Iyer, P. K. R.

Abstract Topic Benign Disease: Other Background Lichen planus is a chronic immune-mediated skin disease that may involve the esophagus. Esophageal lichen planus (ELP) is considered rare, but likely underdiagnosed. Lack of published guidelines for ELP results in significant treatment variability. Given heterogeneous practice patterns and emerging treatments, further outcome data are needed. Methods A retrospective cohort of ELP patients was assembled from 3 academic centers. Patients ≥ 18 years old were identified by ICD10 code search (L43.8) in the electronic health record, from 2006 to 2025. Patients were included if they had initial endoscopy, histology, and follow-up endoscopy showing features of LP, and excluded if there was diagnostic uncertainty, unavailable procedural documentation, or other esophageal diseases. Endoscopic findings were assessed qualitatively by manual review of reports. Data abstracted included demographics, presenting symptoms, endoscopic/histologic findings, treatment, and clinical outcomes. Statistical analysis was performed in R. Results 193 patients met inclusion criteria. Mean age at index endoscopy was 65 years, 86% were female, 98% were non-Hispanic Caucasian, 39% were ever smokers, and mean BMI was 26. Dysphagia was the most common presenting symptom (90%). Strictures were common (73%), 58% underwent dilation during initial endoscopy. Endoscopic findings included presence of sloughing (20%), exudate (22%) and friability (23%). Histology showed lymphocytic infiltrate (47%), parakeratosis/dyskeratosis (42%) and Civatte bodies (17%). Topical steroids (71%) and PPIs (63%) were used most frequently for treatment. Immunosuppressives (tacrolimus, systemic steroids, mycophenolate, methotrexate, hydroxychloroquine, cyclosporine, azathioprine, JAK inhibitor) were used in 54% of patients. Endoscopic improvement was seen in 66%, with highest response rates in tacrolimus (100%), hydroxychloroquine (100%), and a JAK inhibitor (100%). Symptom improvement was seen in 63%, with the greatest benefit seen in patients treated with a JAK inhibitor (100%) and hydroxychloroquine (86%). Conclusion In this large, multisite cohort, ELP demonstrated significant morbidity, with high rates of dysphagia, strictures, and inflammatory changes. Dilation appeared to be safe, with only a single iatrogenic perforation identified. Esophageal squamous cell cancer risk was low but present, at 4%. Despite heterogeneous treatment practices, several therapies – tacrolimus, hydroxychloroquine, and JAK inhibitors – were associated with marked endoscopic and symptomatic improvement. Prospective studies are needed to clarify the optimal approach to pharmacological management of ELP.

Introduction Visceral obesity is associated with GERD and, traditionally, it has been assumed that visceral fat predisposes to GERD primarily by increasing intra‐abdominal pressure. However, transmission electron microscopy (TEM) of esophageal biopsies from obese individuals without GERD exhibit dilated intercellular spaces (DIS) and, in earlier studies, we found that substances secreted by mature adipocytes in visceral fat from obese patients impair esophageal epithelial barrier function, induce DIS and reduce transepithelial resistance (TER). There is a fat pad at the gastroesophageal junction (GEJ) that is in intimate contact with the distal esophagus. We now explore whether whole GEJ fat tissue of obese individuals secretes substances that impair esophageal barrier function. Methods We obtained GEJ fat from 3 obese (BMI 46, 60, 74) and 3 non‐obese (BMI 24, 26, 27) patients having foregut surgery. Human esophageal squamous cells were seeded into transwells and grown to confluence for 3 days. On day 4, cells were raised to an air‐liquid interface (ALI) to allow for differentiation, stratification, and esophageal barrier formation. ALI cultures were exposed to conditioned media (CM) from GEJ fat or to control medium beginning at day 4. TER was measured on days 4, 6, and 8 using the EVOM2 Epithelial Volt/Ohm Meter. On day 8, ALI cultures were stained with H&E and Ki‐67 and imaged; barrier permeability was assessed by a biotinylation reagent applied to the ALI surface. TEM of ALIs and of esophageal biopsies from 2 non‐obese and 2 obese patients without GERD were assessed. Results CM from all 3 obese patients significantly reduced TER on days 6 and 8; CM from 2 non‐obese patients did not reduce TER whereas CM from 1 non‐obese patient induced a slight reduction in TER at day 8 (Table 1). Marked DIS were found only in ALI cultures grown with CM from obese patients. In ALIs grown with CM from non‐obese patients, the biotinylation reagent stopped at the superficial layers of esophageal cells. In contrast, the biotinylation reagent diffused through all cell layers in ALIs grown with obese patient CM. Increases in basaloid cells and in Ki‐67 were found in ALIs grown with obese patient CM. TEMs of ALIs grown with non‐obese patient CM demonstrated well‐oriented cell‐cell junctions similar to TEMs of non‐obese patient esophageal biopsies. In contrast, ALIs grown with obese patient CM demonstrated cell‐cell junctional structures that were disorganized, aggregated, and floating within the DIS, similar in appearance to TEMs of the obese patients’ esophageal biopsies. Conclusion Substances produced by GEJ fat of obese patients impair esophageal epithelial barrier integrity, cause basal cell hyperplasia and DIS, and disrupt intercellular connections. These findings in ALI cultures recapitulate abnormalities seen by TEM in esophageal biopsies of obese patients.

Abstract Background The neo-squamous epithelium that replaces columnar epithelium after successful endoscopic ablation of Barrett's esophagus (BE) has not been fully characterized in regard to its structural and functional integrity. Intercellular space is a surrogate marker for epithelial structural integrity and mucosal impedance (MI) is a surrogate for transepithelial resistance and thus epithelial functional integrity. Impairment of the structural and functional integrity may influence recurrence following successful ablation. We aimed to measure the esophageal epithelial intercellular space diameter and MI in the neo-squamous and normal squamous epithelium of patients who underwent successful radiofrequency ablation for dysplastic BE. Methods Forty patients with complete remission of intestinal metaplasia (CRIM) (defined as two negative surveillance endoscopies for intestinal metaplasia) were prospectively recruited. Patients were excluded if they had endoscopic evidence of esophagitis. MI measurements were taken at 1 cm above the GE junction and 2 cm above the prior BE segment (targeting uninvolved squamous epithelium), using a novel through the scope MI probe. Endoscopic biopsies were also taken at these corresponding sites to assess intercellular space diameter using transmission electron microscopy (TEM) using standard techniques. Results 80% of patients were male with a mean age of 69 years. Mean follow since achieving CRIM was 30 months. 39 patients underwent RFA for dysplasia. The mean intercellular space diameter was higher in the neo-squamous epithelium (1.01 μm) when compared to the untreated native squamous epithelium (0.96 μm) [Difference of 0.056 μm, 95% CI of -0.036 to 0.148, P = 0.228]. The mean MI was significantly lower in the neosquamous epithelium (4001.3 Ω) when compared to the untreated native epithelium (5168.1 Ω) [Difference of 1166.7 Ω, 95% CI 418.8 to 1914.6, P = 0.003]. Conclusion Neo-squamous epithelium that replaces BE epithelium following successful endoscopic therapy for BE appears to be functionally and likely structurally deficient with regards to acid reflux barrier function, when compared to native squamous esophageal epithelium. This impairment may be associated with recurrence following successful ablation. Disclosure All authors have declared no conflicts of interest.