A 33-year-old patient presented with recurrent vomiting, abdominal pain, and jaundice. The patient had undergone pylorus- preserving pancreaticoduodenectomy to treat pancreatic head cancer 13 months prior and had received concurrent chemoradiotherapy until recently. The laboratory findings included elevated carbohydrate antigen 19-9 (7,460 U/mL) and bilirubin (9.7 mg/dL) levels suggestive of tumor recurrence. Abdominal computed tomography (CT) revealed severe dilatation of the afferent (A-) loop (black arrows) with some retained food material (white arrow) in the remnant stomach and multiple hepatic abscesses in both lobes attributable to stricture of the previous surgical anastomosis site (Fig. 1A, B). Endoscopy revealed severe ulcerative changes (with obstruction) near the anastomosis site, suggestive of tumor recurrence (left lower corner of Fig. 1C). We inserted two 8 × 22 mm uncovered metal stents (Niti-S, D-type; Taewoong Medical, Seoul, Korea) (arrow) into the A-loop and (in parallel) the efferent (E-) loop (right lower corner) to relieve the stricture near the anastomosis site (Fig. 1C). The symptoms were much improved. However, residual dyspepsia with inadequate resolution of liver function (including an elevated bilirubin level; 5.3 mg/dL) persisted until 7 days after insertion. Another insertion of a 3 cm × 10 mm LAMS (Niti-S SPAXUS; Taewoong Medical) into the proximal site of the A-loop was thus performed. The procedural steps included (in order) identification of the puncture site under EUS guidance, confirmation of the location via injection of contrast, tract dilation with a cystotome and a 4-6 mm balloon dilator, and stent deployment (left lower corner) (Fig. 1D). The residual symptom (jaundice) then improved rapidly. Follow-up CT revealed that the A-loop dilatation and liver abscess had greatly improved. However, the patient revisited us with recurrent vomiting and dyspepsia at 5 months after discharge. Abdominal CT revealed stomach dilatation but no obvious A-loop dilatation suggestive of obstruction caused by tumor ingrowth at the surgical anastomosis site (thus, E-loop stenosis) (Fig. 1E, F). Endoscopy revealed large amounts of retained gastric fluid and food material in the remnant stomach (left lower corner of Fig. 1E). Only the gastrojejunostomy stent (inserted via EUS) in the proximal A-loop was clearly visible (right lower corner of Fig. 1E). The two other stents (in the A-loop and the anastomosis site of the E-loop) were deeply embedded, collapsed proximally, and clogged with food residue (right lower corner in Fig. 1F). After guidewire manipulation, another overlapping 8 cm × 22 mm uncovered metal stent (Niti-S, D-type; Taewoong Medical) was inserted through the previous stent into the E-loop side, whereupon the symptoms improved markedly. However, the patient revisited us with similar symptoms at 3 months after the second discharge. We recommended surgery but the patient declined. We performed EUS-guided gastrojejunostomy (left upper corner) and placed a 3 cm × 16 mm LAMS (Niti-S SPAXUS; Taewoong Medical) (arrow, right lower corner) into the distal site on the E-loop side (arrowheads) under the guidance of previously inserted overlapping metal stents (Fig. 1G). The new LAMS was appropriately inserted, as revealed by endoscopic and CT images (Fig. 1H). The symptoms improved markedly. The patient was discharged 5 days later. No further digestive symptoms were observed until death attributable to malignant disease progression 5 months later (despite chemotherapy).

A 55-year-old male underwent total gastrectomy with extended right hemicolectomy to treat advanced stomach cancer with direct invasion of the transverse colon 28 months prior. He then received adjuvant chemotherapy for the next 6 months. Further chemotherapy was withheld given his unwillingness and poor general condition, combined with disease progression. Conservative management was initiated, including painkillers, megestrol to treat cachexia, and diuretics to treat edema and ascites attributable to peritoneal carcinomatosis. The patient was admitted because of persistent nausea, vomiting, and severe anorexia. His initial vital signs were nonspecific. The laboratory findings included a hemoglobin level of 11.3 g/dL, an albumin level of 2.7 g/dL, and blood urea nitrogen/creatinine levels of 23/0.6 mg/dL. Abdominal CT revealed abrupt narrowing just proximal to the small bowel in the right upper quadrant of Fig. 2A (black arrows) with diffuse upstream dilatation (white arrowheads in Fig. 2B) and a large amount of malignant ascites. We initially attempted to access the small bowel obstruction using a conventional 130-cm-long (intermediate-length) colonoscope and a 160-cm-long colonoscope (CF-H260 AL; Olympus Optical Co., Ltd., Tokyo, Japan). However, it was not possible to advance past the middle abdominal area because both scopes became twisted and we encountered severe fixation attributable to the previous surgery and diffuse peritoneal carcinomatosis (Fig. 2C). The patient underwent continuous percutaneous catheter drainage of the persistent refractory malignant ascites. We recommended surgical correction via ileostomy. However, the patient refused. We then explained that EUS-guided enteroenterostomy could be used to bridge the transenteric direct advancement of the colonoscope and perform stent insertion at the site of small bowel obstruction, bypassing the twisted small bowel. We first inserted a 7-French nasobiliary catheter (ENBD-7; Cook Endoscopy, Winston-Salem, NC, USA) (arrows in Fig. 2D) as deeply as possible into the E-loop (with instillation of contrast dye) and performed EUS-guided puncture (using a 19-gauge needle) of the target small bowel region (right lower corner of Fig. 2D). However, LAMS deployment failed because of inappropriate positioning and small bowel movement. Three days later, we performed EUS-guided enteroenterostomy using a 3 cm × 16 mm LAMS (Niti-S SPAXUS; Taewoong Medical) (white arrows, left lower corner of Fig. 2E) employing the same technique. The previously placed drainage catheter (for ascites control) was evident (arrows in Fig. 2E). We advanced transenterically through the LAMS (right lower corner) with further placement of another 8 cm × 22 mm uncovered metal stent(Niti-S, D-type; Taewoong Medical) at the small bowel obstruction site 3 days later (Fig. 2G). Follow-up CT (the next day) revealed a patent LAMS as seen in the left upper quadrant of Fig. 2G (white arrows) and that the other small bowel stent was well-positioned (arrows in Fig. 2H) in the sense that it dealt with the small bowel obstruction in the right upper quadrant; contrast passage was visible up to the distal rectum. Although the symptoms were not sufficiently improved, the patient could take in small amounts of a liquid diet. The suboptimal response to stent placement reflected the advanced, diffuse peritoneal carcinomatosis and malignant ascites. The patient died 3.5 months later of aspiration pneumonia. Schematics of the stenting performed via EUS-guided enterostomy in the two cases are shown in Fig. 3.