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F Wakao

Publications and source records attributed to F Wakao.

31 records · Page 2Linked to original sources
PubMed1993

Response of early-stage hepatocellular carcinoma and borderline lesions to therapeutic arterial embolization.

OBJECTIVE: In Japan, borderline lesions and early-stage hepatocellular carcinoma (HCC) are now histopathologically divided into two subgroups; one includes adenomatous hyperplasia and atypical adenomatous hyperplasia, and the other includes early HCC and early advanced HCC. In order to evaluate the efficacy of transcatheter arterial embolization for treating such lesions, histopathologic studies were done after embolization and resection in 27 patients. MATERIALS AND METHODS: The lesions consisted of two adenomatous hyperplasias, one atypical adenomatous hyperplasia, 22 early HCCs, and 13 early advanced HCCs. All patients had chronic liver diseases in nontumorous parenchyma in addition to HCC. For transcatheter arterial embolization, one of the following embolizing materials was used: iodized oil (Lipiodol) alone (n = 4), an emulsion of doxorubicin in Lipiodol (n = 8), and the same emulsion followed by gelatin sponge particles (n = 15). RESULTS: The frequencies of tumor stain on the angiogram and retention of Lipiodol within the tumor were 84% and 94% in overt HCC, 23% and 69% in early advanced HCC, and 9% and 9% in early HCC, respectively. The average size of overt HCC was significantly (p < .01) larger than that of early advanced HCC and early HCC. The amount of necrosis induced by embolization relative to the size of the mass was 56% on average in overt HCCs, 14% in early advanced HCCs, and 0% in early HCCs, atypical adenomatous hyperplasias, and adenomatous hyperplasias. Significant differences (p < .01) in mean necrosis rate were seen between overt HCCs and early advanced HCCs, between early advanced HCCs and early HCCs, and between overt HCCs and early HCCs. The frequency of Lipiodol retention correlated with mean necrosis rate for tumor. With reference to therapeutic techniques, only for the overt HCCs was a significant difference (p < .01) in the mean necrosis rate found between the group that received the emulsion of doxorubicin in Lipiodol and the group that received the emulsion and then particles of gelatin. CONCLUSION: This study suggests that transcatheter arterial embolization has limited efficacy for treating early-stage HCC and borderline lesions compared with its efficacy for treating overt HCC.

Aged↗
PubMed1993

Combined hepatocellular carcinoma and cholangiocarcinoma: clinical features and computed tomographic findings.

Clinicoradiological features were studied in 20 patients with 22 mass lesions of combined hepatocellular carcinoma and cholangiocarcinomas and findings of computed tomography in 12 of these patients with 14 hepatocellular carcinoma-cholangiocarcinomas. Five of these patients also had single overt hepatocellular carcinomas. The incidence of hepatocellular carcinoma-cholangiocarcinoma was 3.3% among the patients with primary liver cancer treated in our hospital. HBsAg was present in 25%, and increased levels of serum alpha-fetoprotein (> 200 ng/ml) and carcinoembryonic antigen (> 5 ng/ml) were found in 25% and in 47%, respectively. Associated cirrhosis was present in 60%. Analysis of 14 hepatocellular carcinoma-cholangiocarcinomas in 12 patients in whom the enhancement pattern on dynamic computed tomography and pathological findings could be studied and compared suggested three tumor types. Nine lesions (type A) were demonstrated only as areas with high-density peripheries in the early phase of enhancement that evolved into a pattern of peripheral low density and central high density in the late phase. Four masses (type B) were shown as hyperdense tumors (early phase) that changed to low density in the late phase. One mass (type C) was seen as a low-density lesion that did not change. Histopathologically, type A comprised hepatocellular carcinoma-predominant components in the peripheral area, cholangiocarcinoma-predominant components with abundant fibrous stroma in the central area and a tissue transitional between the two in the midzone. By contrast, two of four type B masses comprised hepatocellular carcinoma with scattered cholangiocarcinoma components throughout the tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Hepatocellular carcinoma with portal tumor thrombus: analysis of factors determining prognosis.

