pit pattern観察による早期大腸癌の深達度診断

Diagnosis of Early Stage Gastrointestinal Cancer Invasion Depth via Pit Pattern Observation

要旨●クリスタルバイレット染色下でのpit pattern観察による大腸腫瘍性病変の診断において，腺腫・Tis〜T1a癌鑑別質診断成績は正診率80％，癌診断の感度43.8％，特異度93.9％であり，癌の深達度診断に関しては正診率84.8％，T1b以深浸潤癌診断の感度77.4％，特異度89.6％であった．病変の洗浄や染色の必要性など，操作がやや煩雑であり，また粘液，病変からの出血などを原因とした染色不良により診断できない症例も存在するが，精度の高い診断手法である．通常観察やNBI拡大観察で癌が疑われ，何らかの治療を行う必要があるような病変に対してはpit pattern観察による質の精査および深達度診断を行うことが望ましい．ただし，pit pattern観察で得られた情報は病変表層という，ごく一部分の情報であることを念頭に置くことが大切である．

　When we diagnosed colorectal neoplasms with magnification of pit patterns under crystal violet staining, the adenoma and Tis-T1a cancer differential diagnostic accuracy was 80%, the cancer diagnosis sensitivity was 43.8%, the specificity was 93.9%, the cancer invasion depth diagnostic accuracy was 84.8%, the T1b cancer invasion depth sensitivity was 77.4%, and the specificity was 89.6%. Although there are cases in which diagnosis cannot be performed because of the necessity of cleaning and staining the lesions, the slight complexity of the procedure, the presence of mucus, hemorrhaging from the lesion, and inadequate staining, diagnosis by magnification of pit patterns under crystal violet staining is a highly accurate diagnostic method. When cancer is suspected in conventional endoscopic observation and narrow-band imaging magnification and some kind of treatment is required, it is best to closely examine the lesion's properties with pit pattern magnification and diagnose its invasion depth. However, it is important to keep in mind that this information about the lesion surface gleaned from pit pattern magnification is a very small portion of the overall information.