24 週間投与によりウイルス学的著効(sustained virological response，SVR) を得た．その後も肝機能は正常化していたが，2013 年 1 月スクリーニング 目的で行われた腹部超音波検査にて肝 S8 に径 15 mm 大の腫瘍を認めた． 腹部造影超音波検査， EOB 造影 MRI にて肝細胞癌と診断し，肝動脈塞栓術，ラジオ波焼灼術を施行した．IFN 治療に よる SVR 後 20 年を超えて肝細胞癌を発症した例はこれまで報告がなく， 肝硬変症例に対しては SVR 後も長期間の慎重な経過観察が必要であると思われた． 索引用語： 肝細胞癌 C型肝硬変 インターフェロン SVR 長期間 はじめに C 型慢性肝炎， 肝硬変に対するインターフェロン (IFN) 治療によりウイルス学的著効 (sustained virological response，SVR)が達成されると，炎症の鎮静化が得ら れ，肝細胞癌(hepatocellular carcinoma，HCC)の発 症リスクは有意に低下する １) -６) ．しかし，近年 SVR 達成後に HCC を発症した報告が増加している． 多くの 場合 SVR 後 10 年以内の発症とされているが，11-18 年経過して発癌した報告も散見される ７) -１ ０) ． 今回我々は SVR20

症例は59歳，男性．C型肝炎にて加療中にS6の2 cm大の肝細胞癌（HCC）が発見され，マイクロ波凝固療法を他院にて施行したが肝内多発再発を認め当院に紹介となった．肝動脈化学塞栓療法，sorafenib，リザーバー肝動注化学療法（low-dose FP療法），肝動注化学療法（CDDP），S-1内服投与を繰り返し行うも腫瘍は増大傾向でAFP 84352 ng/ml，PIVKA-II 25700 mAU/mlまで腫瘍マーカーも上昇した．ペグインターフェロン（Peg-IFN）α-2a 180 μg週1回投与を開始しAFP，PIVKAIIとも低下傾向を示し，9カ月後にはAFP 368 ng/ml，PIVKAII 123 mAU/mlまで低下した．画像上も肝内腫瘍濃染の消失を認め，経過中に見られた肺転移もPeg-IFNα-2a治療開始11カ月後のCTでは消失した．しかし，S3の3 cm大のHCC再発を認めたため，肝左葉外側区域切除術を施行しAFP/PIVKAIIは正常化した．Peg-IFNα-2a単独投与を含む集学的治療が奏功した進行肝細胞癌の1例を経験した．

Aim: Recently, many diagnostic modalities have been developed for the detection of hepatocellular carcinoma (HCC). Of these, a less invasive and more accurate diagnostic procedure is desirable. This study was undertaken to compare combined dynamic multidetector row helical computerized tomography (MDCT) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) with combined CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) for the detection of hypervascular HCC.Methods: Forty-eight patients with 56 pathologically proved hypervascular HCCs (less than 5.0 cm in diameter) underwent dynamic MDCT and SPIO-enhanced MRI, as well as CTHA and CTAP. The images were reviewed by four independent and blinded readers on a tumor-by-tumor basis.Results: The mean areas under alternative-free response receiver operating characteristic curve (Az) for combined dynamic MDCT and SPIO-enhanced MRI (IV set) and combinedCTHA and CTAP (IA set) were comparable (0.948 and 0.969, respectively, P > 0.05), although the Az value of the IV set was significantly lower than that of the IA set in HCCs smaller than or equal to 1.5 cm (0.867 and 0.937, respectively, P = 0.033). The mean sensitivity and positive predictive value of the IV set were similar to those of the IA set.Conclusions: Combined dynamic MDCT and SPIO-enhanced MRI showed a diagnostic accuracy comparable to intra-arterial contrast-enhanced CT (CTHA and CTAP) for hypervascular HCC, and may be a useful diagnostic option prior to curative treatments of hypervascular HCC, although a limitation exists in detecting HCCs smaller than or equal to 1.5 cm.

Focused ultrasound surgery (FUS) is a method of noninvasive focal thermal ablation. Temperature-sensitive phase-difference magnetic resonance (MR) imaging allows monitoring of the focal point and measurement of tissue temperature elevation in real time, ensuring delivery of a therapeutic dose. A newly developed respiratory monitoring system enables us to track liver tumors, which move with respiration. We report our initial experience using MR-guided FUS with respiratory gating in successfully treating a hepatocellular carcinoma 15 mm in diameter.

OBJECTIVE:To find the optimal scan timing for early arterial phase hepatic CT with adequate arterial enhancement after the aortic contrast arrival. METHODS:Sixty patients were divided randomly into three groups, each of which received 2.0 mL/kg of the 300 mgI/mL contrast medium with an injection duration of 30 seconds (Group A, mean rate 3.6 mL/sec); of 25 seconds (B, 4.6 mL/sec); of 30 seconds (3.6 mL/sec) followed by a saline chaser (C). RESULTS:After the contrast arrival, aortic enhancement increased rapidly for 6-15 seconds (mean, 10 seconds) to the initial peak enhancement in all groups, and then, increased moderately to the maximum aortic enhancement over the following 19, 13, and 21 seconds, respectively. The mean maximum aortic enhancement in Group B (392 HU) and C (360 HU) were significantly higher than that in A (326 HU), respectively. The difference between the initial and maximum aortic enhancement was less than 50 HU. CONCLUSION:The optimal timing of the early arterial phase for hepatic CT arteriography is 10-15 seconds after the aortic arrival.

