Published online Feb 28, 2005. doi: 10.3748/wjg.v11.i8.1193
Revised: June 26, 2004
Accepted: July 27, 2004
Published online: February 28, 2005
AIM: To evaluate the significance of transforming growth factor beta (TGF β) expression, in correlation with histopathological parameters, at the front of invasion in T1 colorectal cancer (CRC) and presence of metastases.
METHODS: TGF β immunohistochemical expression was studied in 34 specimens of colorectal adenocarcinomas (pT1). A three-step avidin-biotinylated immuno-peroxidase (ABCu-NCL) staining technique was performed on 4-µm paraffin-embedded tissue sections with a monoclonal antibody to TGF β (Novocastra, NCL-TGFB, clone TGFB 17, dilution 1:40).
RESULTS: Seventeen (50%) out of 34 lesions were positive for TGF β expression. The TGF β-positive rate in patients with vascular invasion was significantly higher than in those without vascular invasion (11/14 cases, P<0.01, P = 0.005). The TGF β-positive rate was observed in 91.7% of patients with presence of tumor budding at the front of invasion (11/12 cases, P<0.01, P = 0.0003). A statistically significant correlation was found between the presence of lymph node metastases and positive expression of TGF β (14/16 cases, P<0.01, P = 0.0001). We also observed that the TGF β-positive rates in groups with distant and non-distant metastases were 92.8% and 20% respectively, and a significant correlation between TGF β expression and distant metastasis was shown (P<0.01, P = 0.00003).
CONCLUSION: The evaluation of TGF β expression of protein in association with histological parameters can be used as a parameter of the aggressiveness of pT1 CRC.