Prognostic significance of basement membrane deposition in operable squamous cell carcinomas of the lung.

Tumor histology, stage of disease, and performance status are the most important prognostic factors in squamous cell lung cancer (SqCLC). A potentially important descriptor is the pattern of tumor growth as reflected in the dissolution of preexisting or deposition of newly formed basement membrane (BM) around tumor cell nests. The possible correlation between the pattern of BM deposition and patient survival was investigated. Immunohistochemistry testing, using polyclonal antibodies to human type IV collagen, was done on tumor samples of 68 patients with operable Stages I or II SqCLC, and BM staining was scored semiquantitatively. More than 75% immunoreactivity was scored as extensive BM and less than 75% as moderate or limited BM. In six patients, no immunoreactivity could be detected. In 27 of 62 patients, extensive and, in 35 of 62 patients, moderate-limited BM deposition was found. This deposition had a significant effect on survival (P = 0.02). Cox regression analysis, including BM deposition and tumor stage, indicated that BM deposition might also have value as an additional independent prognostic indicator for survival (P = 0.02). Deposition of an appreciable amount of BM in the center of the SqCLC was a prognostically favorable sign, independent of tumor stage.