IMP3, an Oncofetal Protein, Is a Useful Diagnostic Biomarker for Hepatocellular Carcinoma.
Michal Kamionek, Zhong Jiang, Peiguo Chu, Kenneth Rock, Dina Kandil. UMass Memorial Medical Center, Worcester, MA; City of Hope National Medical Center, Duarte, CA
Background: IMP3, an oncofetal protein, plays an important role in tumor proliferation and invasion. Studies have shown that expression of IMP3 is associated with epithelial dysplasia and invasive cancers. However, little is known about expression of IMP3 in hepatocellular lesions of liver. In this study, we investigated expression of IMP3 in benign and malignant lesions of liver to define usefulness of IMP3 as marker for detection of hepatocellular carcinoma (HCC).
Design: A total of 230 hepatocellular primary and metastatic lesions were retrieved from the surgical pathology files of a large Academic Medical Center. These included resection and biopsy specimens from 7 adenomas, 30 Focal nodular hyperplasia (FNH), 52 cirrhotic livers, 129 HCC and 12 metastatic HCC. All cases were stained with antibody against IMP3 protein.
Results: All benign lesions including cirrhosis (0/52), FNH (0/30) or adenomas (0/7) were negative for IMP3. From the pool of 129 HCC (79/129), 61.24% cases were positive for IMP3. Additionally, 83.3% of metastatic HCC (10/12) were positive for IMP3. In biopsy material, expression of IMP3 was detected in 71.83% (51/71) of HCC cases. However, the sensitivity of IMP3 varied from 52.0% in well-differentiated HCC up to 93.3% in poorly differentiated tumors in biopsy material.
Conclusions: Our data provide important baseline information for IMP3 expression in benign and malignant hepatocellular lesions. IMP3 is a useful biomarker for differentiating benign lesions from HCC in challenging cases. The expression of IMP3 in tumor cells can increase the level of confidence in establishing a definitive malignant diagnosis, especially in biopsy material.
Tuesday, March 1, 2011 1:00 PM
Poster Session IV # 74, Tuesday Afternoon