Postoperative non-anastomotic stenosis of the proximal jejunum after total gastrectomy with R-Y reconstruction is a rare complication. Early non-anastomotic stenosis within the first 30 postoperative days after reconstructive surgery can be caused by technical problems such as kinking, narrowing or acute angulation of the anastomosis, or internal herniation of the esophageal hiatus, while late non-anastomotic stenosis (occurring after > 1 year) can occur secondary to intra-abdominal adhesions, kinking, osmotic or ischemic changes of the proximal jejunum, or recurrence of tumors.
Recurrence of gastric cancer was ruled out based on results of blood tests and various image findings.
EBD was performed several times, and symptoms improved after EBD in the early days, but restenosis occurred within a week and proved difficult to treat.
Recently, endoscopic or fluoroscopic balloon dilation has been shown to offer a feasible procedure to avoid re-operation for non-anastomotic stenosis of the proximal jejunum. Tsauo et al. suggested that 82.1% of patients achieved clinical success after a single fluoroscopic balloon dilation, but 26.5% of patients experienced recurrence within 1 year after fluoroscopic balloon dilation . In another study, recurrence of symptoms of non-anastomotic stricture of the proximal jejunum occurred after 64.7% (11/17) of procedures .
Endoscopic and/or fluoroscopic SEMS placement is the first-line palliative option for esophageal and gastrointestinal stenosis, alternative to balloon dilation. Bakheet et al. suggested that fluoroscopic SEMS placement may be effective and safe for treating postoperative non-anastomotic strictures, but stent malfunction and recurrence are major drawbacks . In their study, stent malfunction occurred after 58.8% (10/17) of procedures, including six occurrences of stent migration and four of benign tissue hyperplasia. Furthermore, complications of SEMS placement include perforation or obstruction of the digestive tract [7, 8], and few studies have examined long-term outcomes of SEMS placement. This is why MCA was introduced for benign stenosis in patients who are unable to undergo surgery in our institution, if endoscopic balloon dilation proves ineffective.
MCA is a safe and unique technique for the reconstruction of complicating entericoenteric, biliobiliary, or bilioenteric anastomoses without surgical intervention.
Yamanouchi et al.  reported the first use of MCA in the 1990s and suggested a high success rate (almost 100%) and low complication rate (3.2%), including anastomotic leakage or other organ injury in 62 cases . MCA has been performed to treat complications such as stenosis of the bile duct after intraoperative bile duct injury for patients who are unable to undergo general anesthesia [10,11,12,13].
However, few reports have described the use of MCA in the gastrointestinal area. Kawabata et al. reported two cases in which MCA was applied to address gastrointestinal stenosis. One case involved anastomotic obstruction after subtotal gastrectomy, and the other involved endoscopic gastrojejunostomy for superior mesenteric artery syndrome. In those reports, the magnets measured 15 × 3 mm, and the duration until creation of complete anastomosis was 10 days each, similar to our case [14, 15].
The essential point of MCA in the current case was that EBD was performed first to place the 17.5-mm parent magnet on the anal side of the stenosis.
Confirming that restenosis had occurred, the daughter magnet was placed via nylon thread on the oral side of the membranous circumferential stenosis using esophagogastroduodenoscopy, resulting in shaving off the membrane of the scar tissue.
If the daughter magnet is adsorbed to the parent magnet just after EBD, MCA is not effective, because the adsorption area is so small that the residual membrane of the scar tissue is present. That is why the daughter magnet was placed 7 days after EBD with restenosis. During this period, we prevented the parent magnet from migrating using nylon thread attached to the daughter magnet, fixed to the cheek. EBD should be performed regularly to prevent restenosis after MCA. The rate of restenosis after MCA is reportedly about 20% . In the current case, we gradually lengthened the interval of EBD and finally judged that no further treatment was needed.
EBD alone is not effective, but MCA + EBD appears effective. This fact suggested that restenosis can be caused by the membrane of the scar tissue. Cheng et al. elucidated the mechanism of restenosis following balloon dilation of benign esophageal stenosis . The esophageal morphology was altered by balloon catheter dilation. The esophageal mucosa exhibited not only chemical burn lesions, but also lesions caused by mechanical damage. The thickened muscle layer of the esophagus was torn or broken, causing the areas of the mucosal and muscle layers of the esophagus to increase significantly in the experimental group. Up to a certain time, these new scar tissues of mucosa would further contract and cicatrize. As a result, the duct lumen was further reduced and lacked elasticity . Restenosis of the jejunum as in the current case is considered to involve the same mechanisms. Shaving off only the membrane of the scar tissue by MCA creates a new mucosa without creating further mucosal scarring.
MCA has been reported to show few complications, but anastomotic leakage, restenosis, injury to other organs, and deviation and aberration of the magnets are sometimes reported . Furthermore, MCA is not applicable for some cases, such as where the parent magnet cannot be placed on the anal side of the severe stenosis or malignant stenosis of the digestive tract is identified.
However, our experience suggests that MCA could offer an alternative procedure to avoid surgery for non-anastomotic stenosis of the proximal jejunum after total gastrectomy with R-Y reconstruction.
In conclusion, MCA could provide a feasible procedure to avoid surgery for non-anastomotic stenosis of the proximal jejunum after gastrectomy with R-Y reconstruction.