Ruxolitinib Monotherapy for a Child With HAVCR2 Gene Mutation Associated Subcutaneous Panniculitis-Like T-Cell Lymphoma: A Case Report.

BACKGROUND:The occurrence of hemophagocytic lymphohistiocytosis (HLH) in patients with subcutaneous panniculitis-like T-cell lymphoma (SPTCL) may be due to HAVCR2 gene mutation, leading to T-cell immunoglobulin and mucin domain-containing molecule 3 deficiency, T-cell and macrophage activation, and proinflammatory cytokine production. OBSERVATION:We report a patient with SPTCL and HLH for whom ruxolitinib, used as a novel treatment, showed notable therapeutic effects. CONCLUSIONS:Remission of both HAVCR2 mutation-induced high inflammatory characteristics and significant symptoms post-ruxolitinib administration suggested that patients with SPTCL and HLH may not represent typical lymphoma cases. Ruxolitinib, with its relatively low toxic side effects, can provide favorable outcomes.