Clinical Features, Treatment, and Outcomes of Nivolumab-Induced Hemophagocytic Lymphohistiocytosis.

Haemophagocytic lymphohistiocytosis (HLH) is a rare and fatal immune-related event of nivolumab. The clinical features of nivolumab-induced HLH are unclear. The aim of this study was to investigate the clinical features, treatment, and outcome of nivolumab-induced HLH to provide information for prevention and treatment. We collected nivolumab-induced HLH-related case reports for retrospective analysis by searching the Chinese and English databases from inception to March 31, 2024. HLH developed in 24 patients, with a median age of 57 years (range: 26, 86). The onset of HLH symptoms ranged from 3 days to 68 weeks after administration, with a median time of 5.5 weeks. Fever (87.5%) was the most common symptom and could be accompanied by splenomegaly (66.7%) and hepatomegaly (20.8%). Laboratory tests revealed hemocytopenia, hypertriglyceridemia, hypofibrinogenemia, hyperferritinemia, increased sCD25, and decreased natural killer cell activity. Bone marrow biopsy showed hemophagocytosis (62.5%). After discontinuing nivolumab, HLH patients receiving systemic steroids, tocilizumab, and anakinra showed positive results. As a rare adverse reaction of nivolumab, HLH requires rapid diagnosis and appropriate treatment based on clinical symptoms and laboratory tests. Tocilizumab and anakinra can be used as an effective treatment against the steroid HLH.