High-fidelity DNA histograms in neoplastic progression in Barrett's esophagus

Abstract

This study describes the high-fidelity DNA histograms in different stages of neoplastic progression to Barrett's adenocarcinoma (BAC). High-fidelity DNA histograms were obtained with image cytometry on sections, and were classified based on DNA index values of the peaks into diploid, mild aneuploid, moderate aneuploid and severe aneuploid. Heterogeneity index (HI) representing cells with different DNA content and the 5N exceeding cell fraction were determined. One hundred and eighty-seven cases, including 34 normal gastrointestinal mucosa (control), 66 Barrett'sspecialized intestinal metaplasia (SIM), 22 low-grade dysplasia (LGD), 22 high-grade dysplasia (HGD) and 43 BAC were investigated. Controls showed sharp diploid peaks with HI values less than 13, and no 5N exceeding nuclei. SIM showed a spectrum of histograms including diploid, mild aneuploid and moderate aneuploid histograms. The frequency and severity of aneuploidy increased with worsening histological grades of dysplasia. All BAC cases were aneuploid, with moderate or severe aneuploidy. Marked elevated HI values (420) and 5N exceeding fractions (45%) were found in 5%, 32%, 50% and 88% of cases with SIM, LGD, HGD and BAC, respectively. The high-fidelity DNA histograms suggest that (1) Barrett's SIM may already be dysplastic in nature, and all BAC may be markedly aneuploid; and (2) elevated cellular DNA heterogeneity and 5N fractions may be markers of progressive chromosomal changes and 'unstable aneuploidy' that identifies progressive lesions.

Diagnosis and risk stratification of Barrett’s dysplasia by flow cytometric DNA analysis of paraffin-embedded tissue

“…However, by virtue of identifying a small number of abnormal nuclei from the area of interest, image cytometry may identify much higher rates of rare aneuploid cells that are not detected by flow cytometry 41. For instance, Yu et al reported that more than two-thirds of BO without dysplasia (69%) and LGD (82%) samples have aneuploid populations 49. Similarly, Fang et al demonstrated that up to 13% of BO without dysplasia and 60% of LGD samples showed DNA content abnormality 50.…”

Whole slide image cytometry: a novel method to detect abnormal DNA content in Barrett's esophagus

“…This has been reported previously and attributed to the intrinsic characteristics of performing DNA ploidy analysis using thin tissue sections. 43,64 Thick tissue sections (e.g., 410 μm) create difficulty in nuclei segmentation, especially in situations of touching and overlapping nuclei. Therefore, biased sampling error could happen where smaller and isolated nuclei are preferred.…”

“…18,38,39 Nonetheless, the majority of other studies are still focusing on the well-established DNA density measurements using tissue sections (e.g., 3-7 μm), especially the use of the commercially available ACIS system (Automated Cellular Imaging System, Dako, Denmark) from a field of view (FoV) of tissue sections. [40][41][42][43][44] Under a microscope at × 40 magnification, a FoV is digitally captured followed by image analysis to locate nuclei and to measure the integrated optical density (IOD) for each nucleus. DNA content histogram for FoV can then be constructed.…”

The Case for Endoscopic Treatment of Non-dysplastic and Low-Grade Dysplastic Barrett’s Esophagus

“…In some studies, aneuploidy heralds an aggressive genotype [42,[48][49][50]. DNA content abnormalities, similar to those found in LGD, occur in the basal portions of crypts in ND epithelium [51].…”