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Gastroenterology | 1986

Natural History of Minute Hepatocellular Carcinoma Smaller Than Three Centimeters Complicating Cirrhosis

Masaaki Ebara; Masao Ohto; Takashi Shinagawa; Nobuyuki Sugiura; Kunio Kimura; Shoichi Matsutani; Masahiko Morita; Hiromitsu Saisho; Yukihiro Tsuchiya; Kunio Okuda

Twenty-two patients with cirrhosis and minute hepatocellular carcinoma less than 3 cm in diameter were followed for periods of 6-37 mo without specific treatment. The survival curve drawn by the Kaplan-Meier method showed a 1-yr survival of 90.7%, a 2-yr survival of 55.0%, and a 3-yr survival of 12.8%. The ultrasonic patterns of these masses in the liver were correlated with the size and showed a tendency to change from a low echo pattern to a low periphery and, finally, to a massive pattern. The growth speed calculated from the doubling time for tumor volume varied considerably from case to case with an average of 6.5 +/- 5.7 mo; it also changed in some cases during the observation period. Serum alpha-fetoprotein levels were generally low, rarely assisted in diagnosis, but tended to increase when the mass attained a diameter of greater than 3 cm; sudden acceleration in the rate of increase in alpha-fetoprotein level often coincided with a change of ultrasonic pattern to the massive one.


Gastroenterology | 1984

Diagnosis and Clinical Features of Small Hepatocellular Carcinoma With Emphasis on the Utility of Real-Time Ultrasonography: A Study in 51 Patients

Takashi Shinagawa; Masao Onto; Kunio Kimura; Shigeyuki Tsunetomi; Masahiko Morita; Hiromitsu Saisho; Yukihiro Tsuchiya; Naoki Saotome; Eii Karasawa; Makoto Miki; Takatsugu Ueno; Kunio Okuda

The clinical features and usefulness of various methods for diagnosis of small hepatocellular carcinoma, no greater than 5 cm in diameter, were studied in 51 patients. The diagnosis was verified in 28 patients by hepatic resection and in 4 patients at autopsy. The tumor was less than 3 cm in diameter in 23 patients. In 37 patients (72.5%), the tumor was first discovered by real-time linear scan ultrasonography, generally during a routine periodic follow-up examination of patients with chronic liver disease, mostly cirrhosis. Clinically, 62.7% of the patients were asymptomatic, and symptoms in the remainder were not suggestive of carcinoma. Most patients showed only mildly abnormal liver function tests that did not suggest the diagnosis. Serum alpha-fetoprotein level was normal in 25.5%, and it was elevated above 200 ng/ml in only 33.3%. Among the various imaging modalities, ultrasonography had the highest detection rate (92.2%) for these small hepatocellular carcinomas compared with computed tomography (73.2%), scintigraphy (50.0%), and angiography (86.0%). False-positive lesions, however, were also found frequently by ultrasonography, requiring ultrasonography-guided biopsy for differential diagnosis in some of the patients. Routine examination at regular intervals of patients with chronic liver disease using a combination of real-time ultrasonography and alpha-fetoprotein measurement is currently the most effective approach to detecting small hepatocellular carcinoma.


Gastroenterology | 1985

Association of gallbladder carcinoma and anomalous pancreaticobiliary ductal union

Kunio Kimura; Masao Ohto; Hiromitsu Saisho; Takao Unozawa; Yukihiro Tsuchiya; Masahiko Morita; Masaaki Ebara; Shoichi Matsutani; Kunio Okuda

A total of 96 patients with gallbladder carcinoma in whom direct cholangiography clearly opacified the pancreaticobiliary ductal union and the common channel, and 65 patients with an anomalous union of these two duct systems at a distance greater than 15 mm from the papilla of Vater (normally less than 4.6 +/- 2.2 mm, mean +/- SD) were studied. It was found that this anomalous ductal union occurred in 16.7% of the patients with gallbladder carcinoma in comparison with an incidence of 2.8% among 641 consecutive patients with various hepatobiliary and pancreatic diseases studied by endoscopic retrograde cholangiopancreatography who did not have gallbladder carcinoma. It was also found that gallbladder carcinoma occurred in 24.6% of the 65 cases of anomalous ductal union in comparison with a 1.9% incidence of this cancer among 635 consecutive patients similarly studied and found to have normal ductal union (p less than 0.001). Thus, a close etiologic association was suggested between this anomaly in the terminal segment of the biliary tract and gallbladder carcinoma. Of the 65 patients with anomalous ductal union, 50 had the so-called congenital cystic dilatation of the common bile duct and 15 did not. Five of the 50 (10%) and 11 of the 15 (73.3%) had gallbladder carcinoma (p less than 0.01), and this carcinoma seems to be related to anomalous ductal union rather than to cystic dilatation of the common bile duct. As a tumorigenic factor in this anomaly, regurgitation of pancreatic juice has been stressed.


