This is a retrospective study to evaluate the prevention of complications of metallic stent placement in patients with unresectable advanced esophageal cancer. A total of 87 patients were treated with 4 types of metal stents in the esophagus over a period of 18 years. Stent placement was technically successful. The most common prior treatment was chemoradiotherapy. There were no significant differences in the rate of patients with no complications among the prior treatments. Approximately, 30% of patients had the most common chest pain in complications. Stent placement within one month after the completion of chemoradiotherapy should be avoided for the prevention of the chest pain. There was no significant difference in the rate of patients with no complications by lesion location. The rate of no complications was higher for the Niti-S stent than the Gianturco Z-stent or Ultraflex stent. Of note, no complications were noted for the Niti-S ultrathin stent at all. Among cases of stent-related death, the most common type of complication was respiratory disorder caused by the stent that seems to be thick and hard. Therefore, the stent with thin and flexible characteristics like the Niti-S ultrathin stent will solve the various problems of esophageal stent placement.
Self-expandable metallic stent (SEMS) placement is used widely for the palliative treatment of unresectable malignant esophageal stricture [
We have placed SEMSs in patients with esophageal cancer over a period of approximately 20 years. Therefore, we examined their data, retrospectively, and would like to recommend the prevention of complications based on many experiences of metallic stent placement in patients with unresectable esophageal cancer.
A total of 87 patients were treated with a metal stent in the esophagus from December 1997 to April 2015 at the Chiba University Graduate School of Medicine. Data from these patients were collected retrospectively. The poststented follow-up period was ranged 2–153 days, mean 59.3 days, and median 52 days. A tumor was considered inoperable if the patient had distant metastasis, local tumor infiltration in neighboring organs, or a poor health condition. The expected average prognosis was around three months. We excluded patients who were scheduled to undergo future treatment, were not expected to be able to eat again, had recurrent nerve paralysis, or had a tumor growth within 2 cm of the upper esophageal sphincter. Furthermore, because the esophagus after stent insertion does not move peristaltically, we excluded any patients who were unable to sit up.
All patients were evaluated before stent placement and at discharge. Furthermore, we performed evaluations by interviewing the patients’ family about the following items: (1) ability to eat and/or swallow (graded as 0, normal swallowing; 1, able to swallow some but not all solids; 2, able to swallow semisolids; 3, able to swallow fluids only; 4, unable to swallow fluids [
During stent insertion, all patients were consciously sedated with midazolam and pentazocine. The upper tumor margin was marked with an endoscopic hemoclip confirmed by radioscopy. A guidewire was inserted into the esophagus. A catheter for endoscopic retrograde cholangiopancreatography was inserted over the guidewire. The length of stricture was measured under radioscopy. The stents were advanced over the guidewire into the esophagus. The stricture was never dilated with a dilator such as a balloon. If the delivery system of the stent was unable to pass the tumor, the stent was covered with a polyvinyl chloride tube to make the axis stronger.
Four types of stent were used. We actually confirmed the feel of many kinds of stents released, and the tenderest stent was chosen in the time. The characteristics of the Gianturco Z-stent (Z stent), Ultraflex stent (UF stent), Niti-S stent (NS stent) (Figure
Partially covered Niti-S stent (Taewoong Medical) 10 cm long with a diameter of 16 mm. The partially covered stent is uncovered at both ends over a distance of 0.5 cm. This stent is able to maintain a three-dimensional form.
Fully covered Niti-S ultrathin stent (Taewoong Medical) 10 cm long with diameters of 12 mm (proximal) and 10 mm (middle-distal).
Self-expandable metallic stent characteristics.
