Mucosa-associated lymphoid tissue (MALT) lymphoma is very rare in children. We report the first case of pediatric thymic MALT lymphoma in an adolescent Asian girl. She presented with chest pain, dyspnea, and low-grade fever. A large anterior mediastinal mass was biopsied that confirmed the diagnosis of MALT lymphoma with trisomy 18. The patient had secondary immunodeficiency with low NK cell count and high IgA and IgG levels. Because of the advanced stage and the presence of trisomy 18, she was treated with cyclophosphamide, vincristine, prednisone, and rituximab, followed by involved-field radiotherapy. She is currently undergoing maintenance therapy with rituximab and remains in complete remission at 13 months from diagnosis. Thymic MALT lymphoma should be suspected in any Asian child with a cystic thymic mass and autoimmune disease or hyperglobinemia. Because of the slow proliferation rate of this type of lymphoma, a long-term follow-up is needed.
*Department of Paediatrics, Division of Haematology/Oncology
†Department of Paediatric Laboratory Medicine, Division of Pathology
‡Department of Paediatrics, Division of Immunology, The Hospital for Sick Children
§Medical Oncology, Princess Margaret Hospital, Toronto, ON, Canada
The authors declare no conflict of interest.
Reprints: Oussama Abla, MD, Department of Paediatrics, Division of Haematology/Oncology, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, Canada M5G 1X8 (e-mail: firstname.lastname@example.org).
Received July 4, 2011
Accepted November 30, 2011