微小胃癌のX線診断

X-ray Diagnosis of Minute Gastric Cancer

　1969年の秋の日本消化器内視鏡学会では1cm以下を微小癌とした．「胃と腸」5巻8号の特集号（「診断された微小胃癌」）でX線，内視鏡，および，肉眼所見が議論されている．しかし，病理側は5mm以下を微小癌と定義する．そこで，5mm以下のものの診断を考察することにする．

　中村らはすでに多数の症例を集めている．それによると，約4％にsmの微小癌をみている．全身転移した多発微小癌例も，慶大，順大で報告しているから，微小癌例でも，決して安心できないとおどかされる．

　Eight cases with 19 lesions of minute gastric cancer were macroscopically and radiologically reviewed and the following results were obtained.

　1. 32% of the 19 lesions were considered as a benign lesion with the postoperative macroscopic appearances of the resected specimens, and no abnormalities were detected in the remaining 68% of them. None of them could be macroscopically diagnosed as malignancy.

　2. A diagnostic accuracy was raised with the X-ray findings on the postoperative roentgenogram. 20% of the 19 lesions looked malignant, and 26.6% of them were diagnosed as benign erosion. Abnormal appearance in the areae gastricae was seen in 20% of them, but no abnormality was noted in the remaining 33% (Fig. 2). The preoperative X-ray views of these cases were retrospectively analyzed with the results of postoperative roentgenograms. A retrospective diagnosis was cancer in 11%, benign erosion in 16%, ulcer scar in 5% of them. There could not be seen any abnormality in the remaining 68% even at the retrospective review.

　3. Some of minute cancers about 1mm in size could be picked-up by the postoperative roentgenogram. Nearly all minute cancers between 2 and 3mm in size were possible to pick-up on the postoperative roentgenogram and a diagnosis of malignancy was made in some of them. However, preoperative detection may be possible in some of them. Minute gastric cancers around 5 mm in size can be preoperatively detected and their natures can be determined.

　4. For the detection of minute gastric cancer, fine mucosal abnormality must be visualized on the X-ray views. The fine mucosal abnormality could be demonstrated at one out of four X-ray examinations. It is a very difficult task to visualize minute gastric cancer. A X-ray sign of minute cancer was a faint barium patch.

　5. All minute gastric cancers detected were along the lesser curvature or on the posterior wall of the angle. Detection of minute cancer on the anterior wall or at the cardiac region is impossible by the present methods of X-ray examination.