3.4 Treatments and outcomes of patients with HLH
Two patients with primary HLH were treated according to the HLH-2004 protocol, which includes etoposide, dexamethasone, and cyclosporine.4 Among patients with IAHS, intravenous immunoglobulin (IVIg) was the most frequently used treatment, administered to 77% of all patients in this category. Dexamethasone followed at 65%, while etoposide and cyclosporine were used in half of these patients. For patients with MAHS, a chemotherapy regimen based on the underlying disease was provided most frequently, used in 62% of cases in this subgroup. In contrast, patients with MAS-HLH predominantly received methylprednisolone, administered to 79% of these patients, and none were treated with etoposide. No patients from this cohort underwent allogeneic hematopoietic cell transplantation. Only 2 patients received salvage treatment with ruxolitinib, one with primary HLH and the other with subcutaneous panniculitis-like T-cell lymphoma (SPTCL).
In this cohort, 54 out of 86 patients with HLH (62.8%) were still alive at a median follow-up of 9.8 months (IQR: 0.8–37.7 months). The Kaplan-Meier survival analysis indicated that the 2-year and 5-year OS rates were 61.9% and 55.9%, respectively (Fig. 2A).
The OS rates of patients with and without R/R HLH were compared. Patients with R/R HLH, at a median follow-up of 0.9 months (IQR: 0.4 – 9.7 months), had 2-year and 5-year OS rates of 13.5% and 9.0%, respectively. Conversely, patients without R/R HLH, at a median follow-up of 23 months (IQR: 3.1 – 45.6 months), experienced 2-year and 5-year OS rates of 90.5% and 87.2%, respectively. This marked difference in OS between the two groups was statistically significant (p < 0.001), as illustrated in Fig. 2B.