抄録
The purpose of this study was to elucidate the relationship between clinicopathologic malignancy and the distribution of both cytokeratin 19 (CK19) and type IV collagen in tongue carcinoma. The localization of CK19 and type IV collagen was examined immunohistochemically in biopsy specimens of 44 cases of squamous cell carcinomas of the tongue. The positive rates of both CK19 and type IV collagen were measured using a multipurpose image processor. CK19 expression was evaluated by (1) the ratio of number of positive cases to the total number of cases, (2) the ratio of area of positive sites to the area of the tumor, and (3) the expression pattern. The localization of type IV collagen was estimated as the ratio of the segmental length of positive sites to the external length of the tumor. We alsoexamined the relationship between the immunohistochemical results and prognostic factors, including the degree of differentiation, the size of the primary tumor, the mode of invasion, the presence or absence of lymph node metastasis, and the malignancy grading score of Anneroth. The correlation in the positive rates between CK19 and type IV collagen was also examined.
The positive rates of CK19 were higher in poorly differentiated carcinomas than in other lesions. Expression pattern III, in which the positive cells were distributed over the entire of tumor cell nest, was more commonly detected, although no significant difference was evident. No correlation was found between the size of the primary tumor and the expression of CK19. Invasion mode 4 C/D and a high grade of histological malignancy were observed primarily in cases with the expression pattern DI for CK19. A high positive rate and CK19 expression pattern DI were prominent in the group with lymph node metastasis. Expression pattern Ill for CK19 was more frequently found in lymph node metastasis than in the primary tumor. Low positive rates for type IV collagen were noted in cases of differentiation grade HI, tumor size T 3/4, invasion mode 4 C/D, and lymph node metastasis. The positivie rate for type IV collagen was lower in cases with a CK19 expression pattern DI than in those with patterns I and II, although the correlation coefficient between the areawise positive rate for CK19 and the positive rate for type IV collagen was not high.
These results suggest that the distribution of CK19 and type IV collagen may be related to clinicopathologic malignancy in tongue carcinoma.