Digestive Diseases and Sciences | 1984

Bacteriological study of transhepatically aspirated bile: Relation to cholangiographic findings in 295 patients

Yasutoshi Suzuki; Akio Kobayashi; Masao Ohto; Yukihiro Tsuchiya; Hiromitsu Saisho; Kunio Kimura; Takanori Ono; Kunio Okuda

The purpose of this study was to elucidate the frequency of bacterial infection of intrahepatic bile in relation to biliary tract pathology. Bile was aspirated during percutaneous transhepatic cholangiography, with or without combined biliary tract drainage, and subjected to bacteriological investigations in 295 patients with various hepatobiliary diseases. Bile was infected in 89% of the 92 patients who had high fever and were on antibiotics at the time of study. Positive cultures were obtained in 39% of the patients who were not so ill as to require antibiotics. The overall incidence of biliary infection was 90% in bile duct stones, particularly high in patients with primary intrahepatic stones, regardless of the presence of stones in the common bile duct, and in patients who had dilation of the common bile duct, presumably due to obstructive involvement of the ampulla of Vater.E. coli andKlebsiella were the most frequent among the aerobic species isolated, and mixed infection involving these organisms was common. Anaerobes were much less frequent, always mixed with aerobes, but positive cultures would increase with more rigorous anaerobic conditions for culture. Duodenal fluid collected simultaneously did not always grow the same microorganisms, but showed a 86–87% coincidence with intrahepatic bile in terms of positive or negative cultures. It is recommended that bile be cultured at the time of percutaneous transhepatic cholangiography.


British Journal of Radiology | 1988

Pulsed Doppler in the diagnosis of small liver tumours

Kazuaki Yasuhara; Kunio Kimura; Masao Ohto; Shoichi Matsutani; Masaaki Ebara; Yukihiro Tsuchiya; Hiromitsu Saisho

Doppler ultrasound detection of the blood flow associated with liver tumours was studied in primary hepatocellular carcinoma as well as in metastatic liver cancer and haemangioma. Doppler signals were detected from 48 of 55 hepatocellular carcinomas (87.3%), seven of 25 metastatic liver cancers (28.0%) and four of 30 haemangiomas (13.3%). The waveforms of Doppler signals were divided into two types: the pulsatile wave, which was detected from hepatocellular carcinoma (in 35 of the 48 with Doppler signals) and metastatic liver cancer (in all seven with positive signals), and the continuous wave, which was seen from hepatocellular carcinoma (41 out of 48) and haemangioma (in all four with signals). In six patients with hepatocellular carcinoma who underwent transcatheter arterial embolization, the pulsatile wave detected before therapy disappeared immediately thereafter and it is possible that this type of wave originates from tumour vessels. In the study of small, hypoechoic, mass lesions appearing in liver cirrhosis, such signals were also demonstrated, even in eight of 10 small hepatocellular carcinomas less than 2 cm in diameter, whilst they were not detected from nine regenerative nodules related to cirrhotic change. In conclusion, the Doppler ultrasound method may be a useful technique in detecting blood flow within liver tumours and may offer the possibility of a differential diagnosis of small tumours.


European Journal of Radiology | 2002

Diagnosis of gallstone composition in magnetic resonance imaging: in vitro analysis

Minoru Ukaji; Masaaki Ebara; Yukihiro Tsuchiya; Hirotoshi Kato; Hiroyuki Fukuda; Nobuyuki Sugiura; Hiromitsu Saisho

OBJECTIVE To elucidate the cause of the signal intensity of gallstones on magnetic resonance (MR) images and to determine whether MR imaging would enable the prediction of the composition of gallstones. MATERIALS AND METHODS 50 gallstones removed by cholecystectomy from 50 patients were used for in vitro study. All 50 gallstones were examined by MR imaging using a body phantom. After imaging, all gallstones were cut into two pieces, and the MR appearances were compared with their cross-sections. Chemical analysis was subsequently performed on 32 gallstones. RESULTS On T2-weighted (T2W) images, 24 of 50 gallstones showed high signal intensities only in their center. These central high intensities seen on T2W images corresponded to the clefts filled with fluid within gallstones. In 45 of 50 gallstones there were high signal intensity areas in central and/or peripheral regions on T1-weighted (T1W) images. On T1W images, not only the clefts within gallstones but also other regions were seen as high intensity, and these regions had a brown to black color, coarse structure, and contained much copper. CONCLUSION MR imaging can visualize the structures and compositions of gallstones in detail.


