Increased expression of laminin-5 and its prognostic significance in hypopharyngeal cancer.

OBJECTIVES

We investigated the clinicopathologic significance of laminin-5 gamma2 chain (LNgamma2) expression in 26 surgically removed hypopharyngeal cancers and compared the results with conventional prognostic factors elicited from hematoxylin-eosin (H&E) stained whole-mount laryngeal sections.

STUDY

DESIGN

Stainability of LNgamma2 was mainly evaluated at the invasive front of the cancer nests. Scoring was performed on the basis of a semiquantitative scale defined according to the number of immunopositive cancer cells (score 3, 2, 1, and 0). Stainability of LNgamma2 was also evaluated macroscopically at different tumor locations such as surface center, interstitial space, and invasive front. Status of cartilage and vascular invasion and patterns of tumor extension were evaluated from H&E stained sections. The results of LNgamma2 expression correlated with the tumor stages, neck node status, pathologic differentiation, and prognoses.

RESULTS

Among the 26 cases, 24 demonstrated positive LNgamma2 expression. Of these cases, 1, 14, 9, and 0 showed scores of 3, 2, 1, and 0, respectively. Positive expression of LNgamma2 at the invasive front was more prominent in the high-expression group, and surface center was often positive in the cases of low-expression group. Among the H&E stained prognostic factors, vascular invasion and infiltrative pattern demonstrated significant correlations with clinical outcome. Vascular invasion and infiltrative pattern were also closely related to positive LNgamma2 expression. Five-year survival rates of patients who showed high LNgamma2 expression were significantly poorer than in patients with low expression.

CONCLUSION

Hypopharyngeal cancers positive for LNgamma2 indicate a considerable risk for cancer progression and are closely related to prognosis. Increased LNgamma2 expression might be a prognostic indicator for squamous cell carcinomas of the hypopharynx.