胃癌と胃非上皮性良性腫瘍との併存例―とくに併存した胃良性腫瘍に浸潤した胃癌症例

Gastric Cancer Coexisting with Gastric Benign Mesenchymal Tumor

　胃の各種診断法の進歩と共に，切除胃の綿密な検索により，最近，稀な胃疾患が発見されることが多くなってきた．たとえば，胃癌と胃の非上皮性良性腫瘍の両腫瘍が，同一胃に共存することは稀であるが，とくに併存する非上皮性良性腫瘍に癌浸潤のみられた症例の報告は文献的に見当らない．

　筆者らは，このような2例を経験し，次いで良性腫瘍と癌とが近接して存在した1例も得たので，これらを報告し，その癌発生などに関して考察を加えた．

　Case 1, a 57-year-old female harbored an elevation on the posterior wall of corpus ventriculi when examined by x-ray two years previously. In the present operation a crater was found adjacent to the proximal side of the elevation. Histologically the crater proved to be carcinoma simplex and the elevation to be lipoma existing in the submucosal layer, cancer invasion being slightly found in the liporna.

　Case 2, a 65-year-old male was found with a crater on the cardia on x-ray. Total gastrectomy revealed the crater to be Ul-Ⅲ, having several leiomyomas with their centers hyalinized in tunica muscularis propria of the proximal and distal margins of the crater. Cancer invasion was observed from crater margin to the deep ulcerated area and partially into the leiomyomas.

　Case 3, a 70-year-old male was found with a submucosal tumor on the greater curvature of the antrum on stomach x-ray and gastrocamera done three years previously. The present resected specimen revealed a 7.0×6.0 cm carcinoma, Borrmann II, centering on the anterior wall of the antrum. On the serosal side of the carcinoma was found a well-developed leiomyoma showing a growth mostly outside the gastric wall. The leiomyoma contained no cancer infiltration.

　In addition to the above three cases, two cases with the co-existence of benign mesenchymal tumor and carcinoma are reported as to their rareness. It is noteworthy that no case has been found in the Japaness literature, in which gastric cancer shows an invasion into a co-existing benign mesenchymal tumor of the stomach. Possible relations of benign tumor with the development of cancer are discussed in reference to the unlikeliness of cancer infiltration into benign tumor. Stress is laid on the importance of being very careful in diagnosing and treating such uncommonly complicated cases.