Pancreaticoduodenal artery aneurysm associated with coeliac artery occlusion from an aortic intramural hematoma

Pancreaticoduodenal artery aneurysms are a rare type of visceral artery aneurysm, whose rupture is associated with high mortality. These aneurysms are of particular interest because local haemodynamic change caused by coeliac artery obstruction plays an important role in their development. However, the pathophysiological mechanism of coeliac artery obstruction is not completely understood. Pressure from the median arcuate ligament is most frequently reported cause. Although it is well-known that stenosis or occlusion of the visceral vessels may be caused by aortic syndrome, reports of pancreaticoduodenal artery aneurysm associated with coeliac artery occlusion due to aortic syndrome are extremely rare. Our case indicates a new aetiology for a pancreaticoduodenal artery aneurysm and demonstrates the rapid deterioration of the patient affected.

Protracted anaphylaxis developed after peginterferon α-2a administration for chronic hepatitis C

Peginterferon is a key drug used to treat chronic viral hepatitis that is known for causing various side effects.Side effects occurring immediately after administration include headache, nausea, and influenza-like symptoms, such as fever and joint pain.However, reports of anaphylactic shock are extremely rare.Here we report a patient with protracted anaphylaxis who suffered shock symptoms after peginterferon α-2a administration for chronic hepatitis C.Although the patient improved temporarily with shock treatment, symptoms of anaphylaxis recurred.As peginterferon is often administered on an outpatient basis, it is important to recognize life-threatening side effects that may develop in a protracted manner.

Greater omentum gastrointestinal stromal tumor with PDGFRA-mutation and hemoperitoneum

Although gastrointestinal stromal tumor(GIST) occurs generally in the digestive tract,omental GIST is very rare.We report the first case of an adult greater omental GIST with a new platelet-derived growth factor receptor α gene(PDGFRA)-mutation with hemoperitoneum.A 43-year-old man was admitted to our hospital complaining of acute abdominal pain.Abdominal contrast-enhanced computed tomography revealed a huge mass in the right abdominal cavity,and a large accumulation of fluid in the pelvic cavity,suggesting hemoperitoneum.We diagnosed the rupture as an intra-abdominal tumor,and an emergency tumorectomy was performed with resection of the greater omentum.This tumor was located in the distal right side ofthe greater omentum,and showed no continuity with the gastric wall.The tumor occurred primarily in the greater omentum.The resected tumor was about 19 cm × 12 cm × 14 cm in diameter,and weighed 1529 g.Histologically,the tumor was composed of epithelioidshaped cells with high cellularity,and was positive for CD117 and CD34,and negative for S-100,α-smooth muscle actin.The mitosis was 6/50 under high power field.This case showed exon 18 mutation of PDGFRA with 846(Asp to Glu) substitution,848(Asn to Lys) substitution.This is the first report of this PDGFRA mutation in omental GIST,and this might play an important role in the tumorigenesis of this case.Based on these findings,the tumor was diagnosed as high risk GIST primarily occurring in the greater omentum.The patient was treated with imatinib at a dose of 400 mg/d as adjuvant chemotherapy,and has been followed up for 24 mo with no evidence of recurrence.