[Immunohistochemical study of the extracellular matrix in non-small cell lung cancer: relation to lymph node metastasis and prognosis].

The distribution of type IV collagen and laminin in the basement membrane (BM), and fibronectin in the peritumoral stroma of 112 lung cancers (62 adenocarcinomas, 50 squamous cell carcinomas) was studied using immunohistochemical techniques to compare with tumor size, lymph node metastasis and prognosis. In normal lung tissues, type IV collagen and laminin stainings were continuously linear in bronchial BM, blood vessel BM, around bronchial gland and along alveolar septa. Immunoreactivity of fibronectin was shown in BM and stroma. In lung cancers, type IV collagen and laminin stainings were observed in continuous or discontinuous pattern around carcinoma cells, and partially unrecognizable. Staining patterns were divided into continuous (C) and discontinuous (D). And fibronectin patterns were divided into weakly and strongly positive. In relation between staining pattern and lymph node metastasis, in adenocarcinomas, C pattern of type IV collagen staining without lymph node metastasis occurred in 73.9% and with metastasis in 26.1%, on the other hand, D pattern without lymph node metastasis occurred in 25.6% and with metastasis in 74.4%. The correlation was statistically significant (p less than 0.01). And also, in squamous cell carcinomas, C pattern without lymph node metastasis seen in 71.4% and with metastasis in 28.6%, on the other hand, D pattern without lymph node metastasis seen in 27.6% and with metastasis in 72.4%. The correlation was statistically significant (p less than 0.01). But staining pattern of fibronectin didn't correlate to lymph node metastasis. In comparison between C and D patterns, C pattern was associated with longer survival than D pattern (p less than 0.01). In lung cancers without lymph node metastasis, C pattern tended to be higher in 5-year-survival than D pattern, but not significant. These findings suggest that staining pattern of type IV collagen and laminin might be correlated to cancer metastasis and useful to estimate the prognosis.