Primary Central Nervous System Lymphoma Masquerading as Brain Metastasis

IN A 41-year-old woman with no prior medical illness presented with a 1-month history of slurred speech and left hemiparesis. In addition, she had been experiencing progressive dysphagia for the past 2 weeks. Upon arrival at the hospital, her Glasgow Coma Scale score was E4 (blank stare), V1, and M5. Blood investigations were within normal limits, and HIV test was nonreactive. A contrast-enhanced computed tomography (CT) brain scan showed multiple enhanced lesions in the right frontal lobe and basal ganglia, suggesting metastasis [Figure 1]. A CT scan of the thorax, abdomen, and pelvis was performed, but no primary lesion was identified. A positron emission tomography scan was not performed because it was not available at our facility. To establish a definitive diagnosis, a burr hole and biopsy were performed. The histopathological examination of the biopsy sample indicated non-Hodgkin lymphoma with a B-cell phenotype (positive for CD10, CD20, and BCL-6 on immunohistochemical staining). Based on these findings, the patient was diagnosed with primary central nervous system lymphoma (PCNSL). Following the diagnosis, the patient’s condition further deteriorated while in the ward despite being on steroids. The health-care team offered the patient chemotherapy and radiotherapy as treatment options. Unfortunately, the family expressed reluctance to pursue aggressive treatment, and as a result, the patient was offered palliative care focusing on symptom relief.Figure 1: A contrast-enhanced computed tomography brain scan showing multiple enhanced lesions in the right frontal lobe and basal gangliaPCNSL is a rare type of extra-nodal B-cell non-Hodgkin lymphoma with a focus located in the brain, leptomeninges, spinal cord, or eyes. It is an extremely aggressive disease that carries a poor prognosis, with a 5-year survival rate of 30.1%.[1] HIV infection is associated with an increased risk of B-cell lymphoma, and life-threatening complications have previously been reported.[2-4] A large proportion, up to 80%, of patients with PCNSL experience focal neurological deficits, with the symptoms often corresponding to the location of the lesion within the central nervous system. The most common clinical manifestation is cognitive impairment, which is frequently accompanied by difficulties in thinking, memory loss, confusion, and changes in behavior. Gait disturbances, such as problems with balance and coordination, are also commonly observed.[5] On brain imaging, the most common locations of PCNSL are periventricular white matter, basal ganglia, and corpus callosum; single lesions account for 70% of cases and multiple lesions account for 30% of cases.[6] Treatment options for PCNSL typically involve chemotherapy, radiation therapy, or a combination of both.[7] However, in this particular case, the patient’s family opted for palliative care, focusing on managing symptoms, and providing comfort during the end-of-life phase. Conflicts of interest There are no conflicts of interest. Declaration of patient consent The authors certify that he has obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published, and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Funding Nil. Author’s contribution Nil.