類上皮腫に合併した乳癌治療後27年で発症した癌性髄膜炎の1例

Leptomeningeal Carcinomatosis Following 27 Years Remission from Breast Cancer with Epidermoid: A Case Report

Ⅰ．はじめに

　乳癌は転移性脳腫瘍を来す頻度が高く，特に癌性髄膜炎，髄膜播種の頻度は他の癌腫に比較し高い¹²⁾．乳癌治療後，頭蓋内病変を来すまでの期間は比較的長いものの，長期間再発所見がなく癌性髄膜炎を呈する例は極めて稀である．

　良性腫瘍である類上皮腫は自然破裂によるchemical meningitisを来すことがある¹⁶⁾．今回われわれは，髄膜炎症状を呈した症例で，この2つの病態が存在したため，確定診断に苦慮した症例を経験したので報告する．

　We herein report a patient with leptomeningeal carcinomatosis (LC) in long-term remission from breast cancer,co-existing with a posterior fossa epidermoid and an increase in the serum CA19-9 level which complicated the diagnosis. A 59-year-old woman underwent a left mastectomy due to breast cancer 27 years ago. She was admitted to our hospital suffering from a headache and diplopia. Her serum CA19-9 level on admission was elevated,and diffusion weighted images showed a high-intensity tumor in the prepontine and left cerebello-pontine cistern. A left lateral suboccipital craniotomy with endoscopic assistance was performed for tissue sampling. The pathological diagnosis was an epidermoid and LC from breast cancer. She died of progression of leptomeningeal carcinomatosis 31 days after surgery.

　LC alone following long-term remission from breast cancer is extremely rare. Meningeal irritation co-existing with an epidermoid mimicking chemical meningitis is even rarer. Pathological confirmation is required for such rare cases.