A PREVIOUSLY healthy 6-year-old boy received lamotrigine after examination for seizures involving the left face and arms. Cranial computed tomography showed a probable brain tumor. Surgery was deferred because of family relocation. On examination 3 months later, he was awake, alert, and had no focal neurological signs. A repeated magnetic resonance imaging study revealed a densely enhancing focal lesion in the right parietal region with mild edema of the underlying white matter (Figure 1). Additionally, he had mild maxillary and ethmoid sinus disease. He underwent a right frontal craniotomy under Stealth guidance. The lesion was partly adherent to the overlying dura mater and was within a portion of the premotor cortex, which was excised. The entire lesion was resected. Biopsy findings revealed a lesion that was well-demarcated from the surrounding brain and consisted of islands and broad zones of reactive, granulation tissue–like whorls of fibrocapillary proliferation with a diffuse infiltrate of lymphocytes, plasma cells, and histiocytes (Figure 2). Plasma cells and histiocytes dominate the inflammatory components. The lesion contained many lipid-rich histiocytes, collagen, and cells that express HLA-DR, CD20, and CD68 (Figure 3). The patient was discharged after surgery with mild residual facial weakness. At last follow-up, he was seizure free.
Lacson A, Washington K, Tuite G, Nuttall R. Pathological Case of the Month. Arch Pediatr Adolesc Med. 2001;155(7):851–852. doi:10.1001/archpedi.155.7.851