Lack of prognostic value of immunoreactivity for p62 oncoprotein in colorectal carcinoma.

Immunohistochemical staining for c-myc p62 oncoprotein (p62) was performed in 59 colorectal carcinomas using mouse monoclonal antibody against human c-myc protein (MYC1-6E10). The immunoreactivity for p62 was intense in 22 (37.3%), and weak in 37 (62.7%) of the tumors. Advanced disease and nodal metastasis were more frequently seen in tumors showing intense staining but the difference did not reach statistical significance. Sixteen patients have died of the disease but overall survival rates did not differ between patients with tumors showing intense staining and those with tumors showing weakly staining. In 50 patients undergoing grossly curative resection, local or distant metastasis developed in 15 patients. Immunoreactivity for p62 had no effect on the rate of recurrence or disease free survival rates in these 50 patients undergoing grossly curative resection. The present study revealed that the immunoreactivity for p62 had no prognostic value in colorectal carcinoma.