Characteristics | Gianturco Z-stent | Ultraflex stent | Niti-S stent |
---|---|---|---|
Products | Cook Medical Co., Denmark | Boston Scientific Co., Ireland | Taewoong Medical Co., Korea |
Material | Stainless | Nitinol | Nitinol |
Membrane material | Polyethylene | Polyethylene | Polytetrafluoroethylene |
Outside diameter (mm) | 18 | 17 | 18, 16, 10 (NSu stent) |
Major axis (mm) | 100, 120, 140 | 100, 150 | 80, 100, 120, 150 |
Delivery system diameter (Fr) | 24 | 24 | 16.5 |
Shortening (%) | None | 70 | 70 |
Softness | − | ++ | +++ |
Extended force | +++ | ++ | + |
Visibility | Good | Good | Good |
Justification | Impossible | Possible | Possible |
Removed | Impossible | Possible within 2 weeks | Possible within 2 weeks |
+: mild; ++: moderate; +++: severe.
Fisher’s exact test was used to evaluate the differences in the proportions between the groups after chemoradiotherapy (CRT). The statistical analyses were conducted using the SPSS 15.0 software package (SPSS Inc., Chicago, IL, USA).
The patient characteristics are outlined in Table
Patient and tumor characteristics.
Characteristics | |
---|---|
Gender ( | |
Male | 79 |
Female | 8 |
Age ( |
|
Range | 39–87 |
Median | 66.9 |
Tumor site ( | |
Ce, Ut | 12 |
Mt | 47 |
Lt, Ae | 28 |
Prior treatment※ | |
None | 14 |
CRT | 51 |
RT | 1 |
CT | 23 |
Others | 16 |
Reason for unresection※ | |
T4※※ | 45 |
N3, N4※※ | 24 |
M1※※ | 18 |
Poor condition | 23 |
Rejection | 1 |
Reason for insertion | |
Stenosis | 63 |
Fistula | 24 |
Ce: cervical esophagus; Ut: upper thoracic esophagus; Mt: middle thoracic esophagus; Lt: lower thoracic esophagus; Ae: abdominal esophagus; CRT: chemoradiotherapy; RT: radiotherapy; CT: chemotherapy. ※There is some overlap; ※※Japanese Classification of Esophageal Cancer [
The changes in the oral alimentation status of the patients are shown by dysphagia score in Table
Improvement in the dysphagia score (mean ± SD).
Stent | Number of times | Prescore | Postscore | Improvement score |
---|---|---|---|---|
Z | 17 | 3.65 ± 0.49 | 2.35 ± 1.22 | 1.3 |
UF | 53 | 3.21 ± 0.95 | 1.45 ± 1.2 | 1.76 |
NS | 18 | 4 ± 0.57 | 2 ± 1.11 | 2 |
NSu | 3 | 4 | 2.67 ± 0.58 | 1.33 |
Total | 91 | 3.43 ± 0.82 | 1.79 ± 1.25 | 1.64 |
Z: Cook-Z stent; UF: Ultraflex stent; NS: Niti-S stent; NSu: Niti-S ultrathin stent; Improvement score = prescore minus postscore.
Relationships between complications and prior treatment (
None |
CRT※ |
RT |
CT※ |
Others※ |
|
---|---|---|---|---|---|
Chest pain※ | 2 (15.4) | 15 (29.4) | 1 (100) | 8 (34.8) | 4 (25.0) |
Nausea※ | 0 | 1 (2.0) | 0 | 1 (4.3) | 0 |
Hiccup※ | 0 | 1 (2.0) | 0 | 1 (4.3) | 0 |
Gastroesophageal reflux※ | 2 (15.4) | 0 | 0 | 2 (8.7) | 0 |
Recurrent dysphagia※ | 2 (15.4) | 1 (2.0) | 0 | 1 (4.3) | 1 (6.3) |
Stent migration※ | 0 | 1 (2.0) | 0 | 0 | 0 |
Hemorrhaging※ | 0 | 0 | 0 | 1 (4.3) | 0 |
Perforation※ | 1 (7.7) | 1 (2.0) | 0 | 0 | 0 |
Airway narrowing※ | 1 (7.7) | 0 | 0 | 0 | 1 (6.3) |
Aspiration pneumonia※ | 0 | 0 | 0 | 1 (4.3) | 0 |
Respiratory failure※ | 1 (7.7) | 1 (2.0) | 0 | 0 | 0 |
None | 6 (46.2) | 27 (52.9) | 0 | 13 (56.5) | 9 (56.3) |
CRT: chemoradiotherapy; RT: radiotherapy; CT: chemotherapy. ※There is some overlap.
