MRI Features and Misdiagnosis of Primary Central Nervous System Lym-phoma

QUAN Jianhua; LIU Chong

doi:10.3969/j.issn.1002-3429.2024.13.003

Abstract：Objective To investigate the MRI features of primary central nervous system lymphoma(PCNSL)and the causes of misdiagnosis.Methods From July 2020 to February 2023,20 patients with PCNSL were selected,10 of whom were misdiagnosed.The MRI data of patients with and without misdiagnosis were analyzed to explore the imaging causes of misdiagnosis of PCNSL patients.Results There was headache in 15 patients,limb weakness in 11 patients,visual impair-ment in 7 patients and dizziness in 6 patients.A total of 30 lesions were detected in 20 patients,including 19 that were located in superficial brain tissue,7 in deep brain tissue,and 4 in the ventricle.There were 14 cases of single lesions and 6 cases of multiple lesions.There were 6 cases with necrosis.Ten patients of initial misdiagnosis were included in the misdiagnosis group,including 5 patients with metastatic tumor and 5 patients with brain glioma.The misdiagnosis lasted 10 d-2 months.There were significant differences in multiple lesions,hemorrhage and necrosis between correct diagnosis group and misdiagno-sis group(P＜0.05).After stereo-directional biopsy was performed on the sites significantly enhanced by the enhanced MRI scan for pathological examination,diffuse large B-cell lymphoma was confirmed.The patients were treated with high-dose methotrexate combined with radiotherapy.The patients were followed up for 1 year,showing stable condition,and no death was reported.Conclusion For PCNSL patients,when the MRI enhancement scan does not reveal typical signs,it is more likely to be misdiagnosed as other intracranial diseases.Intracranial space occupying multiple lesions,hemorrhage,and necro-sis are the factors of imaging misdiagnosis of PCNSL.Careful observation and identification,multidisciplinary consultation and early pathologic examination when necessary are conducive to reducing the misdiagnosis rate.