Endoscopic ultrasound in esophageal obstructing tumors

Amir Hasanvand,1,* Zeynab yaberi mohammad,2

1. Department of Radiologic Technology, Faculty of Paramedicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
2. Department of Radiologic Technology, Faculty of Paramedicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

Abstract

Introduction

It is not uncommon for the endosonographer to encounter an obstructing esophageal cancer that prevents the passage of the ultrasound scope. in fact, up to one-third of patients who present with esophageal cancer will have luminal stenosis to the degree passage of a 12–13 mm endoscope is prevented. there are several options the endoscopist may entertain to overcome this challenge. one is to position the echoendoscope tip at a position proximal to the tumor and perform the examination from here. accuracy is significantly reduced by this method, and evaluation of distal lymph nodes – such as the celiac nodes – may be impossible. however, this practice often reveals at least a t3 disease, which can have an important impact on management strategy.

Methods

Publications were retrieved by a systematic search of multiple bibliographic databases, including medline, embase, scopus, cochrane library, web of science, biomed central, science direct, and google scholar. the language of search was restricted to english.

Results

. endoscopic dilation of the stricture to allow scope passage is an additional option. this can be done using a through-the-scope balloon dilator or savory bougienage over a wire. dilation to at least 15 mm is usually required to facilitate scope passage. studies in the past associated malignant esophageal stricture dilation with a rate of perforation approaching 24%. more recent studies, however, have shown a much lower rate of perforation, specifically when careful gradual serial dilation is performed and “the rule of threes” is employed. an important consideration to keep in mind is whether or not dilating the stricture to allow scope passage will change the overall management of the patient (and whether subjecting them to the risks of dilation is worthwhile). studies have shown that roughly 90% of obstructing tumors will be t3 disease or higher. thus, the majority of these patients will be allocated to neoadjuvant chemoradiation rather than direct esophagectomy, regardless of whether lymphadenopathy is detected distal to the lesion. a third option for the staging of obstructing strictures is via the use of small-caliber hfcps or miniprobes. the small diameter of these probes may permit their passage through a stenotic tumor and provide additional staging information. they are not as effective in thicker tumors or for n-staging, and are not as routinely used in clinical practice. similarly, a small-caliber curvilinear echoendoscope used for endobronchial ultrasonography (ebus) can also be considered for use in stenotic tumors.

Conclusion

Mostly, the tumor is clearly at least t3 or n1 from even incomplete ultrasound imaging, or else advanced disease is present on cross-sectional imaging. a linear eus scope can be especially helpful in stenotic tumors, as the tip can be deflected away to obtain more longitudinal imaging from the proximal aspect, in order to more accurately assess whether the lesion invades through the muscularis propria (t3).

Keywords

Endoscopic ultrasound, esophageal tumors, indication