Angiogenin expression in head and neck basaloid and conventional squamous cell carcinoma: a site- and stage-matched comparison.

BACKGROUND: Basaloid squamous cell carcinoma is an uncommon variant of squamous cell carcinoma (SCC). Angiogenin (ANG), a member of the ribonuclease super-family, is essential to tumor angiogenesis, but has also been implicated in tumor consolidation and proliferation. METHODS: ANG expression was first investigated in 12 head and neck basaloid squamous cell carcinomas (HNBSCCs) and compared with a control group of 24 site- and stage-matched conventional SCCs to establish whether the supposedly more aggressive biological behavior of HNBSCCs might be ANG-related. RESULTS: No significant differences were found between HNBSCCs, and SCCs in terms of recurrence, disease-free survival (DFS), or overall survival rates. In HNBSCC, we identified a trend toward a significant inverse correlation between endothelial ANG expression and DFS (statistical trend, P = 0.08). Endothelial ANG expression did not differ significantly in HNBSCCs and SCCs. A high ANG expression in carcinoma cells was directly associated with pT in both the HNBSCC (P = 0.04) and the SCC (statistical trend, P = 0.07) groups. ANG expression in carcinoma cells was significantly lower in HNBSCCs than in SCCs (P = 0.005). CONCLUSIONS: All the biological mechanisms investigated to date, including ANG-mediated angiogenesis or cell proliferation, have failed to confirm that HNBSCCs have a more aggressive behavior than matched SCC.