Immunohistochemical studies on matrix metalloproteinase-9 (MMP-9) and type-IV collagen in endometrial carcinoma.

Immunohistochemical staining of MMP-9 and the type-IV collagen was performed on paraffin sections of endometrial carcinoma. Immunostaining in 129 cases of endometrial cancer detected MMP-9 in 19.0% of the cases. MMP-9 positive was shown in 30% of the cases with vessel invasion, and in 12.7% of the cases without vessel invasion (p < 0.05). MMP-9 showed positive in many cases with poor differentiation and lymph node metastasis, but still failed to achieve statistical significance. MMP-9 staining did not correlate with disease outcomes. We can not clarify that MMP-9 is associated with tumor-cell invasion and metastasis. Type-IV collagen deposition at the tumor-stromal border was studied in 58 cases of endometrial carcinoma in which disruptions were seen in varying degrees. The type-IV collagen in the primary lesion decreased as the differentiation decreased. Even in the lymph node metastasis lesions, the type-IV collagen was stained and was almost in agreement with the primary lesions. In the primary lesions, there was no relationship between MMP-9 staining and the type-IV collagen. It was suggested that the type-IV collagen observed in endometrial carcinoma was more concerned with the differentiation of the tumor than with the degradation by MMP-9.