Palliation of malignant dysphagia is the mainstay of therapy in patients with incurable esophageal cancer. SEMS placement is a well-established application in this group of patients, mainly when cancer is located in the thoracic esophagus, away from the cardia and the upper esophageal sphincter (UES). Stents located through the cardia have a high migration index and often cause symptomatic reflux and those until 2 cm near the UES determine continuous discomfort.
After undergoing esophageal stent placement, patients need to modify their diet to prevent large boluses of food from becoming impacted within the stent causing immediate or late aspiration of the residues collected above. We didn't have such complications, but the patients were all instructed to sleep with the head of the bed raised and to avoid consistent solid food, as a prophylactic care.
Esophageal stent placement includes endoscopic assessment, guide wire insertion, tumor dilation, and stent deployment. Esophageal dilation is generally done prior to stent insertion; precise requirements for dilation depend on stent type.
Prior to stent placement, a complete endoscopic examination should be performed to assess the proximal and distal extent of the stricture. Dilation may be necessary as a first step to allow a complete exam, but the optimal degree of dilation prior to SEMS placement has not been established. With the current small delivery systems, it is generally recommended to dilate to at least 12 mm if possible, as we have done; under fluoroscopic guidance, the most useful and safest method to perform a stent placement [1, 2], a guide wire can be safely passed preceding dilation. The location of the tumor, at the medium third of the thoracic esophagus, in all the patients, and all those care measures mentioned above certainly guaranteed the null rate of severe complications of this series, but greater casuistic maybe will provoke inevitable unsuccessful cases.
When stenting mid-esophageal malignant strictures, as in this series, it is wise to leave the final dilator in place for 30-60 seconds to assess for respiratory compromise due to tumor displacement. If such compromise occurs, tracheal stenting to ensure airway patency should precede esophageal stent placement, what was not necessary in any of our cases. A chest X-ray was performed after stent placement to assess stent location and exclude complications. When the stent is properly positioned, the esophageal stricture induces a "waist" at the center of the stent immediately after deployment.
Procedure-related complications after stent placement, which weren't observed in this initial series, occur in 5% to 10% of patients and mainly consist of perforation, aspiration pneumonia, fever, hemorrhage, and severe pain. Minor complications, which are reported by 10% to 20% of patients, include mild retrosternal pain, as our patients reported, and GE reflux symptoms. Delayed complications and recurrent dysphagia to paste food following stent placement are important problems and have been reported to occur in 30% to 40% of patients. Delayed complications include hemorrhage, fistula formation, stent migration, tissue ingrowths or overgrowth, and food-bolus obstruction . Possibly a great part of these problems could be avoided reserving the stent to mid esophagus tumors, not completely obstructive, as in this series, avoiding endoprostheses and performing only a gastrostomy in extremely severe grade of the disease.
The decreasing diameters of delivery systems make perforation a rare occurrence, generally related to pre-stent dilation. Chest pain seems to be related to the expansible force of the stent, and generally resolves within some days, as we observed. Most patients with chest pain may be managed adequately with routine analgesics, as we did.
A retrospective study compared two different types of SEMS (uncovered and partially covered) for palliative treatment of 152 patients (uncovered 54 and partially covered 98) with inoperable malignant stenosis of the esophagus and cardia . Overall, 88% of patients with partially covered stents and 54% with uncovered stents were free of symptoms during follow-up (P < 0.0001). Although the rates of stent migration were lower in the uncovered stents group (0 vs. 10%, P = 0.03), tumor or granulation tissue ingrowths (100 vs. 53%, P < 0.0001) and restenosis causing recurrent dysphagia (37 vs. 8%, P < 0.0001) were significantly higher in the uncovered stents group.
It has now convincingly been shown that fully or partially covered metal stents, our stent choice, give better long-term palliation of malignant dysphagia than uncovered stents. The technical success rate for placement of partially or fully covered metal stents is close to 100%. Almost all patients experience rapid improvement of dysphagia within a few days , as in our initial series.
The endoscopic placement of covered SEMS is the treatment of choice for malignant esophageal fistulas. The quality of the evidence for malignant fistula closure with SEMS is moderate and the strength of the recommendation is strong (given the paucity of alternatives). When placing stents for this indication, it is imperative to assess for airway compromise during dilation. If respiratory distress occurs, tracheal stenting should be performed prior to placement of the esophageal stent. Fortunately we didn't have this problem and the complete closure of the fistula was showed in the barium swallow performed 12 h after the procedure. As a consequence, the patients had a grateful relief of the cough.
In three cases, the duration of follow-up was limited to just 4-12 weeks by occurrence of the patient's death due to cancer progression. This fact correlates with the advanced disease stage that these patients had prior to esophageal stent placement (13 cm in lenght), two of them showing an esophageal fistula to respiratory tree. It is likely that esophageal stent placement would be even more beneficial if done earlier in the disease course.
Our first experience reveals that the majority of stents certainly could be placed on an outpatient basis. The patient should be observed for 2 hours after the procedure, and if clinically stable and well receiving liquids via oral route, could be discharged to home with dietary instructions.