patients with acute myeloid leukemia receiving venetoclax with a hypomethylating agent or low-dose cytarabine. The primary outcome was the incidence of tumor lysis syndrome. Secondary outcomes included risk factors for tumor lysis syndrome, length of admission, and incidence of hospital-acquired complications. Results One hundred thirteen patients were included. Although all patients were given some form of prophylaxis, the incidence of tumor lysis syndrome was 8.8%. All were laboratory tumor lysis syndrome; one with hyperuricemia, nine with hypocalcemia, and ten with hyperphosphatemia. Six patients received sevelamer. Tumor lysis syndrome was resolved in all cases. No clinical tumor lysis syndrome occurred. Hepatic dysfunction, tumor lysis syndrome high-risk stratification, higher baseline white blood cell count, and lactate dehydrogenase levels were more common in the tumor lysis syndrome group. Hospital-acquired complications reached 13% in those directly admitted for dose ramp-up. Conclusions Tumor lysis syndrome was uncommon and manifested as minor lab abnormalities. White blood cell count continues to be an indicator of risk for tumor lysis syndrome. Those who present with an elevated white blood cell or are otherwise at high risk for tumor lysis syndrome should be admitted for ramp-up. Otherwise, initiation and monitoring of venetoclax are feasible in the outpatient setting.
