yemenjmedYemen Journal of MedicinecoVolume 3 Issue 1MultidisciplinaryEnglishJanuary-April 2024NNY20240511ArticleHypertrophic pachymeningitis during radiotherapy for locally advanced prostate cancer: A coincidental or causal relationshipEnglishY5456YukihiroHama1EnglishNEtsukoTate1EnglishY10.63475/yjm.v3i1.4509Hypertrophic pachymeningitis (HP) is a rare clinical disorder characterized by focal or diffuse thickening of the dura mater with various neurological manifestations. It is known to be associated with autoimmune diseases, infections, and neoplasms. However, a review of the literature did not reveal that HP occurs during radiotherapy for cancer. In this report, we present a rare case of HP during radiotherapy for cancer in a 71-year-old male patient with high-risk prostate cancer who developed a headache and abducens nerve palsy during radiotherapy following androgen deprivation therapy. Magnetic resonance imaging (MRI) revealed dura mater thickening without brain metastases. The cerebrospinal fluid analysis demonstrated elevated protein levels. The patient was diagnosed with HP and treated with oral prednisolone. Within 2 days of treatment, the headache subsided, and the abducens nerve palsy resolved completely after 6 months of radiotherapy. In view of these events, we suggested a possible correlation between radiotherapy and HP, particularly, if meningitis develops during radiotherapy in the absence of infection or cancer seeding.EnglishAbducens nerve palsy, Adverse effects, Dura mater, Hypertrophic pachymeningitis, Radiation-induced abnormalitieshttps://yemenjmed.com/admin/abstract?id=100References1619Matias TB, Cordeiro RA, Duarte JA, et al. Immune-mediated hypertrophic pachymeningitis and its mimickers: magnetic resonance imaging findings. Acad Radiol 2023:S1076-6332(23)00034-X doi: 10.1016/j.acra.2023.01.017Kupersmith MJ, Martin V, Heller G, et al. Idiopathic hypertrophic pachymeningitis. Neurology 2004;62:686-94 doi: 10.1212/01.wnl.0000113748.53023.b7Abrantes FF, Moraes MP, Rezende Filho FM, et al. A clinical approach to hypertrophic pachymeningitis. Arquivos de Neuro-Psiquiatria. 2020 Dec 7;78:797-804.Dash GK, Thomas B, Nair M, et al. Clinico-radiological spectrum and outcome in idiopathic hypertrophic pachymeningitis. J Neurol Sci. 2015 Mar 15;350(1-2):51-60Yahyapour R, Amini P, Rezapour S, et al. Radiation-induced inflammation and autoimmune diseases. Mil Med Res 2018;5:9Giaj-Levra N, Sciascia S, Fiorentino A, et al. Radiotherapy in patients with connective tissue diseases. Lancet Oncol 2016;17:e109-e117Mekinian A, Maisonobe L, Boukari L, et al. Characteristics, outcome and treatments with cranial pachymeningitis: A multicenter French retrospective study of 60 patients. Medicine. 2018;97(30):e11413.