Gastric mucosal changes caused by Lugol's iodine solution spray: endoscopic features of 64 cases on screening esophagogastroduodenoscopy

Visibility of esophageal squamous cell carcinoma under iodine staining on texture and color enhancement imaging

Objective

Iodine staining on white light imaging (WLI) is the gold standard for detecting and demarcating esophageal squamous cell carcinoma (ESCC). We examined the effects of texture and color enhancement imaging (TXI) on improving the endoscopic visibility of ESCC under iodine staining.

Methods

Twenty ESCC lesions that underwent endoscopic submucosal dissection were retrospectively included. The color difference between ESCC and the surrounding mucosa (ΔEe) on WLI, TXI, and narrow-band imaging was assessed, and ΔEe under 1% iodine staining on WLI and TXI. Furthermore, the visibility grade determined by endoscopists was evaluated on each imaging.

Result

The median ΔEe was greater on TXI than on WLI (14.53 vs. 10.71, respectively; p < 0.005). Moreover, the median ΔEe on TXI under iodine staining was greater than the median ΔEe on TXI and narrow-band imaging (39.20 vs. 14.53 vs. 16.42, respectively; p < 0.005 for both). A positive correlation in ΔEe under iodine staining was found between TXI and WLI (correlation coefficient = 0.61, p < 0.01). Moreover, ΔEe under iodine staining on TXI in each lesion was greater than the corresponding ΔEe on WLI. The visibility grade assessed by endoscopists on TXI was also significantly greater than that on WLI under iodine staining (p < 0.01).

Conclusions

The visibility of ESCC after iodine staining was greater on TXI than on WLI.

Optimal concentration of Lugol's solution for detecting early esophageal carcinoma: A randomized controlled trial

BACKGROUND AND AIM

Lugol chromoendoscopy is the standard technique to detect an esophageal squamous cell carcinoma (ESCC). However, a high concentration of Lugol's solution can induce mucosal injury and adverse events. We aimed to investigate the optimal concentration of Lugol's solution to reduce mucosal injury and adverse events without degrading image quality.

METHODS

This was a two-phase double-blind randomized controlled trial. In phase I, 200 eligible patients underwent esophagogastroduodenoscopy and then were randomly (1:1:1:1:1) sprayed with 1.2%, 1.0%, 0.8%, 0.6%, or 0.4% Lugol's solution. Image quality, gastric mucosal injury, adverse events, and operation satisfaction were compared to investigate the minimal effective concentration. In phase II, 42 cases of endoscopic mucosectomy for early ESCC were included. The patients were randomly assigned (1:1) to the minimal effective (0.6%) or conventional (1.2%) concentration of Lugol's solution for further comparison of the effectiveness.

RESULTS

In phase I, the gastric mucosal injury was significantly reduced in 0.6% group (P < 0.05). Furthermore, there was no statistical significance in image quality between 0.6% and higher concentrations of Lugol's solution (P > 0.05, respectively). It also showed that the operation satisfaction decreased in 1.2% group compared with the lower concentration groups (P < 0.05). In phase II, the complete resection rate was 100% in both groups, while 0.6% Lugol's solution showed higher operation satisfaction (W = 554.500, P = 0.005).

CONCLUSIONS

The study indicates that 0.6% might be the optimal concentration of Lugol's solution for early detection and delineation of ESCC, considering minimal mucosal injury and satisfied image. The registry of clinical trials: ClinicalTrials.gov (NCT03180944).

Acute and subchronic toxicity studies of the original drug FS-1

Interest in iodine complexes has increased significantly in recent years because of their wide spectrum of biological activity. The FS-1 is an ion nanostructured complex formed by proteins and/or polypeptides, carbohydrates, salts of alkali and alkaline earth metals with intercalated iodine. Patented in 2014, it is intended for the treatment of infectious diseases of bacterial origin including nosocomial infections and multidrug resistant tuberculosis. The aim of the study was to determine its acute and subchronic toxicity. The study of acute and subchronic toxicity was performed on adult Wistar rats according to OECD guidelines. The data on acute toxicity showed LD50 > 2,000 mg/kg after a single intragastric administration. Twenty-eight days of FS-1 administration at a dose of 500 mg/kg resulted in toxic effects. At a dose of 250 mg/kg, the toxic effects were temporary and a return to normal followed after the recovery period. Doses of 100 mg/kg had no adverse effects on the rats.

Effects of Lugol staining on stenosis formation induced by radiofrequency ablation of esophageal squamous epithelium: a study in a porcine model

Preliminary data show higher stricture rates after radiofrequency ablation (RFA) for early esophageal squamous neoplasia compared with Barrett's esophagus. We studied the effects of Lugol stain (LS) directly prior to RFA on stricture formation in squamous epithelium. Of 16 pigs, the distal half of the esophagus was LS, followed by circumferential RFA (single application 12 J/cm(2) ) in the unstained and stained esophagus. Pigs were euthanized at day 0 (n = 4), 3 (n = 4), or 28 (n = 8). Histology was evaluated in four areas: blank-control (no RFA, no LS), blank-RFA (no LS), LS+RFA, and LS-control (no RFA). Stenosis severity in LS+RFA and blank-RFA at 28 days was assessed by the ratio of the mucosal diameter at the RFA area to the diameter 2 cm proximal of this zone. Histology showed submucosal edema in 50% of LS+RFA versus 0% in blank-RFA. Severity and depth of inflammation (day 3) was equal in LS+RFA and blank-RFA. Severity and depth of fibrosis (day 28) appeared more severe in LS+RFA. Consequently, stenosis was present in 100% (LS+RFA) versus 12.5% (blank-RFA). The stenosis-severity ratio was 0.40 (interquartile range 0.29-0.45) in LS+RFA versus 0.73 (interquartile range 0.64-0.78) in blank-RFA (P = 0.012). Limitations of this study were the difference in uptake of LS between pigs and humans, the difference in esophageal anatomy between pigs and humans, and between the proximal and distal esophagus within pigs. In conclusion, in the porcine squamous esophagus, stenosis rate and severity after RFA increased when preceded by LS. LS may be contributing in the altered response of squamous epithelium to RFA as compared with Barrett's esophagus.