杯状の形態を示しリンパ節転移を来した直腸カルチノイド（NET G1）の1例

Rectal Carcinoid（NET G1）Exhibiting a Scyphoid form with Lymph Node Metastasis, Report of a Case

要旨　患者は66歳，女性．血便を主訴に当科外来を受診し，大腸内視鏡検査を施行したところ，直腸Rbに18mm大の隆起性病変を認め，中央には発赤した陥凹面を認めた．陥凹辺縁から隆起の立ち上がりにかけて正常粘膜に覆われた粘膜下腫瘍様の像を呈し，短い茎を有する杯状の形態を示していた．各種検査にて，粘膜下層深部まで達する18mm大の直腸カルチノイドで，陥凹を伴っており，手術適応の病変と診断し，腹腔鏡下超低位前方切除術を施行した．切除病理標本にて，WHO分類NET G1のカルチノイド腫瘍であり，脈管侵襲陽性でリンパ節転移を認めた．

　The case pertains to a 66-year-old woman. She consulted our hospital with a chief complaint of bloody feces, and an 18mm elevated lesion was observed in the rectum Rb with a reddened recessed surface observed in its center. A submucosal tumor-like image covered with normal mucous membrane was exhibited from the end of the recession to the rise of the protrusion, exhibiting a scyphoid form comprising a short stalk. Upon various tests, the patient was diagnosed with an 18mm rectal carcinoid reaching to the deep part of the submucosa accompanying recession. Because of this, it was determined to be an operable lesion and laparoscopic super low anterior resection was carried out. The excised pathology specimen was determined to be a NET G1 carcinoid tumor according to the WHO classification. It was found to be positive for blood vessel invasion, and lymph node metastasis was observed.