肛門管に浸潤した直腸癌に対する腹腔鏡下内括約筋切除術―自然肛門温存術を目指したS-1による術前化学放射線療法が奏効した1例―

Laparoscopic intersphincteric resection for advanced rectal cancer extending to the anal canal : an effective case treated by preoperative chemo-radiationtherapy using S-1 for preserving the anus

◆要旨：患者は76歳，女性．肛門管へ浸潤したcT2, N0, M0直腸癌に対して，S-1を用いた術前化学放射線療法を施行した．治療経過中にGrade3の下痢のためS-1を中止としたが，その後重篤な副作用はなかった．術前chemoradiotherapyによって腫瘍の著明な縮小を認めたため，肛門温存を目的に腹腔鏡下内括約筋切除術を行った．切除検体では，筋層内にわずかな癌胞巣を認めるのみで（ypT2, N0, M0, Grade 2），radial marginを含めて外科的切除線は陰性であった．術後特に大きな合併症はなく退院となり，現在まで再発は認めていない．

　We performed pre-operative chemo-radiation therapy （CRT） using S-1 on 76-year- old women with rectal cancer extending to the anal canal.. The use of S-1 was terminated due to grade 3 diarrhea during the pre-operative CRT course. Besides this diarrhea, there was no severe adverse event. Remarkable reduction in tumor size was observed and laparoscopic subtotal intersphincteric resection for the lesion was performed. The tumor cells were histologically identified only in the muscluralis propriae of the specimen, and there was no tumor cell at any of the surgical margins （Grade 2）. Pre CRT using S-1 was effective, and laparoscopic intersphincteric resection was performed safely on our patient with rectal cancer extending to the anal canal. 110/250 words