Etsuo Inoue

Clinical features of small hepatocellular carcinomas as assessed by histologic grades

BACKGROUND Ninety-seven patients with small hepatocellular carcinomas (HCCs) measuring 3 cm or less in size and three patients with adenomatous hyperplasia who underwent radical hepatic resection were examined in this study. METHODS The lesions were classified into four groups according to the following histologic grading criteria: group A, adenomatous hyperplasia (n = 3); group B, early HCC (n = 6); group C, well-differentiated HCC (wHCC) (n = 32); and group D, moderately or poorly differentiated HCC (n = 59). The involvement factors that seemed to be important or to characterize the progression of HCC and the survival rates were compared among the four histologic groups. RESULTS The frequency of patients with tumors larger than 2.0 cm in size and that of patients with 200 or more ng/ml serum alpha-fetoprotein increased with the progression of histologic malignancy. Tumor staining on the angiogram, capsular formation, and extranodular invasion were never seen in groups A and B, but they began to appear in group C and increased remarkably in group D. The 5-year survival rates of the patients in groups B, C, and D were 100%, 60%, and 27%, respectively, and statistically significant differences were seen among them. In comparative evaluation of the group C patients the lesions that showed no tumor staining had no capsule, and those that had no capsule had no extranodular invasion. The 5-year survival rate of patients with wHCC without extranodular invasion (81%) was significantly higher than that of patients with extranodular invasion (35%) (p < 0.05). CONCLUSIONS It may be recommended to provide the category of wHCC without extranodular invasion for pathologic classification of clinically early HCC (i.e., HCC of high curability).

Double Phase Ct Arteriography of the Whole Liver in the Evaluation of Hepatic Tumors

PURPOSE Our goal was to evaluate the contribution of double phase CT arteriography (CTA) of the whole liver to differentiate hepatic tumors from false-positive areas on CT during arterial portography (CTAP). METHODS In 38 candidates for surgical resection of hepatic tumors, both CTAP and double phase CTA were performed. A total of 68 perfusion defects were identified at CTAP. Of 68 perfusion defects, 47 were found to represent hepatic tumors [hepatocellular carcinoma (HCC), n = 31; hepatic metastasis, n = 13; cholangiocarcinoma n = 2; focal nodular hyperplasia, n = 1]. The other 21 perfusion defects were defined as perfusion abnormalities in which focal hepatic masses had not been identified at surgery or pathologic analysis. The phase one CTA scanning started 12 s after the beginning of the injection of contrast material, and the phase two CTA scanning started 20 s after the end of the phase one CTA, with 60 ml of contrast agent (150 mg I/ml) injected at a rate of 2 ml/s. RESULTS On phase one CTA, only 1 lesion in 31 HCCs showed rim enhancement and 26 HCCs (84%) had rim enhancement on phase two CTA. Twelve lesions (80%) of the hepatic metastases and cholangiocarcinomas had rim enhancement on phase one CTA and 11 lesions (73%) showed rim enhancement on phase two CTA. Twenty-one perfusion abnormalities on CTAP did not show rim enhancement on either phase one or phase two CTA. CONCLUSION Double phase CT arteriography of the whole liver was useful to differentiate hepatic tumors from perfusion abnormalities on CTAP.

Comparison between conventional and spiral CT in patients with hypervascular hepatocellular carcinoma

To determine the usefulness of spiral CT in the detection of hypervascular hepatic lesions, we compared conventional contrast enhanced CT (CECT) with whole liver dynamic scanning during the artery-dominant phase by spiral CT (SDCT), using hypervascular hepatocellular carcinoma (HCC) as a model. Twenty-nine patients with 56 hypervascular nodular type HCCs detected by hepatic digital subtraction angiography were examined by both CT techniques. These nodular type HCCs were divided into three groups according to diameter: < 10 mm (n = 7), 10-20 mm (n = 17), and over 20 mm (n = 32). None of seven lesions less than 10 mm in diameter was seen by either technique. Of 17 lesions 10-20 mm in diameter, four (24%) were detected by precontrast CT plus CECT, whereas 14 (82%) were detected by precontrast CT plus SDCT. There were no lesions detected by CECT only, whereas 10 lesions were detected by SDCT only (P < 0.01 by signed test). For 32 lesions over 20 mm in diameter, there was no significant difference in detection rates between the CT techniques. Our results indicate that spiral CT is useful for the detection of relatively small hypervascular hepatic lesions such as hypervascular HCCs.