Radiology | 1976

Hepatic Lymphatics as Opacified by Percutaneous Intrahepatic Injection of Contrast Medium: Analysis of Hepatic Lymphograms in 125 Cases

Kunio Okuda; Toshlo Sumikoshi; Yoshiro Kanda; Yoshio Fukuyama; Hirofumi Koen; Hirotaka Musha; Koji Suzuki; Yukio Nakashima; Yukihiro Tsuchiya; Kazuro Kotoda

Hepatic lymph vessels were opacified in 125 patients with various hepatobiliary diseases during percutaneous transhepatic cholangiography or portography. Contrast medium deposited in the parenchyma flowed relatively quickly in winding channels, usually toward the hepatic hilus. No correlation was demonstrated between the locus of the intraparenchymal deposit and the direction of the flow. Contrast medium also opacified the lymphatics near the hepatic hilus and abdominal aorta. Neither jaundice nor liver disorder were prerequisite for the visualization of the hepatic lymphatics. The intrahepatic injection of contrast medium provides a safe and useful method for the study of hepatic lymph and its pathways.


Journal of Gastroenterology and Hepatology | 2001

Long-term evaluation of extracorporeal shock-wave lithotripsy for cholesterol gallstones.

Reiko Tsumita; Nobuyuki Sugiura; Masaaki Ebara; Hiromitsu Saisho; Yukihiro Tsuchiya

Background: Extracorporeal shock‐wave lithotripsy (ESWL) is a treatment that preserves the gallbladder. Problems after ESWL treatment include stone recurrence and the development of biliary symptoms.


Journal of Gastroenterology | 1995

Repeated piezoelectric lithotripsy for gallstones with and without ursodeoxycholic acid dissolution: A multicenter study

Yukihiro Tsuchiya; Fumitake Ishihara; Goro Kajiyama; Saburo Nakazawa; Masao Otho; Hiroshi Tanimura; Yoshikazu Akura; Minoru Harada; Masabumi Hihara; Yukio Kawai; Yukihiro Kono; Hajime Koshiyama; Masahiro Morita; Michiko Nakajima; Kyoichiro Nishina; Sagawa H; Terufumi Sakai; Mitsuo Shoji; Kayoko Sone; Yoshihiro Sugimoto; Keiichi Sugiyama; Osamu Takahara; Tomoo Takamura; Susumu Tazuma; Hideki Wakamatsu

The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.


Journal of Gastroenterology and Hepatology | 1989

Diagnosis of small hepatocellular carcinoma by computed tomography: Correlation of CT findings and histopathology

Shigeyuki Tsunetomi; Masao Ohto; Yasuo Iino; Takashi Shinagawa; Kunio Kimura; Masahiro Morita; Hiromitsu Saisho; Yukihiro Tsuchiya; Noboru Hirooka; Kunio Okuda

The diagnostic value of computed tomography (CT) scans in small hepatocellular carcinoma (HCC) (<5 cm) was studied in 82 patients. Dynamic scan was also made in 66 of them. Combined unenhanced and enhanced scans detected 87% of the lesions > 2 cm, but the detection rate was only 25% for lesions <1.5 cm. Diagnostic failure was due to isodensity of the mass and to technical artefacts. Diagnosis of the surrounding capsule and internal septa (partition) and demonstration of the typical pattern of density enhancement by dynamic scan proved useful in differentiating HCC from secondary cancers. On unenhanced CT, the density of the interior was subject to the histological changes of tumour such as bleeding, necrosis and fatty metamorphosis. Similarly, enhanced CT showed density changes suggestive of these histological changes. Dynamic scan proved particularly useful for lesions <3 cm because the typical density enhancement was frequently demonstrated in the arterial phase. It was concluded that unenhanced CT combined with dynamic scan has a high diagnostic value in small HCC and reflects histological changes.

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