Use of Immunohistochemical Expression of IMP3 in the Risk Stratification of Patients with Barrett's Esophagus-Related High Grade Dysplasia (BE-HGD)
Aneta Bakula, Richard Cartun, Debbie Z Sterns, Pamela Newcomb, Jason Burghardt, Saverio Ligato. Hartford Hospital, Hartford, CT
Background: The aim of our study was to determine whether the pattern of IMP3 expression in patients with BE-HGD is associated with a higher risk for an adverse clinical outcome.
Design: Immunostain for IMP3 was evaluated in 40 gastroesophagectomies [10 with HGD only, and 30 with HGD plus adjacent superficially invasive adenocarcinoma (HGD/T1)]. In the HGD/T1 group, IMP3 was assessed both in the invasive component and in the adjacent HGD. Absence of expression or focal positivity of IMP3 (5% or less) was considered negative. Our end-point was to establish if there is any difference in behavior and clinical outcome, assessed by presence of lymph node metastasis (LNM) and overall survival, between IMP3-positve and IMP3-negative HGD patients.
Results: None of the 10 cases with only HGD expressed IMP3, had LNM or DOD. 13/30 cases with HGD/T1 were IMP3 negative both in the HGD and invasive component, and none had LNM or DOD. Instead, IMP3 expressed strong cytoplasmic granular staining in the remaining 17 of 30 (56.6%) cases with HGD/T1 both in the invasive component and in the adjacent HGD, and of these, 2/17 (11.7%) had LNM and DOD. (See table) The difference in outcome between IMP3 positive and IMP3 negative HGD was statistically significant. Chi-Square p<.0001.
|Category||# of cases||IMP3+||IMP3-||# Positive for IMP3 (%)||LNM (%)||DOD (%)|
|HGD only||10||0||10||0/10 (0)||0/10 (0)||0/10 (0)|
|HGD with T1||30||17||13||17/30 (56.6)||2/17 (11.7)||2/17 (11.7)|
|Total||40||17||23||17/40 (42.5)||2/40 (42.5)||2/40 (42.5)|