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Biomedical subjects

K Takayasu

Publications and source records attributed to K Takayasu.

At least 73 records · Page 4Linked to original sources
PubMed1990

Malignant transformation of adenomatous hyperplasia to hepatocellular carcinoma.

To clarify the course of adenomatous hyperplasia (AH) of the liver, 17 patients with 20 biopsy-proven AH nodules were followed clinically for 1-5 years. At the initial biopsy the mean nodular diameter was 10 (SD 4) mm and the relative cellularity [( mean cellularity of AH divided by mean parenchymal cellularity] x 100) 141 (27). The criteria for diagnosis of malignant transformation of AH were both a doubling of nodular volume and changes on imaging. Between 6 and 50 months after biopsy, 9 of the 18 nodules which could still be accurately identified met the criteria for transformation; histological proof of hepatocellular carcinoma (HCC) was obtained later for 7 of these 9 nodules. The product of diameter and cellularity (transformation index) was the strongest predictor of the time to transformation. 9 AH nodules did not undergo transformation--7 did not meet one or both criteria and 2 became undetectable by imaging. Because of the high risk of malignant transformation, it can be concluded that AH is an absolute precursor of HCC. It should therefore be treated as a potential malignant disorder.

Adenocarcinoma↗
PubMed1990

[A comparative study of histopathological findings of resectable pancreatic carcinoma (t1, t2 cases) with ERCP and CT images].

The diagnosis of pancreatic carcinoma at early stage has been considered very difficult. Histopathological findings of resectable pancreatic carcinoma less than 4 cm in size (t1, t2 cases) have been compared with endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography (CT) images for the purpose of improving the diagnosis of pancreatic carcinoma. Twenty-six patients with pancreatic carcinoma less than 4 cm in size, who underwent surgery at the National Cancer Center Hospital from January 1980 to December 1988, were analyzed. The mean age of these 26 cases was 64 years (range of 45 to 78 years), with 13 males and 13 females. Pancreatograms were classified into 4 groups such as stenosis, tapering, obstruction and others, and this classification was compared with histopathological findings. However, ERCP classification showed no correlation with histopathological findings. CT images of the margins, characteristics and density of the tumor were compared with histopathological findings. There existed a good correlation between CT images and histopathological findings such as histological differentiation, macroscopic type of cut surface and INF. For an accurate diagnosis of pancreatic carcinoma, it is important that localization of the tumor is diagnosed first by ERCP and the characteristics of the tumor should be recognized by CT images.

Adenocarcinoma↗
PubMed1990

New plastic-coated coaxial catheter system for superselective hepatic catheterization: technical note.

With the use of a new improved coaxial catheter system, superselective hepatic catheterization has become easier. The improvements consist of a decrease in the outer and an increase in the inner diameters of the coaxial catheters from 0.98 to 0.96 mm and from 0.55 to 0.65 mm, respectively, and thickening of core guidewire material from 0.014 inch (0.35 mm) to 0.018 inch (0.40 mm). With this new catheter system, it is possible to inject contrast medium (iopamidol 300) at a higher rate (3 ml/sec) and gelatin sponge particles instead of gelatin powder for arterial embolization. The success rates for superselective catheterization using conventional (n = 10 procedures) and the improved coaxial catheter systems (n = 7) were 30% and 86%, respectively.

Catheterization↗
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↗
PubMed1990

CT of hilar cholangiocarcinoma: late contrast enhancement in six patients.

Hilar cholangiocarcinoma usually appears on CT scans as a low-density or isodense mass that abruptly obstructs converging dilated bile ducts. In four of six patients with histopathologically proved hilar cholangiocarcinoma who had late enhanced CT 8-15 min after dynamic CT, the lesion was seen as a high-density mass instead of the low-density lesion seen earlier on unenhanced and dynamic CT scans. The other two patients had ring enhancement with evidence of a thickened wall of the bile duct both on early and late enhanced CT scans. In the first four patients, carcinoma invaded the neighboring hepatic parenchyma and produced a mass, whereas in the last two, carcinoma was localized in the wall of the bile duct. Histopathologically, all lesions consisted of adenocarcinoma associated with a dense fibrotic tissue. As late enhanced CT shows hilar cholangiocarcinoma as a high-density mass, the exact location of the tumor and its relation to neighboring vessels can be determined, especially in relatively small tumors, and differentiation from sclerosing cholangitis is possible.

