術前超音波内視鏡下穿刺吸引細胞診にて診断し，腹腔鏡補助下低位前方切除術を施行した直腸カルチノイドの1例

A case of rectal carcinoid tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration biopsy and treated by laparoscopic assisted low anterior resection

　患者は47歳，男性．直腸に腫瘍径20mm程度の腫瘤を認めた．EUS-FNAB（endoscopic ultra-sound-guided fine neadle aspiration biopsy）にて深達度は固有筋層の直腸カルチノイドと診断され，腹腔鏡補助下LAR（low anterior resection）を施行した．カルチノイドは粘膜下腫瘍の形態を取るため，EUS-FNAは深達度を含めた確定診断に有用であると思われた．また，腫瘍径の増大に伴ってリンパ節転移の頻度が上昇するため，11〜20mmの腫瘍に対する術式はさまざまである．本術式は根治性と低侵襲性を伴っており，下部直腸カルチノイドの手術法として考慮されるべき術式であるといえる．

We encountered a case of lower rectal carcinoid measuring 20 mm in diameter. A 47-year-old man was admit-ted to our hospital due to rectal bleeding. Colonoscopic examination showed a single protruding lesion in the lower rectum. We conducted fine needle aspiration biopsy (FNAB), and histological examination demonstrated carcinoid tumor. We performed laparoscope assisted low anterior resection (LAR) of the rectum. Carcinoid tu-mors generally appear as submucosal nodules. Therefore, pre-operative endoscopic diagnosis is difficult unless biopsy provides a correct histological diagnosis.