原発性小腸癌の外科手術—現状と問題点

Surgery Procedures of Primary Small Intestine Cancer

要旨●小腸癌はその希少性から，外科的治療における腸管切除範囲，リンパ節郭清範囲などを規定した標準術式は確立されていない．大腸癌取扱い規約における右側結腸の領域リンパ節の概念を空腸・回腸癌に適用すると，支配空腸・回腸動脈のSMA本幹からの分岐部が主リンパ節（N3），腸管近くで網目状に交通している部分を腸管傍リンパ節（N1），その中間を中間リンパ節（N2）とするのが実際的である．進行癌では，腸管は腫瘍より口側・肛側に10cmずつを確保し，中枢方向については腫瘍より10cm以内の腸管に流入する栄養血管を同定し，SMA本幹から分岐する箇所で切離する．回盲弁より10cm以内の腫瘍の場合は回盲部切除を検討する．

　Standard surgical procedures that define the range of intestinal resection and lymph node dissection in the surgical treatment for small intestine cancer have not yet been established. When the concept of regional lymph nodes in the right colon in the Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma is applied to jejunum/ileal cancer, the lymph nodes at the branch of the feeding jejunum/ileal artery from the SMA trunk is the main lymph node（N3）. Those feeding arteries communicate and form a net near the intestinal tract. It is practical to refer to the part intestinal lymph node（N1）where the feeding blood vessels communicate in a mesh near the intestinal tract, and the intermediate lymph node（N2）in the middle. In the advanced stages of cancer, the intestinal tract should be secured at 10cm on both the oral and anal sides of the tumor, and in the central direction, the feeding arteries that flow into the intestinal tract within 10cm from the tumor should be identified and cut off at the branch from the SMA trunk. For tumors within 10cm of the ileocecal valve, ileocecal resection should be considered.