Adenoma, Bile Duct↗
PubMed1990

The diagnosis of small hepatocellular carcinomas: efficacy of various imaging procedures in 100 patients.

The efficacy of various imaging procedures used for the diagnosis of small hepatocellular carcinomas (HCCs) (lesions no larger than 3 cm in diameter) was evaluated in a retrospective study of 100 patients. Seven patients with hepatic adenomatous hyperplastic nodules containing HCC foci were also assessed. In 89 patients, the lesion was initially detected during follow-up of chronic liver disease. In 21 patients, it was first diagnosed on the basis of elevated serum alpha-fetoprotein; in the remaining 79 it was diagnosed incidentally with imaging procedures. The overall sensitivities of sonography (84%), CT (84%), and angiography (81%) were compared with those of arterial angiographic CT (82%), portal angiographic CT (91%), lipiodol CT (93%), and intraoperative sonography (96%). The differences in sensitivity between angiography and lipiodol CT (p less than .05) and between intraoperative sonography and the other studies (p less than .01) were statistically significant. In 22 lesions smaller than 1 cm, the sensitivities of lipiodol CT and intraoperative sonography were high (83% and 86%, respectively). Adenomatous hyperplasias containing HCC foci were frequently detected by arterial angiographic CT and intraoperative sonography. These results show that sonography or CT and alpha-fetoprotein are useful in detecting small HCCs in screening programs of patients with chronic liver disease. Lipiodol CT and intraoperative sonography are necessary in patients who are candidates for surgery.

Adult↗
PubMed1990

Early diagnosis of hepatocellular carcinoma.

We describe the results of our study on the early detection of the development of hepatocellular carcinoma among patients with chronic liver disease. Over a period of 18 years, 33 patients were diagnosed as having hepatocellular carcinoma. From 1970 to 1978, we used serum alpha-fetoprotein determination, liver palpation, and radionuclide liver scans. In addition to alpha-fetoprotein determination, computed tomography and ultrasonography were introduced in 1979. However, we did not have any general guidelines for the use of these imaging modalities. From 1984 onwards, ultrasonography and serum alpha-fetoprotein determination have been performed every three months and computed tomography every year in patients whose right hepatic lobe had atrophied due to liver cirrhosis. On the basis of this screening program, 50% of the detected hepatocellular carcinoma (9/18) were found to be smaller than 1.9 cm in diameter, and tumor resection was performed in 11 out of 18 patients (61%).

Adult↗
PubMed1990

Resection after intraarterial chemotherapy of a hepatoblastoma originating in the caudate lobe.

A rare case of hepatoblastoma originating in the caudate lobe was treated successfully with intraarterial chemotherapy followed by extensive lobectomy of the left side of the liver. Imaging modalities demonstrated a solitary huge tumor, initially inoperable, occupying almost the entire liver in a 4-month-old female infant. Transcatheter intrahepatic arterial chemotherapy with 10 mg doxorubicin, 20 mg cisplatin, and 3 ml Lipiodol, repeated twice at a 1-month interval, led to a remarkable reduction in tumor size and thereby made it resectable. The volume ratio between the intact hepatic parenchyma and the tumor changed from 1:1.70 to 1:0.13, as assessed by serial computed tomography scans, and the patient's initial alpha-fetoprotein level of 223,210 ng/ml declined to 53 ng/ml. The present case is the first in the literature, to our knowledge, of a resected hepatoblastoma in the caudate lobe. Clinical details of the tumor and surgical issues are discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

[Evaluation of the efficacy of oil chemoembolization for hepatocellular carcinoma by computed tomography: a proposal for altering the criteria to indicate the efficacy].