MR features of various histological grades of small hepatocellular carcinoma

Twenty small hepatocellular carcinomas (HCCs) <20 mm in diameter in 18 patients, detected by MRI, were surgically resected and histologically confirmed. Quantitative analysis of signal intensity on MR images was performed with 14 homogeneous lesions. In the five grade I HCCs, T1-weighted SE sequences provided significantly higher mean tumor-liver contrast and contrast-to-noise ratio (C/N) than T2-weighted SE sequences (p < 0.01). However, in the other nine HCCs (grade I + II or greater), T2-weighted SE sequences had significantly higher mean tumor-liver contrast and C/N values than T1-weighted SE sequences (p < 0.001). The T2-weighted SE sequences appear superior to T1-weighted SE sequences for grade I + II or greater HCC detection, whereas T1-weighted SE sequences are valuable in the detection of grade I HCCs.

Indications for hepatectomy for hepatocellular carcinoma : What stage of the disease is the best indication for surgery?

To determine the clinical and tumor stage of hepatocellular carcinoma (HCC) that is the best indication for surgery, the postoperative long-term outcomes of patients who underwent hepatic resection were examined retrospectively. Of 975 patients with HCC who underwent regional therapy, 384 patients (39%) received hepatic resection (HR), 534 (55%) had transcatheter arterial chemoembolization (TACE), and the remaining 57 (6%) received percutaneous ethanol injection (PEI) into the tumor. The criteria defined by liver Cancer Study Group of Japan was used for staging and liver functional reserve (i.e., clinical staging). In the 133 patients with stage I HCC, there were no significant differences among the survivals of the HR, TACE, and PEI groups. In the 314 patients with stage II HCC, the 5- and 7-year survival rates were 51% and 46% in the HR group, 23% and 10% in the TACE group, and 0% and 0% in the PEI group. The survival of the HR group was significantly better than the survivals of the TACE and PEI groups (P < 0.001). The 5- and 10-year survivals of the stage II HCC patients who had HR were 64% and 47% in the clinical stage I (i.e., good liver function) group, significantly better than the 5; and 10-year survivals (32% and 23%) in the clinical stage II (i.e., bad liver function) group (P < 0.0001). Patients with good liver function in stage II are expected to have better survival and are considered to be the most suitable for HR.

MAGNETIC RESONANCE IMAGING-HISTOLOGIC CORRELATION OF SMALL HEPATOCELLULAR CARCINOMAS AND ADENOMATOUS HYPERPLASIAS

RATIONALE AND OBJECTIVES.Hepatocellular carcinomas (HCCs) usually consist of components of different histologic grade. Using surgically resected specimens, the authors obtained high-resolution magnetic resonance (MR) images and studied the relationship between histologic grade of HCCs and MR signal intensity. METHOD.In vitro MRI was performed on 15 small (less than 20-mm diameter) HCCs and 2 patients with adenomatous hyperplasia (AH) within 1 hour of surgical resection. In these 17 lesions, 24 macroscopic nodular components corresponding to MR images were recognized pathologically. The difference in MR signal intensity was examined by using tumor/phantom (T/P) signal-intensity ratio. In addition, the correlations between signal intensity on MRI and histologic criteria for grading HCC were studied. RESULTS.On T2-weighted images, grade II HCCs had significantly greater T/P values than grade I HCCs (P < .01). There is the correlation (r = .88, P < .001) between nucleocytoplasmic (N/C) ratio and signal intensity of small HCCs and AHs on T2-weighted images. CONCLUSION.The N/C ratio is an important factor relating the signal intensity to the histologic grade of these lesions on T2-weighted images.

