Macrophages, inflammation and risk of cervical intraepithelial neoplasia (CIN) progression—Clinicopathological correlation

Abstract

To evaluate the population of macrophages during the cervical malignant transformation and its influence in CIN outcome. Biopsies from 26 normal cervix, 28 low-grade (LSIL), 30 high grade squamous intraepithelial lesions (HSIL) and 28 squamous cell carcinomas (SCC) were stained by H&E to assess inflammation and by immunohistochemistry with anti-CD68 to detect macrophages. The macrophage count was corrected for the epithelial and stromal compartments using appropriate software. Clinical and prospective follow-up data were also available. We identified that macrophage count increased linearly with disease progression (median count per case at x200 magnification: normal, 5.1; LSIL, 5.5; HSIL, 9.9; SCC, 14.5; P<0.001), that inflammation also increased (moderate-intense inflammation present in 25%, 46.1%, 58.4% and 89.3% of normal, LSIL, HSIL and SCC, respectively; P<0.001) and that macrophage count was independently associated with the lesion grade (P<0.001). Moreover, macrophages showed an increasing migration into the epithelium along with the progression of CIN to invasive cancer. Of the 24 LSIL cases with information available, followed-up for 805+/-140 days, 16 regressed, 6 persisted and 2 progressed. Age, high-risk HPV or inflammation were not risk factors for persistent/progressed LSIL in our cohort. However, LSIL that persisted or progressed showed a higher macrophage count (median of 10.8) than lesions that regressed (7; P=0.031). The study on macrophages offers a potential approach for cervical cancer treatment, since macrophages are closely related to progression of CIN, and can be used as an applicable marker of such a risk.