TMA sections co-stained for C9 and C5b-9 were evaluated for staining intensity in regions of specific tissue phenotypes (NSE: normal squamous epithelium, BE: Barrett’s Esophagus, LGD: Low grade dysplasia, HGD: high grade dysplasia, HGD+IEC: HGD with intraepithelial carcinoma, EAC) using a semi-quantitative scoring system from 0 to 3 by a specialist gastrointestinal pathologist (Figure 1). The gene discussed is ENO2; the disease is in situ carcinoma.