For 104 consecutive patients with hepatocellular carcinoma (HCC) with portal tumor thrombus (PTT) seen in the past nine years, prognostic factors were analyzed retrospectively using Cox's multivariate analysis. There was a significant difference in survival rate with hepatic functional reserve (Child classification, P = 0.005), type of treatment (surgical vs non-surgical treatment, P = 0.009) and PTT grade (P = 0.04). The survival rates for patients with Child's A (n 49) or Child's B (n 55) were 60.8 vs 20.0% at one year, 41.6 vs 9.1% at two years and 35.4 vs 5.5% at three years. The survival rates of patients with surgical (n 32) and non-surgical (n 72) therapy were 71.7 vs 25.0% at one year, 58.5 vs 9.4% at two years and 53.6 vs 4.7% at three years. Among patients with PTT grades in the third or lower order branch (Vp1, n 29), the second order branch (Vp2, n 32) and the first or portal vein trunk (Vp3, n 43), the one-year, two-year and three-year survival rates were 61.6, 43.8 and 20.9%; 47.1, 27.5 and 6.2% and 42.8, 27.5 and 0%, respectively. When analysis was focused on 32 patients with Child's A and PTT (Vp1 plus Vp2) with respect to treatment, the survival rates in the surgical (n 22) and nonsurgical (n 10) groups were 86.1 vs 70.0% at one year, 71.5 vs 30.0% at two years and 64.3 vs 20.0% at three years (P < 0.05), respectively. In HCC patients with PTT, surgery seems to be indicated where hepatic function is well preserved and the PTT is localized in a peripheral portal branch.

Adult↗
PubMed1993

Helical computed tomography scanning of the thorax and abdomen.

We applied helical CT to examinations of the abdomen and thorax. Scanning was performed continuously while the couchtop of the CT scanner was shifted at a constant speed. The entire lung field could be scanned during a single holding of the breath when the couchtop speed was 20 mm/s. Tumors as small as 3 mm were detected. The diagnostic detectability and accuracy of helical CT were far superior to those of conventional chest radiography. During abdominal examination, the target organ could be scanned at any specified phase (preferably arterial) during the injection of contrast medium. We detected very small hepatic tumors which could not be detected by conventional CT. Helical CT produced continuous data, which was reconstructed to display three-dimensional images. Helical CT could be used in mass screening for the detection of early lung cancer and in computer-aided diagnosis.

Abdominal Neoplasms↗
PubMed1992

Postresection recurrence of hepatocellular carcinoma treated by arterial embolization: analysis of prognostic factors.

Of 270 consecutive patients with hepatocellular carcinoma who underwent surgery, 50 who had recurrence and were subsequently treated with transcatheter arterial embolization were analyzed. The longest interval between surgery and recurrence in the 50 patients who underwent transcatheter arterial embolization was 7 yr. Recurrence was initially found in the remnant liver in all patients but one; extrahepatic metastases were detected in 13 patients (26%) during follow-up. A "multiple" type was the most common (64%) hepatic recurrence pattern on angiography, followed by the "solitary" (16%) and "tumor thrombus" (12%) patterns. Hepatic recurrence was most frequently found in the ipsilateral lobe (48%) relative to the site of the primary hepatocellular carcinoma. Multivariate analysis of the factors affecting survival after transcatheter arterial embolization indicated that recurrence pattern (p = 0.025) and distant metastases (p = 0.011) were significant. Of 13 patients with distant metastases, 11 had the "multiple" pattern of hepatic recurrence. Survival rates for all 50 patients after initial surgery and after transcatheter arterial embolization were 90% and 64%, respectively, at 1 yr; 52% and 24%, respectively, at 3 yr; and 27% and 5%, respectively, at 5 yr. On analysis of survival rates after transcatheter arterial embolization in 37 patients with recurrence only in the liver and of the response of recurrent hepatocellular carcinoma to transcatheter arterial embolization, a significant difference was noted between those with "partial response" and "progressive disease" (p less than 0.05) and between those with "no change" and "progressive disease" (p less than 0.05).

Adult↗
PubMed1991

[Imaging diagnosis of small hepatocellular carcinoma by CT during arterial portography and Lipiodol-CT].

