ロボット支援胸腔鏡下被膜内切除により神経障害性後遺症を回避しえた腕神経叢下幹由来の神経鞘腫の1切除例

A schwannoma arising from the inferior trunk of the brachial plexus treated by robot-assisted thoracoscopic intracapsular resection, avoiding mid-term neuropathic sequelae : A case report

◆要旨：症例は43歳，男性．健診の胸部単純X線写真で緩徐に増大する右肺尖部の結節影を指摘された．自覚症状はなかった．MRI画像で第1胸神経と連続する最大径19mmの腫瘍を認め腕神経叢由来の神経鞘腫と診断した．利き腕である右手の神経障害が懸念されたが，腫瘍の増大傾向のためロボット支援胸腔鏡下腫瘍被膜内切除術を施行した．術後翌日より右前腕の痺れと第2指，第3指の深指屈筋の筋力低下を認めたが，ビタミンB₁₂製剤投与と第8頸神経からの再支配によって，術後3か月で右上肢の神経症状は完全に消失し，術後1年のCT画像では腫瘍の局所再発を認めなかった．ロボット支援胸腔鏡下被膜内切除術は，中期的な神経障害性後遺症発生の回避に有用であった．

　A 43-year-old, asymptomatic man was referred to our hospital because of a right pulmonary apex nodule noted on plain chest radiograph during periodic health check-up. A magnetic resonance imaging showed a tumor with a maximum diameter of 19mm contiguous with the first thoracic nerve root, and the diagnosis of schwannoma originating from the brachial plexus was made. There were concerns about nerve damage to his dominant hand, but due to increasing tendency of the tumor, a robot-assisted thoracoscopic intracapsular resection was performed. The patient experienced numbness in the right forearm and weakness of the deep flexor muscles of the second and third fingers from the day after the operation. With vitamin B₁₂ administration and reinnervation from the eighth cervical nerve, the neurologic symptoms in the right upper extremity completely resolved 3 months after surgery, and a computed tomography scan at 1 year after surgery showed no sign of recurrence. Intracapsular resection using the surgical robotic system was successful in avoiding neurological sequelae.