Pancreatic pseudoaneurysm can result from pancreatitis, trauma, infection, and iatrogenic causes such as vascular interventions, and abdominal surgeries. It is reported that one-quarter of patients with pancreatitis may develop vascular complications.^1,2 Splenic artery is the most commonly involved artery, followed by the left gastric gastroduodenal, and pancreaticoduodenal arteries.^3,4 Pseudoaneurysm rupture is a serious condition that sometimes leads to death.⁵ It is often treated with transcatheter arterial embolization (TAE), after which the re-rupture rate is 6%.⁶ Herein, we report a case of ruptured pseudoaneurysm that was successfully prevented re-rupture with pancreatic pseudocyst drainage by using lumen-apposing metal stent (LAMS) following TAE.

A 59-year-old man presented with back pain. Contrast-enhanced computed tomography (CECT) revealed pancreatic tail cancer with multiple liver metastases (Fig. 1A). After the administration of three courses of gemcitabine combined with nab-paclitaxel, CECT revealed complete response with shrinkage of the pancreatic cancer and disappearance of liver metastases. However, the patient experienced abdominal pain with elevated serum levels of pancreatic amylase and C-reactive protein (CRP). He had not consumed alcohol recently. CECT revealed pancreatic pseudocyst with a patchy high-density area between the stomach and pancreas (Fig. 1B), suggesting pseudoaneurysm rupture into the pseudocyst. The patient underwent angiography, wherein the splenic artery pseudoaneurysm was embolized using TAE with embolic material (Fig. 1C). Subsequently, pseudocyst drainage was performed using LAMS (Hot AXIOS; Boston Scientific) to prevent pseudoaneurysm re-rupture (Fig. 2A–2D). The LAMS with an inner diameter of 20 mm and 7 Fr double pig tail plastic stent were placed in the pancreatic pseudocyst and a large amount of blood and pancreatic juice was discharged. Thereafter, the pseudocyst shrieked with decreased serum levels of CRP, allowing the patient to re-institute chemotherapy (Fig. 2E). This LAMS dislocated spontaneously without recurrence of pseudoaneurysm. The patient continued chemotherapy and died 16 months after LAMS placement.

Figure 1. (A) Contrast-enhanced computed tomography (CECT) revealed pancreatic tail tumor and multiple liver tumors. (B) CECT after three courses of chemotherapy revealed pancreatic pseudocyst with a patchy high-density area between the stomach and pancreas (arrows). (C) Angiography revealed a pseudoaneurysm of the splenic artery (arrow head).

Figure 2. (A) Endoscopic ultrasound (EUS) revealed pancreatic pseudocyst with high and low echoic area. (B–D) EUS guided pseudocyst drainage was performed by using lumen-apposing metal stent. (E) Contrast-enhanced computed tomography revealed shrieked pseudocyst.

The case report was approved by th ethical committee of Kansai Medical University (No. 2015642). The informed consent was waived.

This is the first report of pancreatic pseudocyst drainage by using LAMS after TAE for ruptured pseudoaneurysm. It is reported that success rate of TAE for pseudoaneurysm was 70%–90%.⁷ Although the benefits of endovascular therapy have been proven over the years with increasing success rates, complications such as recurrence, stent infection, displacement, migration, and splenic infarction may occur. Therefore, treatment must be tailored to the individual patient, and embolization may only be used as a bridging treatment for some patients.³ In this case, a pancreatic pseudocyst was found in a patient with no history of alcohol consumption. The chemotherapy for pancreatic cancer was remarkably effective, which may have caused the tumor lysis, resulting in the formation of a pseudocyst and pseudoaneurysm. Ueno et al⁸ reported that late onset of acute pancreatitis after chemotherapy with gemcitabine plus nab-paclitaxel for metastatic pancreatic cancer and the remarkable effectiveness of chemotherapy led to the rapid shrinkage of the pancreatic tumor, which may have caused the acute pancreatitis. Pancreatic juice within the pancreatic pseudocyst stimulated the pseudoaneurysm, causing it to rupture. In addition, in this case, a pseudoaneurysm had been confirmed to have ruptured within the pancreatic cyst, and the cyst was filled with blood clots. The reason for decision to use the LAMS was that it was predicted that blood occlusion would occur early if only a plastic stent was placed. Therefore, pancreatic pseudocyst drainage using LAMS was performed to prevent pseudoaneurysm re-rupture following TAE. Furukawa et al⁹ reported splenic artery rupture occurring during chemotherapy for pancreatic cancer, which required conversion surgery following TAE. Rana et al¹⁰ reported on the safety and efficacy of pancreatic fluid drainage after angioembolization of pseudoaneurysm. We also placed a double pigtail plastic stent within a LAMS. There are some reports that additional placement of a double pigtail plastic stent within the LAMS reduced complications that it does not.^11–14 In this case, because the pseudoaneurysm had already ruptured, we placed a double pigtail plastic stent within the LAMS because we thought that mechanical stimulation of the LAMS was likely to cause the aneurysm to re-rupture. Thus, splenic artery pseudoaneurysms should be carefully monitored during chemotherapy for pancreatic cancer. In addition, pseudocyst drainage was effective when the pancreatic pseudoaneurysm had a high risk of rebleeding due to exposure to pancreatic juice.

None.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

No potential conflict of interest relevant to this article was reported.