Severe hemophagocytic lymphohistiocytosis in a melanoma patient treated with ipilimumab + nivolumab.

BACKGROUND: Treatment of metastatic melanoma patients with immune checkpoint inhibitors is an important standard of care. Side effects are due to immune activation, can affect virtually all organ systems, and are occasionally severe. Although hematologic toxicity has been reported, we present a case of hemophagocytic lymphohistiocytosis (HLH) due to immune checkpoint inhibitor therapy. CASE PRESENTATION: A patient with metastatic melanoma was treated with one course of ipilimumab + nivolumab and presented 3 weeks later with severe anemia and hyperferritinemia. A bone marrow biopsy revealed necrotic tumor cells, infiltrating T cells, and hemophagocytosis. The patient was treated with high-dose steroids; 12 months later, the patient remains off all therapy and in complete remission of both HLH and metastatic melanoma. CONCLUSIONS: The hemophagocytic syndromes are attributable to dysregulated immune activation and share pathophysiologic mechanisms with immune activation from checkpoint inhibitors. Increasing use of regimens that include immune checkpoint inhibition require vigilant monitoring for immune-activating side effects as they can occasionally be life threatening, as in this case of HLH.

Fifty years of hairy cell leukemia treatments.

Treatment of hairy cell leukemia (HCL), a disease first described in 1958, has evolved from splenectomy, which resulted in a normalization of blood counts in about 41% of patients and an improvement in the remaining 59% of patients but with a time to failure of only approximately 19 months, through treatment in the early 1980s with interferon, which resulted in the same high overall response rate but with a time to failure of approximately 31 months. Subsequently, therapy with either pentostatin or cladribine showed an increase in the complete remission (CR) rate to approximately 80-90%, with only a small percentage of patients relapsing at approximately 30 months. More recently, patients who have failed either or both of these drugs have been shown to respond to rituximab or the experimental drug, BL22 (HA22). With these documented successes, the outlook for patients diagnosed with HCL, 50 years after the disease was first described, is so positive that patients with HCL have survival curves similar to those for the appropriate age-related cohorts.