Infolding of Ultraflex self-expanding metal stent on insertion

Inhaltsübersicht

Esophageal cancer is often diagnosed at an advanced stage, without curative options in 50 % – 60 % of cases. Of the major complications, the principal ones are luminal obstruction and esophagorespiratory fistulas [1].

Among palliative measures, self-expanding metal stents (SEMS) have provided good quality of life for patients and are cost-effective [2]. Despite these advantages, the use of SEMS is not free of complications, namely incomplete expansion, migration, perforation, hemorrhage, tracheal compression, or food impaction [1].

Recently some authors have demonstrated accurate and safe stenting using only endoscopic guidance, without fluoroscopic support [3] [4].

The Ultraflex stent has been associated with more occurrences of incomplete expansion and migration as well as infolding after deployment, as its construction favors a smaller radial force; thus, whilst preventing the risk of major trauma, it occasionally requires balloon dilation [5].

We report an unusual event after insertion of a covered 12-cm Ultraflex SEMS under sedation and without fluoroscopic control. The patient was a 52-year-old man with inoperable lower third esophageal cancer, who had previously undergone chemotherapy and radiotherapy and currently had grade 3 dysphagia ([Fig. 1]).

After deployment the stent adopted a bizarre ”B type“ infolded conformation with maintenance of double lumen patency ( [Fig. 2] and [3]), whilst successfully covering the fistula holes. After 24 hours, repeat endoscopy revealed the same findings. Balloon dilation was done unsuccessfully. Biopsy rat-tooth forceps were used to displace the stent, which allowed it to unfold but uncovered the fistula opening ([Fig. 4]). A second attempt, using the same instrument, correctly positioned the prosthesis ([Fig. 5] and [6]).

Fig. 1 Esophagorespiratory fistula.

Fig. 2 Endoscopic view of infolded stent.

Fig. 3 Radiographic view of infolded stent.

Fig. 4 The uncovered opening of the fistula.

Fig. 5 Endoscopic confirmation of correct opening of the stent.

Fig. 6 Esophagographic confirmation of correct opening of the stent.

The patient remained asymptomatic for the following 6 months and required no further endoscopic examinations.

This report highlights a possible and previously unconsidered adverse event, and is a reminder of the importance of improvisation and of the necessity for improvements in stent design.

Endoscopy_UCTN_Code_CPL_1AH_2AD

References

• 1 Wang M Q, Sze D Y, Wang Z P. et al . Delayed complications after esophageal stent placement for treatment of malignant esophageal obstructions and esophagorespiratory fistulas.  J Vasc Interv Radiol. 2001;  12 465-474
• 2 Knyrim K, Wagner H J, Bethge N. et al . A controlled trial of an expansile metal stent for palliation of esophageal obstruction due to inoperable cancer.  N Engl J Med. 1993;  329 1302-1307
• 3 Singhavi R, Abbasakor F, Manson J McK. Insertion of self-expanding metal stents for malignant dysphagia: assessment of a simple endoscopic method.  Ann R Coll Surg Engl. 2000;  82 243-248
• 4 White R E, Mungatana C, Topazian M. Esophageal stent placement without fluoroscopy.  Gastrointest Endosc. 2001;  53 348-351
• 5 Nevitt A W, Kozarek R A, Kidd R. Expandable esophageal prostheses: recognition, insertion techniques, and positioning.  AJR Am J Roentgenol. 1996;  167 1009-1013