Role of external beam radiotherapy for arteriovenous malformation of the pancreas

An Update of Treatment of Pancreatic Arteriovenous Malformations

Pancreatic arteriovenous malformation is a rare entity (0.9%). There are about 200 articles available in PubMed. This review article includes 86 published articles, with 117 cases published after 2000. The median age at diagnosis was 51, and most of the patients were male (87.0%). The symptoms included pain, bleeding, pancreatitis, ulcers in the duodenum or stomach, varix formation, jaundice, and ascites. The diagnostic modalities were angiography, contrast-enhanced CT, MRI, and/or Ultra Sound. The most common treatments were surgery and embolization. The clinical success rate of embolization reported was 57.7%. The tailored embolization based on each agio-architecture had a clinical success rate of 80%. If embolic therapy is ineffective, surgical intervention should be considered.

Management of Pancreatico-duodenal arterio-venous malformation

Purpose

To describe the interventional management and clinical outcome of pancreatico-duodenal arterio-venous malformations (PDAVMs).

Material and Methods

Seven patients presenting a PDAVM (6 women, 1 male; mean age: 61) were retrospectively reviewed. Technical, clinical success and complications of embolization and surgical management of symptomatic PDAVMs were assessed. Technical success was defined as a complete occlusion of the PDAVM and clinical success as no clinical symptom or recurrence during follow-up. Patients with asymptomatic PDAVMs were followed clinically, by Doppler ultrasound and CT-angiography.

Results

Mean follow-up time was 69 months (15-180). Five symptomatic patients presented with upper gastrointestinal bleeding (n=3), ascites (n=1), and abdominal pain (n=1). Two patients were asymptomatic. The PDAVMs were classified as follow: Yakes I (1), IIIa (2), IIIb (3) and IV (1). Five symptomatic patients were treated with 9 embolization sessions with arterial approach (onyx®, glue, coils) in 7 and venous approach in 2 (plugs, coils, covered stents, STS foam and onyx®). Technical success of embolization was 60% (3/5). Devascularization was incomplete for 2 Yakes IIIB patients. Clinical success of embolization was estimated at 80% (4/5) as one patient required additional surgery (Whipple) because of persistent bleeding. One splenic vein thrombosis was treated successfully by mechanical thrombectomy and heparin. No recurrence occurred during follow-up. No progression was documented in asymptomatic patients.

Conclusion

Embolization of symptomatic PDAVMs is effective and surgery should be performed in second intention. Complete devascularization is more difficult to obtain in Yakes III PDAVM.

Transcatheter embolization of pancreatic arteriovenous malformation associated with recurrent acute pancreatitis

Pancreatic arteriovenous malformation (PAVM) is extremely rare; even rarer is its association with pancreatitis. The authors report a case of PAVM causing recurrent episodes of acute pancreatitis in a 46-year-old male. Patient refused surgery and was treated with transcatheter arterial embolization using liquid embolic agent (mixture of n-butyl-2-cyanoacrylate glue and lipiodol), which resulted in a significant decrease in the size of the PAVM.

External beam radiotherapy for angiographically diagnosed arteriovenous malformation involving the entire pancreas

Ultrasonography of a 66-year-old man with abdominal discomfort detected an abnormality of the pancreas. Multiphase contrast-enhanced computed tomography (CT) and angiography revealed arteriovenous malformation (AVM) involving the entire pancreas. The large number of dilated and tortuous feeding arteries contraindicated surgical resection or transcatheter embolization. Hemorrhage into the main pancreatic duct occurred 1 month after diagnosis. The patient underwent external radiotherapy with a total dose of 44 Gy following a conventional fractionation schedule of 2 Gy daily for 22 days administered 5 days per week. Contrast-enhanced CT after treatment confirmed disappearance of feeding vessels and nidi with no complication. Evidence of recurrence was not detected on contrast-enhanced CT 6 months after irradiation.