Adachi VI型腹腔動脈走行異常を伴う早期胃癌に対する腹腔鏡下幽門側胃切除6番リンパ節郭清術

No. 6 lymph node dissection of laparoscopic distal gastrectomy in a gastric cancer case with arterial abnormality of Adachi type VI

◆要旨：症例は75歳，女性．早期胃癌の加療目的に当院へ紹介された．術前の造影CTおよび3D血管構築では，総肝動脈が上腸間膜動脈から分枝し門脈の背面を走行するAdachi VI型の血管走行異常を認めた．精査の結果，胃癌 M, Less, cT1aN0M0 cStage I の術前診断を得て，腹腔鏡下幽門側胃切除術を施行した．通常Adachi VI型の血管走行の場合はNo.8aリンパ節の郭清が問題となるが，本症例では，網囊右側の生理的癒着が軽度であり，右胃大網動静脈の血管茎が通常よりも外側にあったため，No.6リンパ節郭清に時間を要した．血管走行異常症例に関しては，術前3D CTによる血管走行の把握だけでなく術中所見にて周囲臓器との関係を理解することが重要であり，より慎重な腹腔鏡操作が必要と考えられた．

　A 75 year-old female was referred to our hospital for treatment of early gastric cancer （GC）. Computed tomography （CT） with 3D angiography by volume rendering revealed that this patient had Adachi type VI arterial abnormality; common hepatic artery was branched from superior mesenteric artery, running behind the portal vein. The patient was diagnosed with early GC M Less cT1aN0M0 cStage I, and laparoscopic distal gastrectomy was performed. In Adachi type VI, No.8a lymph node （LN） dissection is reportedly difficult. However, in this case, No.6 LN dissection was difficult because adhesion on the right edge of omental brusa was not formed, and right gastro epiploic artery/vein were located far from the stomach. In a case with arterial abnormality, it is important to pay more attention to the surgical findings as well as to use preoperative 3D CT.