Abstract

A total of 50 cases of gallbladder dysplasia found adjacent to carcinoma were examined histologically and immunohistochemically for metaplastic changes in order to elucidate the characteristics of the dysplasia of the gallbladder. The incidence of metaplastic changes in the dysplastic mucosa such as the occurrence of endocrine cells, lysozyme-immunoreactive cells, goblet cells, and Paneth cells were 58%, 74%, 32%, and 22%, respectively. Based on the presence or absence of metaplastic changes, these 50 cases of dysplasia were divided into 40 cases (80%) of metaplastic type dysplasia showing at least one marker of metaplasia and 10 cases (20%) of non-metaplastic type dysplasia showing no metaplasia. On the other hand, these 50 cases of carcinoma were divided into 10 cases of non-metaplastic type carcinoma and 40 cases of metaplastic type carcinoma based on the presence or absence of metaplasia in the tumor tissue. The incidence of metaplastic changes in the dysplastic lesions was compared between the dysplasia adjacent to non-metaplastic type carcinoma and that adjacent to metaplastic type carcinoma. The incidence of metaplasia in the dysplastic mucosa adjacent to metaplastic type carcinoma was higher than that adjacent to non-metaplastic type carcinoma with a statistically significant difference. Moreover, the presence or absence of metaplastic changes was also examined in the surrounding dysplasia and non-tumorous mucosa in each case. Most cases of metaplastic type carcinoma were surrounded by dysplasia with metaplastic changes and by metaplastic epithelium, whereas most cases of non-metaplastic type carcinoma were surrounded by dysplasia without metaplasia.(ABSTRACT TRUNCATED AT 250 WORDS)