Kazumitsu Chou

Clinicopathologic study on pancreatic groove carcinoma.

Objectives: Pancreatic groove carcinoma usually presents with duodenal stenosis. This report describes the clinicopathologic features of 5 cases. Methods: All the clinical and radiological features were reviewed retrospectively and analyzed to identify correlations with the histological findings. Results: Vomiting was an initial symptom in all cases, but obstructive jaundice was not inevitable until the disease progresses. Hypotonic duodenography demonstrated severe postbulbar stenosis. Pathological findings of biopsy specimens showed no evidence of malignancy at the early stage. Computed tomography revealed a hypovascular mass. Magnetic resonance imaging indicated a hypointense mass on T1-weighted images and an isointense to slightly hyperintense mass on T2 images. Macroscopically, the stenosis seemed to be the result of a hard yellowish-white tumor invading the duodenal wall. Histopathologically, an adenocarcinoma arising from the groove infiltrated the submucosal layer of the duodenum circumferentially. No cancer cells were found in the mucosa at the early stage. The intrapancreatic common bile duct was involved at the advanced stage. Conclusions: We believe that these features resulted from the anatomical characteristics of the groove involvement and that the string stricture of the duodenum resulted from invasion of the groove tumor into the submucosal layer around the wall.

Multicentric pancreatic intraepithelial neoplasias (PanINs) presenting with the clinical features of chronic pancreatitis

A 46-year-old woman was readmitted to our hospital in August 2005 because of severe abdominal pain and nausea. Computed tomography demonstrated a huge cystic lesion in the retroperitoneal space behind the hepatoduodenal ligament and lesser peritoneal cavity. Endoscopic retrograde pancreatography revealed communication between the dilated main pancreatic duct and a pseudocyst. The condition was preoperatively diagnosed as chronic pancreatitis associated with a pseudocyst or an intraductal papillary mucinous neoplasm without mucin hypersecretion. The patient underwent a distal pancreatectomy with splenectomy. The pathologic diagnosis was multicentric pancreatic intraepithelial neoplasia (PanIN), and histological examination revealed a positive surgical margin around the remnant pancreas. Four months after the surgery, the patient underwent a total pancreatectomy. Macroscopic observation revealed diffuse fibrosis of the pancreatic parenchyma compatible with chronic pancreatitis. Histological examination revealed a constellation of noninvasive intraductal neoplasias with high-grade atypia, diffusely distributed in the small pancreatic ducts of the resected pancreas. Localized fibrosis and cystic dilation of the small ducts were detected in a lobule of exocrine glands draining into a ductule involved by PanIN lesions in the head of the pancreas. In summary, multicentric PanIN lesions are associated with lobular atrophy of the pancreatic parenchyma and chronic pancreatitis-like changes that follow. Total pancreatectomy may be recommended for patients with multicentric precursor lesions throughout the entire pancreas.

Improvement of Intraoperative Frozen Section Diagnosis in Patients with Biliary Strictures by Levovist Injection into the Bile Duct on Color Doppler Ultrasonography

BackgroundThis study evaluates the efficiency of color Doppler ultrasonography-guided intraoperative pancreatic biopsy (CDUS-IPB) using Levovist injected into the bile duct in conjunction with stimulated acoustic emission (SAE) in patients with biliary strictures.MethodsThe study was performed on 12 patients. After completing a conventional intraoperative pancreatic biopsy (c-IPB), each subject underwent CDUS with SAE imaging using Levovist. Upon identification of the biliary stricture, the IPB was taken from the area surrounding the stricture on the same imaging setting. Section diagnosis of the CDUS-IPB specimen was compared to that of the c-IPB specimen and resected tissue.ResultsBiliary strictures were identified as enhanced areas of color Doppler signal on CDUS. CDUS-IPB provided adequate specimens from the biliary strictures in all cases and corrected false-negative diagnoses by c-IPB in three cases. Section diagnosis by CDUS-IPB corresponded to the permanent section diagnosis. There were no complications.ConclusionsCDUS-IPB with Levovist is an accurate diagnostic tool. The method is especially useful for patients with a suspected malignant biliary stricture who show no tumor mass in preoperative images and no evidence of malignancy on cytologic examinations.