Introduction
Esophageal benign stenosis can be induced by a variety of reasons, such as esophageal anastomotic stenosis, gastroesophageal reflux, corrosive stenosis and radioactive injury (1). Recently, more and more studies have indicated that surgeries can also lead to benign esophageal stenosis, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) (2). Under various physical and chemical effects, activation of fibroblast proliferation enhances collagen deposition and scar formation, thus eventually leading to esophageal contracture. Clinical treatments of benign esophageal stenosis are varied, including surgery, expansion, stents and drugs (3). Most esophageal stenosis can achieve long-term relief by endoscopic distension 3 times. However, there are still some unrelieved cases that require repeated treatments, which is called refractory esophageal stricture or relapse esophageal stenosis (4). It is worth mentioning that esophageal stricture is a common complication of esophageal ESD. Particularly, esophageal stricture with >3/4 peeled lesion is more prone to postoperative stenosis. Some stenosis needs to be repeatedly expanded, which is known as the intractable narrow (5).
Currently, there are some methods that can prevent esophageal stenosis, including endoscopic balloon dilation, glucocorticoid, tissue engineering, amniotic membrane transplantation, gastric mucosa transplantation, polyglycolic acid tablets transplantation, and local injection of botulinum toxin. Prevention of esophageal stenosis with glucocorticoids has been demonstrated in several studies (2,5–11). In the present study, we explored the efficacy and safety of endoscopic balloon dilatation combined with glucocorticoid therapy on the treatment of esophageal stricture.
Discussion
The impact of esophageal stricture has been increasingly expanding with the clinical application of esophageal cancer surgery, radiotherapy and ESD and other new technologies. Esophageal stenosis dilatation includes the probe dilation and the balloon dilatation. Probe dilation was first developed dating back to the 16th century, represented by Savary-Gilliard. Balloon dilatation, performed in our study, was first proposed by Scolapio (12). Hagel et al (13) retrospectively analyzed 368 cases of esophageal stenosis from January 2002 to December 2011. A total of 8 cases experienced perforation, of which 1 patient in the probe expansion group died. The total perforated rate was 0.54% (8/1479), and the perforation rate of benign esophageal stenosis was 0.3% (3/912). The results showed that despite lower perforation rate, the balloon dilatation was much safer than that of the probe dilation, which might be explained by the stronger destructive effect of the probe. Glucocorticoids can not only inhibit the exudation of inflammatory cells, granulation tissue proliferation and submucosal tissue fibrosis, but also attenuate the activation and migration of inflammatory cells and fibroblasts, reduce the collagen synthesis and collagen degradation, and finally inhibit the esophageal stenosis after the expansion of scar formation (14). In this study, local injection of triamcinolone acetonide was introduced to reduce the scar formation after esophageal balloon dilatation.
It has been reported that steroid combined with endoscopic distension is applied in esophageal benign stenosis (15,16). The application of endoscopic dilation and submucosal injection of triamcinolone acetonide in the treatment of benign esophageal stenosis also achieved better curative effect. However, some studies have found that the effect of the combination treatment may be related to the stenosis extent.
Our data showed that all patients had significant improvement in swallowing and dilated symptoms at the end of treatment. The combination treatment group showed a better relief compared to that of the control group at 15 days and 1 month after operation, but the difference was not statistically significant. However, the degree of esophageal stenosis in the treatment group at 2 and 4 months after treatment was significantly better than that of the control group, the difference was statistically significant. The recurrence time of treatment group was significantly longer than that of control group, indicating that hormone treatment combined with balloon dilatation had a better effect than that of simple esophageal dilation treatment. Long-term prognosis achieved the same result. The incidence of short-term restenosis after endoscopic dilatation was higher in the control group than that of the treatment group, suggesting that endoscopic balloon dilation and submucosal triamcinolone acetonide injection could prolong the short-term restenosis of esophagus and reduce the incidence rate of recent restenosis.
In addition, the injection of triamcinolone acetonide after endoscopic dilation could effectively reduce tissue damage, inflammatory exudation and inflammatory cell aggregation, inhibit fibroblast activity, and finally reduce or alleviate the forming of scars. The specific mechanisms, however, need to be further clarified. Clinical evidence also revealed that the expansion extent is positively correlated with recurrence time of esophageal stricture (17–19), which was consistent with our findings. In our study, the recurrence time of esophageal stricture in the <16-mm subgroup was significantly shorter than that in the expanded >16-mm subgroup.
In this study, no patient had mediastinal emphysema, esophageal abscess, esophageal perforation and other complications, indicating that the degree of balloon expansion may not be associated with the risk of esophageal perforation, which was consistent with other researches (17,20).
In conclusion, our study showed that endoscopic balloon dilatation combined with local injection of triamcinolone acetonide in the treatment of benign esophageal stenosis is superior to the simple balloon dilatation, which significantly prolongs esophageal restenosis and reduces the duration of esophageal dilatation. In addition, the effect of the combination therapy is better when the degree of balloon dilatation is >16 mm.