Marginal Zone Lymphoma (MZL) is a type of non-Hodgkin lymphoma (NHL) originating from B-lymphocytes. It is characterized as a slow-growing or indolent lymphoma and is considered a rare disease. The report focuses on a case of MZL diagnosed in childhood, which relapsed after initial treatment and subsequently went into remission following ibrutinib-obinutuzumab treatment.

In 2010, a 9-year-old girl with no previously known systemic illnesses was diagnosed with stage 4B nodal marginal zone lymphoma outside a pediatric center. Initially, she achieved remission following treatment with rituximab-bendamustine but experienced a relapse in 2012. Subsequent to lymph node excision and Methotrexate, Ifosfamide, Etoposide, and Dexamethasone (MIED) therapy, all conducted outside the pediatric center, she received an autologous stem cell transplant in 2013.

Five years after the transplantation, she applied to our center when she was 18 years old, exhibiting widespread lymphadenopathy and suffering a relapse of stage 4B nodal MZL. Treatment with ibrutinib-obinutuzumab was commenced, leading to a full response after six cycles, without any adverse effects. Maintenance therapy with ibrutinib was initiated to avert further recurrence.

The treatment of relapsed nodal MZL continues to be challenging. In patients who have previously received repeated cytotoxic chemotherapy, the combination of ibrutinib-obinutuzumab may be an effective and safe option to avoid cumulative toxicity of chemotherapy. Further studies with more cases in R/R nodal MZL will contribute to the management of the disease.