[Assessment of the basal membrane status as prognostic factor in renal carcinoma].

Objectives: To know the basal membrane (BM) integrity in renal cell carcinoma (RC) and its importance as prognostic factor.
Material and Methods: 73 patients with RC were selected. Immunohistochemistry with monoclonal antibodies against basal proteins laminin and collagen IV was performed. Percentage for BM fragmentation in the whole tumour was considered taking 75% as cut off.
Results: Follow-up was 6.3 +/- 4.3 years and 27 patients progressed. Correlation between laminin and collagen IV was significative (p = 0.000). A BM fragmentation expressed with laminin bigger than 75% was related to tumoural symptoms (p = 0.019), worse grade (p = 0.004) and necrosis in more than 10% of the tumour (p = 0.000). Fragmentation observed with collagen IV was associated to tumours greater than 7 cm (p = 0.014). Those patients whose tumours displayed more than 75% of BM fragmentation, measured with collagen IV, presented worse survival (p = 0.042). A similar trend was observed in the case of laminin, but it did not reach statistic significance (p = 0.119). In the unvariated analysis grade III-IV, more than 10% of necrosis within the tumour, tumoural symptoms and BM fragmentation bigger than 75% measured with collagen IV were prognostic, while only grade and necrosis did so in the multivariate analysis.
Conclusions: Collagen IV and laminin represent nicely, with a similar expression pattern, the BM fragmentation in RC. Within a battery of immunohistochemical markers to study RC at least one of them should be included because their prognostic implication.