佐田 尚宏

CONTEXT: Although rare, a pancreatic arteriovenous malformation can have serious consequences. A diagnosis of arteriovenous malformation requires evidence of aberrant communication between the arterial and the venous systems. This report describes a case where the use of multi-detector row CT and specific post-processing methods provided a diagnosis of arteriovenous malformation. This minimally invasive diagnostic approach resulted in a clear, precise and comprehensive visual representation of the pancreatic arteriovenous malformation. CASE REPORT: A 60-year-old man with right hypochondriac pain presented with a mass in the head of the pancreas. The hypochondriac pain resolved spontaneously and physical examination revealed no abnormal findings. A multi-detector row CT study was performed. The data obtained in the arterial phase demonstrated a high-contrast mass in the head of the pancreas and early enhancement of the portal vein. A maximum intensity projection method clarified the aberrant vascular communication. Changes in Hounsfield numbers were observed using a multi-planar reformation method. A volume-rendering method was used to create a 3D model which demonstrated the spatial relationship between the aberrant vascular communication and the surrounding tissue. An annual follow-up study using this technique showed no significant alteration. CONCLUSIONS: Multi-detector row CT with specific post-processing methods is a useful diagnostic tool for pancreatic arteriovenous malformation.

A 60-year-old man presented with melena and hematemesis in 1984. Esophagogastroduodenoscopy (EGD) detected a small protruding lesion in the duodenal bulb, which was diagnosed as Brunner's adenoma. No significant change was detected in subsequent annual EGD and biopsies for 10 years, after which the patient was not observed for 7 years. The patient presented with melena again in 2001. The lesion had changed shape to become a 10 mm sessile tumor with a central depression, and following a biopsy was diagnosed as an adenocarcinoma. The patient underwent partial resection of the duodenum. Histopathological assessment showed acidophilic cells with swollen nuclei, and clear cells forming a tubular or papillary tubule in the mucosal lamina propria and submucosal layer. The tumor cells stained positive for lysozyme, indicating that they arose from Brunner's gland. The patient showed no sign of recurrence and was disease-free for more than 34 months after surgery. The patient died of pneumonia. This is an extremely rare case of primary duodenal carcinoma arising from Brunner's gland in a patient observed for 17 years.