Conclusion
Myoferlin expression could be a potential prognosticator in patients with ccRCC, and might be a useful marker for oncologic surveillance in such patients.
Methods
One hundred and fifty-two patients with ccRCC who underwent treatment at Gyeongsang National University Hospital, Korea, between January 2000 and December 2009 were enrolled. Immunohistochemical analysis was performed on tissue microarray blocks produced from surgical specimens. Surgical specimen cancerous cells were graded as showing myoferlin hyperexpression or hypoexpression by comparison with intratumoral endothelial cells. Disease-free survival was evaluated using Kaplan-Meier analysis. Cox regression analysis was used to determine the relationships between myoferlin expression levels, risk factors, and prognosis.
Results
Seventy-one of 304 cores exhibited myoferlin hyperexpression. T stage was not associated with myoferlin hyperexpression, whereas a high Fuhrman nuclear grade was significantly associated with myoferlin hyperexpression. Kaplan-Meier analysis revealed that patients with T stage >2, Fuhrman nuclear grade >2, and those with myoferlin hyperexpression had poorer disease-free survival compared to those with lower T stage, lower Fuhrman nuclear grade, and myoferlin hypoexpression (all p <0.001). Furthermore, myoferlin hyperexpression was significantly associated with disease-free survival on Cox regression analysis (hazard ratio, 4.604; 95% confidence interval, 1.893-11.199; p = 0.001).