Relationships of the chest pain and the period from chemoradiotherapy (60 Gy) completion to stent insertion (
Period from CRT to insertion (days) | 1–30 | 31–60 | 61 and above |
---|---|---|---|
Gender | |||
Male | 6 | 4 | 10 |
Female | 0 | 0 | 0 |
Age | |||
Median | 64.8 | 64.6 | 65.9 |
Tumor location | |||
Ce, Ut | 2 | 0 | 2 |
Mt | 3 | 3 | 5 |
Lt, Ae | 1 | 1 | 3 |
Reason for intubation | |||
Stenosis | 5 | 2 | 7 |
Fistula | 1 | 2 | 3 |
Type of SEMS | |||
Z | 2 | 1 | 1 |
UF | 4 | 3 | 8 |
NS | 0 | 0 | 1 |
Chest pain (%) | 5/6 (83.3) |
2/4 (50.0) | 3/10 (30.0) |
CRT: chemoradiotherapy; Ce: cervical esophagus; Ut: upper thoracic esophagus; Mt: middle thoracic esophagus; Lt: lower thoracic esophagus; Ae: abdominal esophagus; Z: Cook-Z stent; UF: Ultraflex stent; NS: Niti-S stent;
Relationships of complications and lesion location (
Ce, Ut |
Mt |
Lt, Ae |
|
---|---|---|---|
Chest pain※ | 4 (33.3) | 16 (32.0) | 8 (27.6) |
Nausea※ | 0 | 2 (4.0) | 0 |
Hiccup※ | 2 (16.7) | 0 | 0 |
Gastroesophageal reflux※ | 1 (8.3) | 4 (8.0) | 5 (17.2) |
Recurrent dysphagia※ | 0 | 4 (8.0) | 1 (3.4) |
Stent migration※ | 0 | 0 | 1 (3.4) |
Hemorrhage※ | 0 | 1 (2.0) | 0 |
Perforation※ | 0 | 1 (2.0) | 1 (3.4) |
Airway narrowing※ | 1 (16.7) | 1 (2.0) | 0 |
Aspiration pneumonia※ | 0 | 0 | 1 (3.4) |
Respiratory failure※ | 0 | 2 (4.0) | 0 |
None | 6 (50.0) | 27 (54.0) | 14 (48.3) |
Ce: cervical esophagus; Ut: upper thoracic esophagus; Mt: middle thoracic esophagus; Lt: lower thoracic esophagus; Ae: abdominal esophagus. ※There is some overlap.
Relationships of complications and types of SEMS (
Z |
UF |
NS |
NSu |
|
---|---|---|---|---|
Chest pain※ | 6 (35.3) | 20 (37.7) | 2 (11.1) | 0 |
Nausea※ | 0 | 2 (3.8) | 0 | 0 |
Hiccup※ | 0 | 2 (3.8) | 0 | 0 |
Gastroesophageal reflux※ | 2 (11.8) | 8 (15.1) | 0 | 0 |
Recurrent dysphagia※ | 0 | 4 (7.5) | 1 (5.6) | 0 |
Stent migration※ | 1 (5.9) | 0 | 0 | 0 |
Hemorrhaging※ | 0 | 1 (1.9) | 0 | 0 |
Perforation※ | 1 (5.9) | 0 | 1 (5.6) | 0 |
Airway narrowing※ | 0 | 3 (5.7) | 0 | 0 |
Aspiration pneumonia※ | 0 | 1 (1.9) | 0 | 0 |
Respiratory failure※ | 2 (11.8) | 0 | 0 | 0 |
None | 7 (41.2) | 23 (43.4) | 14 (77.8) | 3 (100) |
Z: Cook-Z stent; UF: Ultraflex stent; NS: Niti-S stent; NSu: Niti-S ultrathin stent. ※There is some overlap.
