Hyaluronan expression in gastric cancer cells is associated with local and nodal spread and reduced survival rate.

Hyaluronan (HA), an extracellular high-molecular-mass polysaccharide, is supposed to be involved in the growth and progression of malignant tumours. We studied the cellular expression of HA in 215 operated stage I-IV gastric cancer patients using a specific biotinylated probe. Most (93%) of the tumours showed HA staining in their parenchyma, whereas the stroma inside and around the tumour was stained in every case. When HA expression was compared with the clinical and histological features of the tumours, a strong staining intensity in the tumour parenchyma was found to be associated with deep tumour invasion (pT3 or 4) and with mixed type of Laurén. A high proportion of HA-positive cells of all neoplastic cells was significantly associated with deep tumour invasion, nodal metastasis, positive lymphatic invasion, poor differentiation grade, as well as with inferior prognosis in univariate survival analysis. However, in multivariate analysis, only pT, pN, and vascular and lymphatic invasion emerged as independent predictors of survival in gastric cancer. The results indicate that ectopic HA expression is a frequent feature of gastric adenocarcinoma, and is associated with tumour progression and poor survival rate.