Pancreaticoduodenal artery pseudoaneurysm caused by segmental arterial mediolysis: a case report of surgical treatment.

A 64-year-old woman underwent surgical resection of a posterior inferior pancreaticoduodenal arterial aneurysm in the subacute phase of acute aortic dissection (AAD). Concomitantly, a distal pancreatectomy was also required. The aneurysm was approximately 20 mm in diameter. Surgical resection of the aneurysm was performed because endovascular treatment was considered to be technically difficult due to dissecting lesions that had remained at the abdominal aorta. Histopathological findings suggested this aneurysm to be a pseudoaneurysm, which had arisen as a result of segmental arterial mediolysis. Approximately 1 year after surgery, no recurrence of the aneurysms was detected.

[Arch aneurysm and ruptured innominate artery aneurysm with acute occlusion of trachea].

We reported on a case of 80-year-old woman who suffered from severe acute respiratory failure. A chest computed tomography (CT) revealed arch aneurysm and innominate artery pseudoaneurysm, which severely compressed main bronchus and trachea. After tracheal intubation in the emergency room, respiratory status improved rapidly. We immediately performed total arch replacement using deep hypothermia, circulatory arrest and the arch first technique. The postoperative course was uneventful, and stenosis of trachea resolved. Arch aneurysm associated with acute trachea occlusion is very rare and employing deep hypothermia, circulatory arrest and the arch first technique is useful for such atypical arch aneurysms.

Case of isolated thoracic aortic aneurysm as a manifestation of undiscovered giant cell arteritis.

A 73-year-old woman was referred to our hospital to investigate dilatation of an aortic arch which had been detected by a chest roentgenogram and severe aortic valve regurgitation detected by echocardiography. On admission, a computed tomography scan of the chest showed a large fusiform ascending aortic aneurysm. She had not shown any symptoms such as headache or polymyalgia rheumatica and had no significant coronary atherosclerosis. She underwent aneurysmectomy and reconstruction of the ascending aorta using cardiopulmonary bypass without aortic valve replacement, and pathological examination of the aneurismal wall revealed giant cell arteritis (GCA). Preoperatively, she did not have any temporal pain, and no signs of inflammation were detected serologically. Postoperatively, aortic valve regurgitation improved and she did well. However, three months after the surgery, she died suddenly due to the rupture or dissection of aorta. In the Japanese population, GCA is reportedly a rare cause of aortic aneurysm. However, retrospective studies show that GCA affects the aorta and that thoracic aortic aneurysm is a possible complication of GCA. In cases of the thoracic aortic aneurysms with unknown etiology, there is a possibility that GCA is the cause of the aortic aneurysm.

Mucinous cystic tumor of the pancreas: immunohistochemical assessment of "ovarian-type stroma".

The new histopathological classification of exocrine pancreatic tumors by the World Health Organization, now includes "ovarian-type stroma" ("OS") in the definition of mucinous cystic tumor of the pancreas (MCT-P). This study investigated the clinicopathological findings of the MCT-P according to WHO classification and scrutinize the function of "OS" in MCT-P immunohistochemically. Thirty-four cases of MCT-P (28 adenomas, 2 borderline tumors and 4 adenocarcinomas) were examined clinicopathologically. The "OS" of 34 MCTs-P were studied immunohistochemically and compared with the stroma of 10 mucinous cystic tumors of the ovary (MCTs-O), 10 conventional pancreatic carcinomas and 6 normal ovaries. Almost all 34 MCTs-P were located in the body-tail of the pancreas of middle-aged women. Histologically the "OS" cells exhibited luteinization in 11/34 (32.4%). Immunohistochemically, both "OS" cells and the stromal cells in MCT-O showed similar positivity rates; calponin (34/34 and 9/10), h-caldesmon (28/34 and 8/10), alpha-inhibin (29/34 and 9/10), estrogen-receptor (21/34 and 6/10) and progesterone-receptor (28/34 and 9/10, respectively). Some neoplastic epithelial cells of MCT-P were positive for human chorionic gonadotropin (hCG) (21/34, 61.8%). This study indicates the predominance of MCT in the distal pancreas of middle-aged women. Furthermore, the immunohistochemical and histological results demonstrate that the "OS" of MCT-P and the stroma of MCT-O share the same characteristics. The results also suggested that the hCG produced by the neoplastic epithelium probably plays an important role in the luteinization of the stroma of MCT-P. We therefore conclude there is a possibility that MCT-P originates from the left remnant primordial gonadal cells which migrated to the pancreatic anlage during the early development of the fetus.

Secondary extramedullary plasmacytoma involving the pancreas.

Extramedullary plasmacytoma is a rare variant of plasma cell tumor involving organs outside the bone marrow. The vast majority of extramedullary plasmacytomas present as a secondary tumor of systemic myelomatosis of the bone marrow. We experienced a patient with extramedullary plasmacytomas of the head and tail of the pancreas presenting as secondary masses from extramedullary plasmacytoma of the maxillary sinus that had been treated 5 years previously. A 38-year-old Japanese man had undergone radiation therapy for an extramedullary plasmacytoma of the maxillary sinus 5 years before the current presentation. He experienced severe upper abdominal pain in November 1999, when laboratory data showed elevation of the serum amylase level. Computed tomography showed two isodensity masses, in the head and tail of the pancreas. Angiography showed two hypervascular masses, one in the head and the other in the tail of the pancreas, and encasement of the portal vein trunk junction. Laparotomy was performed, with the tentative diagnosis of extramedullary plasmacytoma of the pancreas, in order to obtain a definite diagnosis. Intraoperative biopsy revealed that the two pancreatic masses were extramedullary plasmacytomas. External radiation therapy was performed after the operation. When a pancreatic mass is noticed in patients with a history of plasmacytoma, secondary extramedullary plasmacytoma of the pancreas should be considered as a differential diagnosis.