Soo Tae Kim

Intraductal variant of peripheral cholangiocarcinoma of the liver with Clonorchis sinensis infection

Peripheral cholangiocarcinoma arises from the small bile ducts and presents with an infiltrative growth, but intraductal growth in the peripheral large duct tributaries is an extremely unusual manifestation, especially in cases with Clonorchis sinensis infection. A case of surgically resected intraductal variant of peripheral cholangiocarcinoma of the liver in a 46‐year‐old Korean man who had eaten raw fresh‐water fish is described. The tumors were entirely confined within the dilated peripheral tributaries of the left intrahepatic bile duct, and no tumorous extention beyond the bile duct walls into the hepatic parenchyma or to the hilum was found. Microscopically, the tumor was a well‐differentiated papillary adenocarrinoma of large duct origin, and the major branches were plugged with multiple tumor casts. A histologic feature of a C. sinensis infection with fully developed adenomatous hyperplasia was associated in the peripheral septal ducts, and the nonneoplastic large duct showed focal epithelial dysplasia. The authors assume that intraductal cholangiocarcinoma is a distinct macroscopic subtype, and that a C. sinensis infection may also be responsible for its development.

Papillary cystic tumor of the liver. A case report with ultrastructural observation

A case of primary tumor of the liver with pathologic features strikingly similar to those of the papillary cystic tumor of the pancreas in a 41‐year‐old woman is presented. Two large, well‐demarcated, solid and cystic tumors with extensive hemorrhage and necrosis were located in the right and left lobes, measuring 30 × 27 × 7.5 cm and 5.5 × 4.0 × 2.5 cm, respectively. Microscopically, both tumor masses showed two basic patterns of cellular arrangement. One was a papillary pattern with fairly prominent fibrovascular stalks covered with one to three cell layers of tall to cuboidal cells. The other pattern was that of solid growth with microcystic degeneration. Ultrastructurally, the tumor cells were polyhedral and their oval shaped nuclei were occasionally indented. The cytoplasmic organelles varied in amount, and immature cell junctions and intercellular spaces were rarely present. A few cells contained zymogen‐like secretory granules and annulate lamellae. The pancreas was free of tumor. To our knowledge, this tumor is a unique clinicopathologic entity of hepatic origin, and its similarity to the pancreatic papillary cystic tumor in clinical, gross, microscopic, and ultrastructural features together with their closely related organogenesis, suggests that this tumor derives from pluripotential cells transdifferentiating toward the pancreatic acinar cells and ductular cells, with the latter being indistinguishable from intrahepatic small bile ductular epithelial cells.

Postoperative recurrence of hepatocellular carcinoma: Results of transcatheter arterial chemoembolization

A retrospective analysis was made of the effect of transcatheter arterial chemoembolization (TACE) in 87 patients with recurrent hepatocellular carcinoma (HCC). In contrast to the predominantly single nodular HCC (60.2%) on preoperative angiography, recurrent HCC showed a multinodular pattern in 54.2%. Preoperative TACE had significantly prolonged the interval between surgery and recurrence. One- and 2-year survival rates after TACE of the 87 recurrent HCCs were 74.7% and 55.%, respectively, which were not significantlydifferent from those of a control group of 206 patients with HCC in Childs class A, who were treated with TACE only. We believe that TACE is an effective measure in the management of preoperative and recurrent HCC.

Sonographic characteristics of small hepatocellular carcinoma

Fifty-four lesions of small hepatocellular carcinoma under 5 cm in diameter detected by real-time sonography were reviewed to characterize the sonographic feature. Twenty-nine lesions were smaller than 3 cm in diameter and 25 were between 3 and 5 cm in diameter. Sonographic characteristics of hepatocellular carcinoma were peripheral hypoechoic halo (52%), lateral shadow (26%), posterior acoustic enhancement (44%), and mosaic pattern (24%) of the mass. Small tumors less than 3 cm in diameter showed a hypoechoic pattern in half of the cases, whereas most of the tumors between 3 and 5 cm in diameter showed a hyperechoic or mixed pattern. Posterior acoustic enhancement was commonly seen in small tumors less than 3 cm in diameter, while a mosaic pattern was commonly seen in large tumors between 3 and 5 cm in diameter. These results suggest that sonography might be useful for the characterization of small hepatocellular carcinoma.

Mosaic Pattern of Encapsulated Hepatocellular Carcinoma: Correlation of Magnetic Resonance Imaging and Pathology

Internal architecture of an encapsulated hepatocellular carcinoma (HCC) was studied with magnetic resonance imaging and histologic correlation. The capsule of HCC showed low intensity relative to liver on both T1- and T2-weighted images. The T1-weighted images were superior to the T2-weighted images in delineating the capsule of HCC. The tumor showed a mosaic pattern, which was a configuration composed of multiple compartments of different intensities, reflecting viable tumor nodules and a necrotic portion. Viable tumor nodules, composed of trabeculae of polygonal cells resembling the normal liver cell with well-formed sinusoids, showed low intensity relative to liver on T1-weighted images and high intensity on T2-weighted images. The necrotic portion, composed of coagulation of amorphous, thick eosinophilic material without hemorrhage or inflammatory reaction, showed low intensity relative to liver on both T1- and T2-weighted images. The T2-weighted images were superior to the T1-weighted images in demonstrating the mosaic pattern of HCC.

Intraoperative sonography of hepatocellular carcinoma: Detection of lesions and validity in surgical resection

Eighty-six hepatocellular carcinomas (HCCs) in 67 patients were examined by intraoperative sonography. Sensitivity for detecting tumors with intraoperative sonography was compared with sonography, computed tomography (CT), hepatic angiography, and CT after intraarterial injection of iodized poppy-seed oil (Lipiodol-CT). The overall sensitivities were 76% with sonography, 86% with CT, 89% with angiography, 96% with Lipiodol-CT, and 98% with intraoperative sonography. The differences in sensitivity between intraoperative sonography and sonography (p < 0.01), CT (p < 0.01), and angiography (p < 0.05) were significant. In 35 lesions smaller than 2 cm, the sensitivities of Lipiodol-CT and intraoperative sonography were high (91 and 94%, respectively). In operating field, tumors were invisible in 36 (42%) and nonpalpable in 31 of 86 cases (36%). In 35 tumors smaller than 2 cm, invisible tumors were 66% and nonpalpable tumors were 63%. However, 84 of 86 cases (98%) could be localized with intraoperative sonography.These results suggest that intraoperative sonography is the final diagnostic imaging procedure before surgical resection of tumors and in cases of invisible and nonpalpable tumors in the operating field, this procedure is mandatory to improve surgical results.