To evaluate the efficacy of oil chemoembolization for hepatocellular carcinoma (HCC), the authors have investigated computed tomography (CT) and pathological findings of 29 resected HCCs from 24 patients and have reached the following conclusions: (1) HCCs that showed a dense retention of Lipiodol within the whole tumor or showed no enhancement on contrast enhanced CT had a significantly higher necrosis rate (p less than 0.01) but were not always easy to evaluate; and (2) in 18 of the 29 tumors that had been observed by CT for 4 to 8 weeks after oil chemoembolization, 91% of those tumors which had a high necrosis rate (greater than or equal to 90%) showed a significant reduction rate that was 20% or greater (p less than 0.05). Based on these results, we propose altering the criteria to allow for the indication of 'partial response', that is, a decrease of 20% or greater in the size of the tumor, confirmed by CT measurement within 8 weeks after oil chemoembolization, and no new lesions or signs of progression in any existing lesion.

Adult↗
PubMed1990

Aberrant right gastric vein directly communicating with left portal vein system. Incidence and implications.

In 3 patients with primary hepatic malignancies, a communication between the right gastric vein and the left portal vein system was recognized at angiography. The right gastric vein entered directly into the left lateral portal veins in 2 patients and into the left medial portal veins in one. Portal angio-CT performed in one patient demonstrated a specific defect only in the left lateral superior area of the liver, consistent with the segmental opacification of the portal vein branch recognized on the angiogram. This rare communication was seen in 3 (1.5%) of 200 consecutive patients who underwent celiac angiography and is most likely an anomaly in which the right gastric vein directly enters the left portal vein instead of the portal vein trunk. When interpreting a filling defect not associated with a mass lesion on portal angio-CT for hepatic neoplasms or the right gastric vein communicating with the left portal vein system on the angiogram, this particular anomaly should be considered.

Adult↗
PubMed1990

Preoperative portal embolization to increase safety of major hepatectomy for hilar bile duct carcinoma: a preliminary report.

Extensive liver resection for hilar bile duct carcinoma with jaundice has high morbidity and mortality rates because of postoperative liver failure. To minimize postoperative liver dysfunction, a portal venous branch was embolized before surgery to induce atrophy of the lobe to be resected and hypertrophy of the contralateral lobe in 14 patients with hilar bile duct carcinoma. Bile was drained before surgery in 11 patients with jaundice. Portal embolization did not produce major side effects, and moderate increases of serum transaminase activity or bilirubin returned to baseline values within 1 week. Hepatectomy with bile duct resection and lymphadenectomy was performed 6 to 41 days after embolization, at which time the embolized lobe was atrophied in 12 of the patients. Extended right or left lobectomy or left trisegmentectomy (10, 3, and 1 cases, respectively) with biliointestinal reconstruction was performed. One patient with jaundice and suppurative cholangitis died 30 days after hepatectomy. Another patient died 3 months after surgery of aggravated hepatitis. After surgery, no bile leakage occurred and hyperbilirubinemia was usually moderate and reversible.

Aged↗
PubMed1989

Clinical and radiologic assessments of the results of hepatectomy for small hepatocellular carcinoma and therapeutic arterial embolization for postoperative recurrence.

To study the prognostic significance of the state of the residual liver after hepatectomy for small hepatocellular carcinoma (s-HCC) no larger than 5 cm in diameter, 123 patients were followed for periods from 9 months to 9 years and 1 month. The following results were obtained: (1) recurrence occurred in the residual liver in 58 patients (54.2%) after an average of 14.9 months from hepatectomy; (2) at recurrence diagnosed by imaging, 12 of 48 recurrent patients showed negative alpha-fetoprotein; (3) computed tomography (CT) had a high sensitivity (71.4%) in detecting recurrence; (4) 5-year survivals for all patients (n = 123) who had hepatectomy, and for those without recurrence (n = 49) or with recurrence (n = 58) were 19.1%, 48.9%, and 11.0%, respectively; and (5) survivals for the patients who developed recurrence and who did and did not receive embolization treatment (n = 32, 23, respectively) were 70.3% and 37.1% at 1 year, 45.0% and 0% at 3 years, and 14.9% and 0% at 5 years, respectively. It is important to recognize that the patient who has undergone surgery even for s-HCC should be followed as a super high-risk patient at regular intervals using CT. Therapeutic embolization for recurrent patients improved the survival after recurrence.