MR angiography of meningioma

The clinical evaluation of three-dimensional time-of-flight MR angiography was prospectively performed in 16 patients with intracranial meningioma. MR angiographic techniques used in this study both with and without gadopentetate dimeglumine made it possible to demonstrate the topographic relationship between the tumors and the neighboring vascular structures. MR angiograms were compared with available conventional angiograms. The three-dimensional enhanced MR angiograms were successful in depicting sinus involvement in greater detail in six patients than conventional angiography. In six patients, the feeding arteries of meningiomas were demonstrated with the unenhanced MR angiograms. However, MR angiograms failed to show small feeding arteries in three patients as delineated with conventional angiography. Arterial displacement was shown in nine patients. Venous drainage and collateral circulations were also visualized in four patients. Our results indicate that multiview MR angiograms noninvasively provide useful information for planning the surgical treatment of patients with meningioma.

Low-cost soft-copy display accuracy in the detection of pulmonary nodules by single-exposure dual-energy subtraction: Comparison with hard-copy viewing

This study endeavored to clarify the usefulness of single-exposure dual-energy subtraction computed radiography (CR) of the chest and the ability of soft-copy images to detect low-contrast simulated pulmonary nodules. Conventional and bone-subtracted CR images of 25 chest phantom image sets with a lowcontrast nylon nodule and 25 without a nodule were interpreted by 12 observers (6 radiologists, 6 chest physicians) who rated each on a continuous confidence scale and marked the position of the nodule if one was present. Hard-copy images were 7 × 7-inch laser-printed CR films, and soft-copy images were displayed on a 21-inch noninterlaced color CRT monitor with an optimized dynamic range. Soft-copy images were adjusted to the same size as hard-copy images and were viewed under darkened illumination in the reading room. No significant differences were found between hard- and soft-copy images. In conclusion, the soft-copy images were found to be useful in detecting low-contrast simulated pulmonary nodules.

Dye-Injection Method for Placement of an Infusion Catheter in Regional Hepatic Chemotherapy

PURPOSE To evaluate the usefulness of a dye-injection method in the placement of an infusion catheter and port via proximal branches of the axillary artery for hepatic infusion chemotherapy. MATERIALS AND METHODS Sixteen patients with surgically unresectable hepatic cancer underwent transfemoral hepatic arteriography. Then a 3-F coaxial catheter was inserted into a proximal branch of the left axillary artery. Dye injected through the coaxial catheter during the surgical procedure improved the visualization of the target branch. The coaxial catheter was also used as a guide for retrograde insertion through the target branch of an infusion catheter into the descending aorta. RESULTS In 13 of 16 patients (81%), catheterization was successful without exposure of the axillary artery. In these patients, the acromial-deltoid branch of the thoracoacromial artery was chosen as the target. CONCLUSION Injection of dye simplifies the surgical procedure for placement of a hepatic infusion catheter via proximal branches of the axillary artery. The depth and extent of incisions, as well as the risk of nerve injury, are reduced.

Unusual atrophic change after repeated arterial therapy for hepatocellular carcinoma: Report of a case

We report the case of a 45-year-old man with advanced hepatocellular carcinoma (HCC) who was able to undergo radical surgery after repeated transarterial therapy. Transarterial chemoembolization was repeated three times, and thereafter, transarterial infusion chemotherapy using Lipiodol was performed on the right hepatic artery. Because notable atrophy of the right lobe and compensated hypertrophy of the left lobe were detected after this therapy, an extended right lobectomy could be performed. Histologically, the HCC showed complete necrosis. The remarkable atrophic change of the right lobe was thought to be due to an obstruction of the right portal veins by the spread of inflammation around the bile duct necrosis, in addition to the narrowing of the hepatic artery. A thorough understanding of this phenomenon and the development of methods to clinically apply it in the treatment of cancer patients may thus lead to an increase in the percentage of resectable cases of advanced HCC.