Kohichi Shimizu

Prognostic factors of hepatocellular carcinoma in patients undergoing hepatic resection

BACKGROUND/AIMS Prognostic analysis on hepatocellular carcinoma (HCC) in patients undergoing hepatectomy is necessary to determine the clinical value of hepatectomy on prognosis. METHODS Survival and disease-free survival were analyzed in 104 HCC patients undergoing hepatectomy using clinicopathologic factors by univariate and multivariate analyses. The value of the International Union Against Cancer (UICC) TNM classification on prognosis was assessed in the patients. RESULTS In multivariate analysis, portal vein invasion was the most influential factor. The difference between stage 1 and 2 or stage 3 and 4A using UICCs TNM classification was not significant with respect to survival or disease-free survival. The UICCs classification was modified as follows; stage 1, solitary tumor without vascular invasion; stage 2, solitary or multiple tumor(s) involving adjacent to vessel branch; stage 3, tumor(s) involving major vessel branch or with regional lymph nodal metastasis; and stage 4, tumor(s) with distant metastasis. The differences between each stage in the modified classification were significant with respect to disease-free survival. CONCLUSIONS The UICCs TNM classification was not of prognostic significance. Further studies on survival in patients with HCC are necessary to evaluate the value of the UICCs TNM classification; some modification may be necessary.

Hepatic resection using a water jet dissector.

A newly-designed water jet dissector was used for hepatic resections in humans. To evaluate its usefulness, the water jet dissector was compared toan ultrasonic surgical aspirator in terms of average blood loss and time of operation. In hepatectomies on patients associated with liver cirrhosis, the average blood loss during hepatic resection using the water jet dissector was significantly smaller (P<0.05) than that with the ultrasonic surgical aspirator. However, in hepatectomies on patients without cirrhosis, the average blood loss during hepatic resection did not significantly differ between the two groups. Neither did the time of operation significantly differ between the two procedures in hepatectomies on patients with and without liver cirrhosis. No serious complications attributable to the use of the water jet dissector were encountered. The water jet dissector is thus considered to be a useful new device for use in the transection of the liver during hepatic resections.

Angiomyolipoma mimicking true lipoma of the liver: Report of two cases

Hepatic angiomyolipoma (AML) is very rare and only about 80 cases have been reported. The tumor is fundamentally heterogeneously composed of the three tissue components of blood vessels, smooth muscle cells (SMC), and fat cells. Two cases of hepatic AML are reported here, both of which are histologically composed predominantly of a fat cell element and resembled true lipoma (lipomatous AML). However, careful examination of both tumors revealed the presence of a small amount of epithelioid SMC, especially around blood vessels. Immunohistochemical study using monoclonal antibody for melanoma (HMB‐45) clearly revealed a small amount of HMB‐45‐positive SMC around the blood vessels and scattered in the diffuse fat cell growth in both tumors. Since no liver tissue components or primary liver tumors are reactive with HMB‐45 except AML cells, the presence of HMB‐45‐positive cells within the tumor clearly established the diagnosis of hepatic AML Any fatty tumor or focal fatty lesion of the liver that superficially resemble true lipomas should be tested for the presence of HMB‐45‐posi‐tive SMC in the tumor to differentiate it from AML.

