Hypothalamic obesity syndrome: rare presentation of CNS+ B-cell lymphoblastic lymphoma

Abstract

Hypothalamic obesity syndrome can affect brain tumor patients following surgical intervention and irradiation. This syndrome is rare at diagnosis in childhood cancer, but has been reported with relapse of acute lymphoblastic leukemia. Here we present a case of hypothalamic obesity syndrome as the primary presentation of a toddler found to have CNS+ B-cell lymphoblastic lymphoma. Cytogenetic studies on diagnostic cerebrospinal fluid revealed MLL gene rearrangement (11q23). Hyperphagia and obesity dramatically improved following induction and consolidation chemotherapy. We describe a novel presentation of hypothalamic obesity syndrome in CNS B-cell lymphoblastic lymphoma, responsive to chemotherapy.

Fig. 1

Brain MRI T1 axial image demonstrating diffuse leptomeningeal enhancement and right nodular occipital lesion (arrow) prompting initial referral (A). T1 axial image highlighting enhancement of cranial nerves (B). Spine MRI sagittal section (C) demonstrating leptomeningeal enhancement along spinal cord (arrow). CT abdomen coronal image (D) of left kidney hypodense lesions (arrow).

Fig. 2

Malignant lymphoblasts on initial diagnostic lumbar puncture cytology (A). Change in weight and BSA between 18 months prior to diagnosis and through 9 months of A5971-B1 therapy (B). Rapid resolution of hypothalamic obesity noted following induction therapy. Start of each phase of therapy is indicated by arrowheads (IND, induction; C, consolidation; IM, interim maintenance; DI, delayed intensification; M, maintenance; PRT, proton radiation therapy).