Focused ultrasound surgery (FUS) is a completely noninvasive, focal thermal ablation method. Various clinical applications of ultrasound-guided FUS have been investigated over the last five decades. However, three inherent challenges limited the clinical efficacy of FUS until recently : imprecise localization, inability to monitor temperature elevation at the focal point, and difficulty evaluating the procedure's success during or immediately after treatment. Recent advances in magnetic resonance (MR) imaging have resolved these problems. Pretreatment MR images enable precise target definition and treatment planning. Temperature-sensitive phase-difference MR imaging can monitor the focal point and measure tissue temperature elevation in real time, ensuring delivery of a therapeutic dose. Posttreatment gadolinium-enhanced MR images provide immediate assessment of the treatment's success. In this article we review the principles, therapeutic methods, and clinical applications of MR image-guided FUS.

Background: Changes in body fat mass in a large number of hemodialysis patients is unknown. Methods: Body fat mass and lean body mass were measured by dual x-ray absorptiometry (DXA) in 561 patients with hemodialysis duration less than 180 months (62.3 +/- 11.5 years old; mean +/- SD). Results Fat mass tended to increase during the first 3 years of hemodialysis, and it tended to decrease thereafter. Between hemodialysis duration and the fat mass index, there was a significant positive correlation within the first 36-month period of hemodialysis (r = 0.124; P < 0.05; n = 245), and a significant negative correlation during the period of 36 to 180 months. (r = -0.192; P < 0.001; n = 316). There was no tendency of change in the lean body mass index. Conclusion: Considering the results together with the authors previous prospective study results, which show significant fat mass increase in the first year of hemodialysis, the present cross-sectional study may suggest that fat mass gradually increases in the first 3 years and decreases thereafter. Fat mass is suggested to be a nutritional parameter in hemodialysis patients.

We examined a new MR technique for obtaining 3D-MRA images of the liver that simultaneously depicts HCC and the portal and hepatic veins. Five patients with clinically suspected HCC were studied with superparamagnetic iron oxide (SHU-555A) used as a negative contrast medium for the liver. In our study, a 3D-rotational display was provided on the CTR monitor from 2D-TOF images by computed reconstruction, clearly showing HCC and portal and hepatic veins on the same image. Our method was found to be of great value in planning surgery of the liver.

Acalculous cholecystitis occurred in a patient with Weber-Christian disease. It reflected a panniculitis similar to that which developed in the orbit, abdominal cavity, and the retroperitoneal space.

In this study, we investigated the relationship between TAE frequency and its effectiveness. TAE was ineffective in 11 of 15 patients who underwent TAE 4 times or more, although earlier TAE had been clearly effective in all of them.Two different patterns of resistance to TAE were observed, i.e. collateral arterial supply (epicholedochal plexus in most cases) and conversion of an expanding tumor to an infiltrating tumor. To avoid the former, it is important not to cause intimal injury in the proximal arteries during TAE procedures. In the latter case, use of new anti-cancer drugs may be effective.

Adrenal venous blood samples drawn before and after stimulation with adrenocorticotropic hormone (ACTH) were analysed in 32 consecutive patients with primary aldosteronism. Twenty-six patients had aldosterone-producing adenomas and six patients had bilateral hyperplasia.

An MR study was performed in 73 clinically diagnosed cirrhotic patients to determine correlations among the demonstration of small low intensity nodules (SLINs), secondary changes due to cirrhosis, and serological data. In 32 patients, liver cirrhosis was proved histologically. SLINs were observed in 38 of the 73 patients on gradient echo (GRE) images and in 28 patients on T2-weighted SE images. Patho-MR correlation study of the liver in the 32 histologically proved cirrhotic patients revealed that SLINs were seen on GRE images only in patients with iron deposits in regenerating nodules (RNs). There was no significant correlation between secondary changes due to liver cirrhosis and the demonstration of SLINs. Serological data indicating liver cell injury and iron store in the body were significantly higher in patients with iron deposits in RNs than in those without iron deposits.

Thirty-eight patients with focal liver tumors (20 hepatomas, 18 hemangiomas) were studied by dynamic sequential inversion recovery (IR) snapshot fast low angle shot (FLASH) MR imaging with Gd-DTPA. Immediately after 0.05 mmol/kg Gd-DTPA was administered intravenously for 2-3 s followed by flushing with normal saline for 4-5 s, 10 images were obtained in the first 20 s (time zero is the end of flush, early phase). Then, one image every 30 s from 1 to 3 min (late phase) and images at 5 min and 7 min (delayed phase) were obtained serially. Hepatomas showed total enhancement in 18 of 20 patients in the early phase, and isointense or low intensity enhancement with respect to the surrounding liver parenchyma in 18 patients in the late to delayed phases. Hemangiomas showed peripheral enhancement in 14 patients in the early phase, but did not show total enhancement (except for two hemangiomas less than 3 cm in size) in the early phase, and showed high intensity enhancement in 15 patients in the late phase. Ninety percent of hepatomas and 82% of hemangiomas showed their characteristic enhancement patterns in the early to delayed phases. We conclude that dynamic sequential IR snapshot FLASH MR images enhanced with Gd-DTPA can facilitate differentiation between hepatomas and hemangiomas.