Lesions of the Central Nervous System in Leukemia: Pathologic and Magnetic Resonance Imaging (MRI) Features in 14 Patients
Authors: Liu Jing , Wang Yaming , Sun Xuefei , Qian Jun , Liu Shuo , Yu Zhenkun , Ji Nan , Sun Shengjun , Liu Yuanbo 
Published: October 2019

Abstract
Lesions of the central nervous system (CNS) were seen during and after treatment of leukemia. We aimed to characterize the specific pathology and MRI findings observed in leukemia patients with CNS lesions and to determine their value in the management of such patients. The data from stereotactic biopsy for pathology (12 patients) and MRI examinations (14 patients) were retrospectively evaluated. Factors that predisposed to the lesions of CNS were reviewed from the medical records. Among the 14 patients, 4 had a CNS infection, 2 had a neurodegenerative disorder, 8 had CNS leukemia. The clinical diagnosis based on clinical presentation and MRI features was not consistent with the pathological diagnosis in 2 patients: in one patient, the clinical diagnosis was a CNS infection, though the patient's pathological diagnosis was CNS leukemia; in the other patient, the clinical diagnosis was CNS leukemia, but the pathological diagnosis was glial cell hyperplasia. CNS lesions in leukemia have a wide range of causes. Apart from the relapse of leukemia in CNS, there are treatment related neurotoxicities and infections that are caused by immunocompromised states. Stereotactic biopsy for pathological confirmation has the advantages of minimal invasion and convenience, which remains the gold standard for diagnosing the nature of CNS lesions. Because many CNS lesions of leukemia are treatable, early correctly diagnosis is essential.
Table 1. Medical records of 14 leukemia patients with CNS lesions case Age, y /Sex Leukemia type A/I* Clinical presentation MRI findings clinical diagnosis Stereotactic biopsy for pathology diagnosis Outcome 1 15/M AML (M5) 14/3 d after Cyclosporin Seizure MRI: The left occipital lobe, right frontal lobe low-density lesions with enhancement of capsule wall. Infection Fungal brain abscesses Improved 2 38/M AML 34/9 mo after allo-HSCT Fever MRI: Scattered lesions at the right frontal lobe. Short T1, long T2 signal. Infection Not performed Improved 3 20/M ALL 20/during 2nd course of chemo Headache, limb tic MRI: Bilateral cerebral hemisphere cortex multiple long T1 and T2 signal nodular lesions. Infection Fungal brain abscesses Improved 4 54/M APL 53/2 mo after Retinoic acid Headache, limb numb, seizure MRI: Bilateral posterior parietal lobe showing patchy enhancement. Leukemia Leukemia Improved 5 7/M ALL (B cell) 7/during the chemo Headache MRI: a cystic lesion in the right temporal lobe and cerebellum obvious edema. Infection Leukemia Progressed 6 26/F AML (M4) 25/during 4th course of chemo Fever, tic MRI: Mixed signals at the left frontotemporal top border zone. Infection Brain abscesses Improved 7 25/M ALL (T cell) 21/3 y after immuno-suppressive agent Headache, limb weakness MRI: Mixed signals at right hemisphere, perilesional mild enhancement. Leukemia T cell leukemia/lymphoma Improved 8 16/M ALL (T cell) 16/ at the diagnosis of leukemia Headache, blurred vision MRI: Scattered, abnormal signal of sizes at the cerebellum. Leukemia Not performed Progressed 9 49/M ALL (B cell) 49/1 mo after chemo none MRI: Glial cell proliferation around lesion at right parietal lobe. Leukemia Glial cell hyperplasia Improved 10 60/M CMML 57/4 y after allo-HSCT Nausea, right limb weakness MRI: a 2.5×2 cm2 lesion in left basal ganglia. Leukemia Chronic myelomonocytic leukemia Died 11 26/M ALL (B cell) 20/9 mo after last course of chemo Headache MRI: lesions at the left temporal lobe, perilesional with obvious edema. Leukemia B cell leukemia/lymphoma Improved 12 29/F AML (M5b) 27/1 mo after last course of chemo none MRI: Bilateral cerebellum, left occipital lobe abnormal signal enhanced on T1 with Gd. Leukemia Leukemia Improved 13 42/M ALL 41/3 mo after allo-HSCT Dizziness, Walking instability MRI: The left cerebellar hemisphere visible nodular enhancement lesions. Leukemia Leukemia Improved 14 23/F ALL (B cell) 23/1 mo after allo-ASCT headache MRI: The right paracele white matter lesions visible long T1, long T2 signal, the boundary is not clear, edema is not obvious, no enhancemen. Degenerative disease Nerve cell degeneration Improved *A, the age when the diagnosis was made for leukemia.I, the interval between the last treatment and the onset of neurological symptoms.
Figure 1. The MRI, biopsy site and pathology of a 60-year-old man with CMML Figure 1. The MRI, biopsy site and pathology of a 60-year-old man with CMML Figure 2. The MRI, biopsy site and pathology of a 23-year-old woman with ALL Figure 2. The MRI, biopsy site and pathology of a 23-year-old woman with ALL Figure 3. The MRI, biopsy material and pathology of a 15-year-old man with AML (M5) Figure 3. The MRI, biopsy material and pathology of a 15-year-old man with AML (M5)

Disclosures
No relevant conflicts of interest to declare.