4．深達度診断における生検診断の意義

The Usefulness of Biopsy Specimens to Diagnose the Invasive Depth of Gastrointestinal Cancer

要旨　消化管浸潤癌の生検標本から深達度診断が可能かどうかについて検討した．浸潤癌と診断された症例は，食道癌21病変中8病変（38％），胃癌120病変中40病変（33％），大腸癌34病変中16病変（47％）と低率であった．しかし，深達度別にはsm以深の食道癌，大腸進行癌は浸潤癌と生検診断される割合が比較的高い結果であった．肉眼型は，食道癌では表在平担型，胃癌では表面型と3型，大腸癌では隆起型病変で浸潤癌と診断されにくい傾向であった．また，いずれの臓器も生検標本では浸潤癌であることが診断できても深達度を推定することは困難であった．しかし，食道癌ではm癌とsm以深の癌の区別，また，大腸癌ではsm癌と進行癌のおおよその区別は可能であると思われた．浸潤癌と生検診断されなかった症例の検討から，詳細な肉眼観察に基づいた診断，最深部からの正確かつ十分な量の標本採取が必要であると考えられた．

　To clarify the usefulness of biopsy specimens to diagnose the depth of invasion, biopsy specimens were analyzed clinicopathologically with their surgical specimens. Surgically resected 21 cases of invasive esophageal cancer, 120 cases of invasive gastric cancer and 34 cases of invasive colon cancer were investigated. 8 cases (38%) of esophageal cancer, 40 cases (33%) of gastric cancer and 16 cases (47%) of colon cancer were diagnosed through biopsy specimens as invasive cancer. Generally, a high proportion of advanced esophageal and colon cancers can be assumed to be invasive cancer. On the other hand, superficial and flat type esophageal cancer, superficial type and type 3 gastric cancer and protruded type colon cancer tended to be assumed to be non-invasive. It was very difficult to diagnose the depth of invasion, even if it could be assumed to be an invasive cancer, based on the findings of the biopsy specimen, but it does seem possible to distinguish through biopsy specimens intra-mucosal esophageal cancer from advanced cancer, and also submucosal colon cancer from advanced cancer. Our results revealed that careful macroscopic observation of tumors and biopsy specimens with sufficient volume, taken from their deepest part are needed for correct clinical diagnosis concerning the depth of invasion.