Stent-related fatal cases.
Age (years) | Gender | Location | T4 | Reason for insertion | Type of SEMS | Pretreatment | Periods to complication | Complications | Periods from insertion to death (days) |
---|---|---|---|---|---|---|---|---|---|
85 | Male | Mt, Lt | None | Stenosis | Z | None | During insertion | Perforation | 2 |
49 | Female | Mt | None | Stenosis | Z | CRT (40 Gy) | 8 hours | Respiratory failure | 6 |
68 | Male | Lt, Ae | None | Stenosis | UF | CT | 1 day | Aspiration pneumonia | 22 |
81 | Male | Ce | Trachea | Stenosis | UF | CRT (65 Gy), GT | 3 days | Airway narrowing | 25 |
61 | Male | Ut, Mt | Trachea | Fistula | UF | None | 15 days | Airway narrowing | 22 |
Ce: cervical esophagus; Ut: upper thoracic esophagus; Mt: middle thoracic esophagus; Lt: lower thoracic esophagus; Ae: abdominal esophagus; Z: Cook-Z stent; UF: Ultraflex stent; CRT: chemoradiotherapy; CT: chemotherapy; GT: genetherapy.
Although this study is retrospective, a lot of countermeasures have been revealed for safe and effective esophageal stent placement. Stent placement within one month after the completion of CRT should be avoided for the prevention of the chest pain. Death soon after stent placement had a strong relationship with respiratory complications. To prevent such complications, an ultrathin stent might be best.
SEMS placement is used widely for the palliative treatment of unresectable malignant esophageal stricture [
The stent-related deaths occurred in patients who died within one month after insertion. All cases including a patient that occurred pneumothorax after esophageal perforation had respiratory disorders. Two patients who had complications just after stent insertion used the Z stent with high radial and axial forces. Moreover, two cases using Z stent suffered from respiratory failure. The rapid increase of the right pleural effusion was pointed out. Therefore, there may have been damage to the thoracic duct. Generally, stents with strong expansion and a wide lumen are deemed suitable. However, such stents can cause many severe complications [
(a) CT findings before stent placement. Two months after chemoradiotherapy, the tumor located in the middle thoracic esophagus had invaded the trachea. (b) CT findings after Niti-S ultrathin stent placement (arrow). The membranous portion of the trachea did not transform (arrowhead).
It might be very important not to dilate the stenosis using a balloon before stent insertion. When an esophageal stent is inserted, such as a UF stent, prior dilation is generally performed with a 10 to 18 mm balloon [
Regardless of previous treatment, about 50% of patients who underwent esophageal stent placement suffered complications in our study. The use of SEMSs in patients with prior RT is strictly limited [
This study has several limitations. It was a retrospective study performed in a single institution. The stent placement was done for only patients with a prognosis of three months or less. In an additional investigation, 63.2% (55/87) of patients could be followed and the 3-month survival rate was 34.5% (19/55). We believe that the expected prognosis was not significantly different from the reality. However, the applications of esophageal SEMS placement should be further clarified in large, prospective studies.
In this study, a lot of problems associated with metallic stents in patients with unresectable advanced esophageal cancer were revealed. However, we suggest that the stent with thin and flexible characteristics like the Niti-S ultrathin stent will solve the various problems of esophageal stent placement. If the stent placement in patients with prior CRT is performed, the placement within one month after the completion of CRT should be avoided for the prevention of the chest pain.
Self-expandable metallic stent
Radiotherapy
Gianturco Z-stent
Ultraflex stent
Niti-S stent
Niti-S ultrathin stent
Chemoradiotherapy.
Patients were not required to give their informed consent for the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment with their written consent.
The authors declare no conflicts of interest for this article.