Case Report of Primary Lymphoma of the Central Nervous System in an Immunocompetent 10-Year Old Boy

Primary central nervous system lymphoma (PCNSL) is a very rare and aggressive form of B-cell non- Hodgkin’s lymphoma. It originates but is restricted to the central nervous system (CNS) at the time of diagnosis. Patients typically present with focal neurologic deficits, cranial neuropathies and features of raised intracranial pressure (RICP). Systemic involvement is uncommon in documented cases of PCNSL.

We report a 10-year-old boy who presented with a headache, neck pain and early morning projectile vomiting of eight weeks duration. He developed abnormal behaviours, gait and visual disturbance and lapsed into unconsciousness two days before presentation. He had cranial neuropathies, dilated pupils, papilloedema but had no lymphadenopathy, systemic involvement and no meningeal irritation. There was no background immunosuppression. A diagnosis of suspected cerebral astrocytoma with RICP was made. CNS tuberculosis was also considered. The computerised tomography scan showed multiple homogenous contrast-enhancing lesions with mild peri-lesional oedema in the frontal lobes, left thalamus with effacement of the sulci and Sylvian fissures. All the ventricles appeared normal. He had leucocytosis of 31.9 x 103/uL with neutrophilia. Cerebrospinal fluid analysis revealed elevated protein and lymphocytic infiltrate. Screening for tuberculosis and human immunodeficiency virus (HIV) were negative. A definitive diagnosis of PCNSL was then made. He had intra-thecal steroids and chemotherapy before he succumbed to the illness. Histology at autopsy confirmed the diagnosis of PCNSL. Though rare in children, PCNSL should be considered in any child who presents with features of characteristic mass lesions in the brain with RICP.