The immunohistochemical expression of BCL-2 oncoprotein in colorectal adenocarcinoma

The immunoreactivity for bcl-2 oncoprotein was determined in tumor tissue samples from 40 patients with colorectal adenocarcinoma. Positive immunoreactivity for bcl-2 oncoprotein was seen in 14 of the 40 tumor tissue samples (35%) and was found to be associated with a significantly higher incidence of synchronous liver metastasis (P = 0.043); however, there was no correlation between the immunoreactivity for bcl-2 oncoprotein and tumor size, depth of tumor invasion, lymph node metastasis, or clinical stage of the disease. Among 33 patients who had undergone curative resection, disease-free survival did not differ significantly between 10 with bcl-2-positive tumors and 23 with bcl-2-negative tumors (P = 0.498). The present study showed that the positive immunohistochemical expression of bcl-2 oncoprotein was associated with a significantly higher incidence of liver metastasis from colorectal cancer, but it had no effect on the disease-free survival of patients who had undergone curative resection.