Malignant lymphoma is one of the most common malignancies in children, with approximately 60 percent of cases being B-cell, non-hodgkin lymphoma (NHL) . NHL in children progresses rapidly, prone to bone marrow and central nervous system (CNS) involvement , CNS-infested NHL has a poor prognosis regardless of primary or secondary , high-intensity chemotherapy, intravenous rituximab (RTX), radiotherapy, and hematopoietic stem cell transplantation, HSCT) has limited efficacy in the treatment of these children because only a small percentage of drugs/antibodies can penetrate the blood-brain barrier . Only a limited number of intrathecal agents, primarily methotrexate, steroids, and cytarabine, have been identified that have demonstrated safety in the use of CNS-violated NHL but have not improved long-term survival in these children . Therefore, whether safe and effective intrathecal drugs can be found is the focus of the treatment and prevention of CNS-infused NHL.
Most B-cell NHL tumors express CD20 antigen in tumor tissues , RTX is a chimeric monoclonal antibody specific to B-cell CD20 antigen, and a large number of studies have confirmed that intravenous infusion of RTX has a good effect on adult and pediatric B-cell NHL . However, intravenous RTX concentrations in cerebrospinal fluid are low, ranging from 0.1 to 4.4 percent of the blood concentration, and repeated intravenous use does not increase its drug concentration in the cerebrospinal fluid . Recent small clinical studies have shown that intrathecal RTX injection is safe in adult lymphoma patients , but there are no domestic cases of intrathecal RTX use in childhood lymphoma. In this paper, 16 clinical cases of intrathecal RTX injection of stage III and IV. B-cell NHL were analyzed to explore the safety and efficacy of RTX intrathecal therapy.