Since inflammatory diseases and precancerous lesions of esophagus require clinico-morphological diagnostics, it includes histological verification of endoscopic lesions in line with specific protocols of biopsy taking according to endoscopic findings and expected diagnosis. This review elucidates pathogenesis of gastroesophageal reflux disease (GERD) specter and focuses on detailed features of histologic diagnostics of Barrett’s esophagus and Barrett’s dysplasia. Precise histologic diagnosis in this group of patients implies appropriate treatment and defines prognosis.

Introduction. The incidence of esophageal cancer is rising worldwide; however, this disease is often diagnosed at advanced stages, which leads to poor prognosis and low 5-year survival. Thus, the search for prognostic predictors for both adenocarcinoma and squamous cell carcinoma of the esophagus is necessary. The aim of our study was to evaluate the immunohistochemical profile of markers that define differentiation and biological behavior of squamous cell carcinoma and adenocarcinoma of the esophagus. Materials and methods. The research included 100 patients with morphologically proven esophageal cancer. Biopsy specimens of esophageal mucosa obtained during EGDS were fixed in 10% buffered formalin and stained with hematoxylin and eosin and combined PAS/Alcian blue. We performed immunohistochemical evaluation with the following markers: p53, p16, Ki-67, CK5/6, p63, MUC5AC, MUC6, and MUC2. Results. Forty patients had squamous cell carcinoma, 53 adenocarcinoma, and 7 anaplastic cancer. High p53 expression was shown in 45.83% of patients with squamous cell cancer and in 50% of patients with adenocarcinoma (no statistical difference: p>0.05, Fisher’s test). High p16 IHC level prevailed in adenocarcinoma (54% vs. 8.33%, p<0.05, Fisher’s test). In both cancer types, high p16 IHC level was more common in patients with low p53 IHC level. High Ki-67 more often coincided with high p53 IHC levels in both histological types of esophageal cancer (p<0.01, Fisher’s test). Conclusion. Immunohistochemical evaluation with p53, p16, and Ki-67 in adenocarcinoma and squamous cell carcinoma provides valuable information for disease prognosis. Keywords: esophageal cancer, esophageal adenocarcinoma, esophageal squamous cell carcinoma, prognosis, immunohistochemical markers, p53

Introduction. The incidence of gastroesophageal reflux disease, Barrett’s esophagus, and esophageal adenocarcinoma is rising. Eosinophilic esophagitis is the second most common non-neoplastic esophageal disease. The study aimed to evaluate the nosological spectrum of esophageal pathology in a multidisciplinary hospital based on esophageal biopsy specimens in the pathology department. Materials and methods. The study included 622 patients who underwent esophagogastroduodenoscopy with biopsy. Biopsy specimens were fixed in 10% neutral buffered formalin and routinely stained with haematoxylin and eosin, combined PAS/Alcian blue, and Mallory stain. Histopathological assessment of biopsies in patients with eosinophilic esophagitis was performed using the EoEHSS. Results. Non-neoplastic esophageal diseases were detected in 325 patients (52.25%), precancerous diseases, in 118 patients (18.97%); benign neoplasms, in 120 patients (19.29%); and malignant tumors, in 59 patients (9.49%). Among patients with esophagitis, chronic nonspecific and reflux esophagitis accounted for 65.93% of cases, while eosinophilic esophagitis was diagnosed in 28.57%. Complications of gastroesophageal reflux disease were distributed as follows: Barrett’s esophagus was observed in 50.22% of patients; columnar-lined esophagus with gastric-type metaplasia, in 39.21%; esophageal ulcer, in 9.25%; and esophageal stricture, in 1.32%. The rate of dysplasia in Barrett’s esophagus was 21.93%, whereas in gastric type metaplasia of distal esophagus, 4.49% (p<0.05). Thus, dysplasia in Barrett’s esophagus was diagnosed 4.88 times more often than in gastric-type metaplasia of the distal esophagus. Malignant neoplasms were detected in 59 patients (32.96% of all esophageal tumors). Conclusion. Among non-neoplastic esophageal diseases, eosinophilic esophagitis was in 11.74% of cases. Complications of gastroesophageal reflux disease predominated among non-neoplastic esophageal diseases (51.24%). During histological examination, particular attention should be paid to the presence of dysplastic changes. Keywords: esophageal diseases, eosinophilic esophagitis, gastroesophageal reflux disease, Barrett’s esophagus, esophageal cance