To evaluate the rates of detection for CT during arterial portography (CTAP) and Lipiodol-CT in small hepatocellular carcinoma (HCC), including early stage HCC, a comparative prospective study was performed in 24 candidates for surgery with 39 histopathologically proved lesions: eight lesions of early HCC, four of early advanced HCC and 27 of advanced HCC. The following results were obtained. 1) Ten of 24 patients had multiple primary HCC foci, 70% of which were, moreover, located in different segments. 2) Detection rates for digital subtraction angiography (DSA), CTAP and Lipiodol-CT were 67%, 87% and 72%, respectively. For 13 lesions undetected by DSA, the detection rates for CTAP and Lipiodol-CT were 62% and 31%. 3) For small HCC (n = 16) of less than 2 cm in diameter, CTAP (75%) tended to be superior to Lipiodol-CT (44%). 4) For early HCC (n = 8), CTAP (63%) showed a significantly higher detection rate than Lipiodol-CT (25%). 5) In contrast, detection rates for small (less than or equal to 2 cm) early advanced (n = 3) and advanced HCCs (n = 5) were almost the same: 67% and 100% by CTAP and 67% and 80% by Lipiodol-CT, respectively. To diagnose multiple primary HCCs in a candidate for surgery, CTAP is imperative following angiography.

Aged↗
PubMed1991

[Clinical application of helical scanning CT of upper abdomen].

The helical scanning CT unit, in which an X-ray tube continuously rotates at the rate of one revolution per second with constant movement of the table on which the patient is placed, was clinically tested in scanning of upper abdomen. Quality of the images obtained was equal to that of conventional CT. The images were particularly good at an X-ray beam width of 5 mm and table movement of 5 mm/sec with scan parameters of 120 kvp, 200 mA. Because of limitation of the X-ray tube capacity. X-ray beam width of 5 mm and table movement of 10 mm/sec with scan parameters of 120 kvp, 150 m, would be the most appropriate clinically. Application of the helical scanning CT will result in examination times shorter than in the case of conventional high-resolution CT and be obtained images at early vascular enhancement phase through the whole scanning area, so that it can be expected to be extremely useful in clinical diagnosis involving upper abdomen.

Adult↗
PubMed1990

Detection of hepatocellular carcinoma: comparison of CT during arterial portography with CT after intraarterial injection of iodized oil.

Fourteen patients with hepatocellular carcinoma (HCC) were examined with computed tomography (CT) during arterial portography (CTAP) and with CT after intraarterial injection of iodized oil. The detectability of main lesions and associated daughter nodules or intrahepatic metastases was assessed. Hepatic resection was subsequently performed in all 14 patients. The results of the imaging studies were compared with the surgical and pathologic findings by means of a lesion-by-lesion analysis. A total of 34 masses were identified in the resected specimens: 18 main tumor masses and 16 intrahepatic metastases. For CTAP, the detection rate of main tumors was 94%; for iodized-oil CT, 82%. However, the daughter-nodule detection rates for both techniques were poor-only 38% detected for CTAP and 50% for iodized-oil CT. Although these two techniques remain important preoperative imaging methods in patients with HCC, the results of this study suggest that small daughter nodules (less than 5 mm in diameter) may go undetected with both techniques.

Aged↗
PubMedDate not supplied

Findings in primary hepatic carcinoid tumor: US, CT, MRI, and angiography.

Two asymptomatic patients with surgically proven solitary primary hepatic carcinoid tumors are reported. Ultrasonography showed hyperechoic masses containing multiple small cystic areas in both cases. On unenhanced CT, one tumor was of low density and one was isodense with multiple low density foci. One tumor showed marked retention of contrast medium on post-angiographic CT. Magnetic resonance imaging revealed low intensity masses on T1-weighted images and high intensity tumors with multiple areas of higher intensity on T2-weighted imaging. The small low density areas in these masses corresponded histopathologically to multiple vascular lakes. Late enhancement of the mass was presumed to correspond with proliferative fibrous tissue within the mass.

Adult↗
PubMedDate not supplied

CT of lymphoepithelial cysts of the pancreas.

OBJECTIVE: To clarify imaging and clinicopathologic features of lymphoepithelial cysts (LEC), a benign lesion of the pancreas. MATERIALS AND METHODS: Two male patients with LECs that were found incidentally and proven surgically were reviewed. RESULTS: Sonography revealed a hypoechoic mass in both cases, one of which had septation and an intracystic isoechoic component within it. The mass was shown as low attenuation on unenhanced CT, and the intracystic solid component was not enhanced by dynamic CT or computed tomographic arteriography. One lesion had calcifications around the mass. Magnetic resonance imaging showed hyper- in hypointensity on T1-weighted imaging and hypo- in hyper- on T2-weighted imaging in one case. Both lesions were located on the surface of the head of the pancreas, and the main pancreatic ducts appeared normal on endoscopic retrograde pancreatography. Both patients were asymptomatic. CONCLUSION: These imaging and clinical findings suggest LEC, which should be considered when one encounters cystic lesions of the pancreas.

Humans↗