Large acinar cell carcinoma of the pancreas in a patient with elevated serum AFP level.

A pancreatic carcinoma, associated with elevated serum alpha-fetoprotein level, was resected from a 67-year-old man. The tumor was strongly suggested to be an acinar cell carcinoma of the pancreas, based on the histological findings of the resected specimen. The tumor measured 12 x 10 x 9 cm, and the cut surface was soft, whitish-yellow, focally necrotic, and hemorrhagic. Under a light microscope, the tumor cells were not arranged in a tubular and trabecular pattern, but rather, showed a tendency toward an acinar structure. Immunohistochemically, alpha 1-antitrypsin- and alpha 1-antichymotrypsin-positive reactions were diffusely positive in most of the tumor cells, while staining for chromogranin, neuron-specific enolase, Grimelius, glucagon, insulin, and alpha-fetoprotein was negative in the tumor cells. We report a large acinar cell carcinoma (associated with elevated serum alpha-fetoprotein level), which had been misdiagnosed as hepatocellular carcinoma preoperatively.

Pathomorphologic study on the mechanism of fatty change in small hepatocellular carcinoma of humans.

BACKGROUND/AIMS: Fatty change is frequently observed in small hepatocellular carcinoma (HCC) of the early stage. However, the mechanism of fatty change and its pathomorphological features in small HCC are not yet fully understood. These issues are addressed here. METHODS: Histological examinations were conducted on 260 HCC nodules (< or =3 cm in diameter) which were surgically obtained from 249 patients. According to the distribution pattern, fatty changes were classified into two types: 'diffuse type' when the change was found throughout the cancerous nodule; and 'focal type' when the change was localized in part of the nodule. To study the pathogenesis of fatty change in HCC in relation to angioarchitecture, the number of arterial tumor vessels and intratumoral portal tracts in 104 of the 260 nodules was counted. RESULTS: Fatty change was found in 51 of the 260 nodules (19.6%), the frequency was highest (36.4%) in the nodules whose diameter was 1.1 to approximately 1.5 cm, and the frequency decreased with the increase in tumor diameter. Small well-differentiated HCCs were often associated with a diffuse type fatty change. With the increase in tumor diameter, moderately differentiated cancerous tissues without associated fatty change appeared, and the focal type was found more frequently. According to the angioarchitecture, in HCCs < or =1.5 cm, the number of intratumoral arteries was significantly smaller in HCCs with fatty change (p<0.05), though the number of intratumoral portal tracts was not significantly different compared with HCCs without fatty change. CONCLUSION: These findings suggest that fatty change of small HCC is closely related to the tumor size, the histological grade and insufficient development of the arterial tumor vessels.

A so-called carcinosarcoma of the gallbladder in a patient with multiple anomalies--a case report.

The patient was a 65-year-old woman with a chief complaint of right upper quadrant pain. Under the diagnosis of gallbladder tumor, preduodenal portal vein and absence of the pancreatic tail, cholecystectomy was performed. Intraoperative findings resulted in a diagnosis of gallbladder tumor, absence of the pancreatic tail, presence of preduodenal portal vein, and malrotation of the intestine. Histological examination of the resected specimens showed a so-called carcinosarcoma. Carcinosarcoma of the gallbladder is a rare tumor of the hepatobiliary region. The present case differs from previously reported cases in its presentation with multiple anomalies including the presence of preduodenal portal vein. Many cases of preduodenal portal vein in an association with duodenal stenosis in children have been reported, but reports of cases of preduodenal portal vein in adult patients are rarely seen in the literature.

Clinicopathological study on hepatocellular carcinoma with lymphocytic infiltration.

We examined the clinicopathologic features of 11 surgically resected hepatocellular carcinomas (HCCs) less than 3 cm in diameter with marked inflammatory cell infiltration (LHCCs). In comparison with the other 152 HCCs without such an infiltration (controls), there were no significant differences in male/female ratio, age, serum alpha-fetoprotein levels, and laboratory and imaging findings. All the 11 LHCC cases were hepatitis B surface antigen (HBsAg) negative and hepatitis C virus antibody positive. Among the 152 controls, 116 cases were also HBsAg negative and HCVAb positive and were referred to as HCV-only controls. The clinical features were not significantly different between the LHCC and the HCV-only controls. The LHCC group tended to have higher numbers of lymphocytes and monocytes in pre- and post-operative peripheral blood, but there were no significant group differences. Recurrence rate was 9.1% in the LHCC group, 47.7% in the controls and 47.5% in the HCV-only controls (P < .01). Five-year survival rate was 100% in the LHCC group, 65.1% in the controls and 68.1% in the HCV-only controls (P < .01). Histologically, remarkable inflammatory cell infiltration, mostly lymphocytic, was observed in the cancerous tissue of the LHCC group. Varying degrees of piecemeal necrosis of cancer nests produced by infiltrating lymphocytes were observed in all the 11 cases. Lymph follicle formation was also found in 10 of 11 cases (90.9%). Liver cirrhosis was associated in 6 LHCC cases (54.5%), in 117 control cases (77.0%), and in 91 HCV-only controls (78.4%). Tumor invasion into the portal vein in the vicinity of the tumor was found in 1 LHCC case (9.1%), in 54 controls (35.5%), and in 34 HCV-only controls (29.3%). Immunohistochemically, most of the infiltrating lymphocytes, other than those in the lymph follicle, were identified as T lymphocyte, and CD8+ T lymphocyte was more predominant than CD4+ T lymphocyte. Better prognosis of the LHCC group could attribute to the anti-tumor effect induced by cellular immunity of CD8+ and CD4+ T lymphocytes, and partly by humoral immunity of B cells which formed lymph follicles.

Serous cystadenocarcinoma of the pancreas with liver metastases.

Serous cystadenocarcinoma of the pancreas is a rare entity. We report a primary tumor of the pancreas in a 56-year-old woman that was histologically indistinguishable from microcystic adenoma, but which behaved in a malignant fashion. Metastatic lesions were found in the liver at the time of the initial operation. Nine years after the initial operation, new metastatic liver nodules were found, and the histologic characteristics of these lesions were quite similar to those of the pancreatic neoplasm. This is a very rare case which may support the existence of the entity, serous cystadenocarcinoma of the pancreas.

Hepatocellular carcinoma with sarcomatous change.

We studied clinicopathological and immunohistochemical features of hepatocellular carcinoma (HCC) with sarcomatous change among surgically resected HCC cases. Among 308 HCC cases, 6 (1.9%) showed partial (5 cases) or entire (1 case) sarcomatous change. Only 1 case received preoperative anti-cancer therapy among the 6 cases, suggesting that sarcomatous change is not always related to anti-cancer therapy. Immunohistochemically, the sarcomatous components were positive for albumin and alpha 1-antichymotrypsin and negative for alpha-fetoprotein in all cases. Expressions of intermediate filament-related proteins (e.g., cytokeratin and vimentin) in the sarcomatous components were heterogeneous. The sarcomatous components showed stronger expressions of p53 protein and/or mouse double minute-2 protein, and higher proliferating cell nuclear antigen labeling index, suggesting their high proliferative activity and high malignant potential.