Background: Maspin, a member of the serpin family of protease inhibitors, is known to be a tumor suppressor. Although the relationship between its expression and biological significance has been investigated in several types of cancer, the clinicopathological significance of maspin expression in colorectal cancer has not been fully elucidated.
Materials and methods: The expression of maspin in colorectal adenocarcinomas from 104 patients (Ti, T2: 20 patients, T3, T4: 84 patients) was investigated using immunohistochemical methods and the extent of tumor budding was evaluated.
Results: The expression of maspin was observed in 66% (69 of 104) of colorectal adenocarcinomas and was significantly correlated with the depth of invasion (p < 0.0001), higher Dukes' classification (p < 0.0001) and high-grade tumor budding (>9 foci in a field) (p = 0.0001); however, no significant correlation was noted concerning lymph node metastases, vascular invasion and tumor differentiation. The intensity of immunostaining was most strongly observed at the invasion front, especially at the site of tumor budding.
Conclusion: These results suggest that the expression of maspin may correlate with the aggressiveness of colorectal adenocarcinomas.