Secondary H3K27 Altered Diffuse Midline Glioma in a Treated Case of Acute Lymphoblastic Leukemia: A Case Report

Case Reportwhich was insidious in onset and gradually progressive in nature.Clinical examination was unremarkable for any focal neurological deficit and higher mental functions were normal.He had past history of Philadelphia negative B-ALL in 2018 at the age of 21 years.He was treated with MCP 841 protocol consisting of multiagent chemotherapeutic agents like anthracyclines, antimetabolites, alkylating agents and steroid divided in phases like induction phase 1 and 2 which included PCI, reinduction, consolidation and maintenance.PCI was delivered with conventional 2D technique with a dose of 1800 cGy/10 fractions which was completed in 2018.Maintenance phase comprising 18 months of chemotherapy was completed in 2021 and was kept under observation thereafter.Magnetic Resonance Imaging (MRI) Brain with MR Spectroscopy (MRS) and whole spine screening was done revealing multiple thick walled cavitary lesions in right posterior capsuloganglionicthalamus and centrum semiovale region measuring 3.6x3.8x3.7 cm with 2 adjacent small nodular hyperintense lesions in right parietal white matter measuring 1.4x2.4cm and part of subependymal periventricular region aspect of trigone of right lateral ventricle measuring 1.2x1.4cm which were hyperintense on T2W, hypointense on T1W and FLAIR (Fluid Attenuated Inversion Recovery) images and MRS showing raised choline peak and reduced N Acetyl Aspartate (NAA) suggestive of glioma (Figure 1).After ruling out leukemic relapse by doing CSF microscopic and biochemical examination, cytology, flow cytometry which were unremarkable, investigations to rule out infective etiology by CSF culture for bacterial, fungal infection and Cartridge-based nucleic acid amplification SummaryH3K27 altered diffuse midline glioma is a distinct grade IV glioma as per the recent 2021 WHO classification of primary CNS tumors.Herein, we report a rare case of a 26-year-old male diagnosed with this after treatment of B cell Acute Lymphoblastic Leukemia (B-ALL) with a latency period of 5 years post cranial radiation therapy (PCI).A 26-year-old male presented to the Medical Oncology Department with complaints of tingling sensation in bilateral upper limb for 15 days.MRI brain with MR Spectroscopy and whole spine screening revealed multiple thick walled cavitary lesions in right posterior capsuloganglionicthalamus and centrum semiovale region.He had a past history of treatment of Philadelphia negative B-ALL in 2018 at the age of 21 years with MCP 841 protocol.Near total resection (NTR) of brain lesion was done and histopathology revealed this diagnosis.He is planned for adjuvant radiation with temozolomide.