Adult↗
PubMed1989

Evaluation of the prognosis for small hepatocellular carcinoma based on tumor volume doubling time. A preliminary report.

The relationship of tumor volume doubling time to length of patient survival was investigated for 15 patients with small hepatocellular carcinoma smaller than 4.5 cm in diameter. The mean tumor volume doubling time of these 15 nodules was 102 +/- 77 days (mean +/- SD; range 41 to 305 days) before the initiation of a specific treatment for cancer. These doubling times tended to correlate with mitotic indexes of the tumors and the patients could be divided into two groups according to the therapeutic modalities used. Patients in Group A received systemic chemotherapy without response or nonspecific treatments for cancer. In this group, there was a positive correlation between tumor volume doubling time and survival length (r = 0.8812; P less than 0.025). Patients in Group B either received hepatectomy after transarterial embolization or systemic chemotherapy or received hepatectomy alone. In this group, early death occurred in patients who had shorter tumor volume doubling times. Three surgically treated patients in Group B were evaluated as having survived for a significantly long period as assessed from their tumor volume doubling times. These results indicate that tumor volume doubling time is one of the determining factors of survival length in patients with hepatocellular carcinoma, and, therefore, can be used in the evaluation of therapeutic efficacy.

Aged↗
PubMed1989

Hepatic artery embolization for inoperable hepatocellular carcinoma; prognosis and risk factors.

During a 7-year period in our hospital, 69 patients with inoperable hepatocellular carcinoma (HCC) underwent 111 courses of transcatheter hepatic artery embolization (TAE) and/or chemoinfusion with lipiodol. Patient survival was 0.5-37 months following therapy and the factors affecting prognosis were evaluated. Survival rates at 1, 2 and 3 years after TAE were 53%, 24% and 15%, respectively. Survival rates at 1, 2 and 3 years in relation to tumor size were 100%, 100% and 100% in 5 patients (tumor size less than 2 cm in diameter), 81%, 33% and 16% in 23 patients (2.1-5.0 cm), and 35%, 9% and 0% in 41 patients (greater than 5.1 cm). An analysis of prognostic factors showed that the size of the main tumor significantly influenced the prognosis following TAE (P less than 0.01), whereas the frequency of TAE, intrahepatic metastasis and the degree of liver dysfunction showed a slight correlation (P less than 0.1). These results suggest that TAE has a significant potential for becoming the first choice of treatment for patients with small multiple HCCs (less than 2 cm), provided that neither severe hepatic dysfunction nor a tumor thrombus in the main portal vein is present.

Adult↗
PubMed1989

Imaging diagnosis of portal tumor thrombus secondary to gastric cancer.

Tumor thrombus in the portal vein secondary to advanced gastric cancer was diagnosed by ultrasound (US) and computed tomography (CT), and was confirmed at autopsy in a 54-year-old man. The register data for 3176 patients of resected gastric cancer disclosed that there was no patient with portal tumor thrombus secondary to gastric cancer.

Budd-Chiari Syndrome↗
PubMed1989

Transient perihilar attenuation difference in the liver on dynamic CT secondary to portal vein thrombosis: report of two cases.

In two patients with portal vein thrombosis (PVT) accompanied by cavernous transformation, transient perihilar attenuation difference (TPAD) was demonstrated in the liver in the arterial phase of dynamic CT. It changed to an isodense shadow in the late phase. In one case, the area demonstrated as TPAD was well enhanced by postarterial portal CT, and in the other case, perihilar region was also densely opacified as contrasted by the peripheral area which was enhanced slightly with postarterial portography. It suggested that the TPAD area well supplied by portal blood flow via cavernous transformation and that the peripheral area surrounding TPAD was mainly supplied by increased hepatic arterial blood compensating for reduced portal flow. When the TPAD is found in the early phase of dynamic CT scan, attention should be paid to the existence of portal vein thrombosis (PVT). Chronic pancreatitis was the likely cause in one patient, and in the other it was idiopathic.

Female↗