Insulin-like growth factor II mRNA binding protein 3 (IMP3) expression in cervical intraepithelial neoplasia and its relationship with HIV-infection status

Abstract

Background Cervical cancer is preventable through screening, and HIV treatment guidelines recommend that all HIV-infected women receive cervical cancer twice during the year after HIV diagnosis and annually thereafter. Different immunohistochemical markers have been studied to highlight cervical intraepithelial lesions of low and high grade, the most widely used being p16. Recent studies have shown that insulin-like growth factor mRNA binding protein 3 (IMP3) plays a role in the development of invasive squamous cell carcinoma from cervical dysplasia, both in histology and in liquid-based cytology. Methods: We evaluated the clinical significance of the immunohistochemical expression of IMP3 and p16 in histological samples of cervical intraepithelial neoplasia from 56 samples of HIV-positive and 30 samples of HIV-negative patients. Results: A significant difference was found in IMP3 and p16 protein expression between HIV-positive and HIV-negative specimens. All cases of HIV-positive low grade squamous intraepithelial neoplasia (L-SIL) with IMP3 expression progressed in high grade (H)-SIL. However, the HIV-positive patients with IMP3-negative L-SIL remained stable or had a negative follow up. The L-SIL of HIV-negative patients with IMP3 protein expression had an uneventful follow up. IMP3-positive H-SIL recurred with low- or high-grade dysplasia during follow up after conisation in both populations. All IMP3-negative L-SIL and H-SIL had negative pap tests at follow up. Conclusions: In HIV-positive cases, IMP3 showed a higher sensitivity than p16 in identifying patients at risk of progression and recurrence.