Angiomyolipoma of the liver: Its clinical and pathological diversity

Eighty cases (82 tumors) of hepatic angiomyolipoma (AML) from the world literature were reviewed, including our 8 cases. The tumors occurred predominantly in females (female: male ratio, 56∶24). Only six patients (7.5%) had associated tuberous sclerosis. The majority of the tumors (95%) occurred in non-cirrhotic, almost normal liver. The tumors usually presented as a hyperechoic mass on ultrasound (US) examination, a hypodense mass on computed tomography (CT) scan, and hyperintense mass on both T1- and T2-weighted magnetic resonance (MR) imagings. However, the imaging features of the tumor were occasionally variable according to the content of fat tissue component, and the tumors could not be clearly differentiated from other hepatic tumors, particularly hepatocellular carcinoma (HCC), based on the imaging features alone. Tumor location was recorded in 81 tumors; 44 were located in the right lobe, 30 in the left, 5 in the caudate, and 2 in both lobes of the liver. The tumor diameter ranged from 0.3 to 36cm (mean, 8.0±7.0cm). Macroscopically, the tumors usually had no fibrous capsule. The cut surface was yellow to dark brown depending on the amount of fat tissue or blood vessels. The histologic features were quite variable and occasionally included atypical and/or pleomorphic cells, which could lead to the erroneous diagnosis of a variety of benign and malignant tumors, including lipoma, leiomyoma, HCC, hepatoblastoma, leiomyosarcoma, and malignant fibrous histiocytoma. Extramedullary hematopoiesis was found in 33% of the tumors. Reactivity of the tumor cells of the liver with HMB-45, a melanoma-specific antibody, can accurately establish the diagnosis of AML.

The immunosuppressive effect of 5-lipoxygenase inhibitor on liver allotransplantation in rats

This study was performed to examine the immunosuppressive effect of a 5-lipoxygenase inhibitor, AA-861, on liver transplantation in rodents, and also to examine the production of eicosanoids during rejection of liver allograft in these animals. Rats were divided into three groups: group I (syngenic orthotopic liver transplantation from LEW to LEW), group II (allogenic OLT from ACI to LEW with dimethyl sulfoxide), and group III (allogenic OLT from ACI to LEW with AA-861 [20 mg/kg/day] s.c. dissolved in DMSO). Histological examinations were performed, survival time was monitored, and eicosanoid levels at 3, 5, and 7 days after transplantation were measured. Mean survival time in group III was significantly longer than that in group II (36.0 +/- 6.8 vs. 11.1 +/- 0.7 days, mean +/- SEM; P < 0.01). Histologically, the degree of rejection in group III was moderate compared with that in group II. On day 3, the LTB4 level in group II was significantly higher than that in group I (3361 +/- 985 vs. 407 +/- 70 pg/ml, P < 0.05), and the PGE2 level in group III was significantly higher than that in group 1 (50.3 +/- 4.8 vs. 23.5 +/- 4.7 pg/ml, P < 0.01) and in group II (32.9 +/- 4.2 pg/ml, P < 0.05). These findings suggest that AA-861 reduced liver allograft rejection by suppressing the elevation of 5-lipoxygenase products and increasing PGE2 production in the early stage of rejection.

Pseudolymphoma (Reactive Lymphoid Hyperplasia) of the Liver Containing Epithelioid Cell Granulomas and Schaumann's Bodies in Giant Cells A Case Report

Nodular lymphoid hyperplasia, also known as pseudolymphoma (PL), of the liver is a benign reactive process of lymphoid tissue and is extremely rare. To our knowledge, only four cases of hepatic PL have been reported to date. We present a 59-year-old woman patient with hepatic PL that was preoperatively diagnosed as hepatocellular carcinoma (HCC), based on the findings of a variety of imaging modalities. However, resection of the tumor specimen at hepatic lobectomy revealed that the tumor was not a true tumor but a PL composed of proliferated nonneoplastic, polyclonal lymphocytes and plasma cells with abundant lymphoid follicles, together with mononuclear and multinuclear histiocytes with granuloma formation. Sporadic multinucleated giant cells had concentrically or eccentrically laminate ‘conchoidal’ bodies, known as Schaumanns bodies. Immunohistochemical staining of lymphocytes and plasma cells for T and B cells, or IgGK and IgGk revealed the polyclonal nature of these cells. Furthermore, clonal immunoglobulin heavy-chain gene rearrangement was not detected in the lymphoid cells in the lesion with polymerase chain reaction (PCR) analysis. The background hepatic tissue showed no cirrhosis, but some lymphocytes had infiltrated into the portal tracts around the tumor. Since hepatic PL is extremely rare and no association of PL with granuloma with Schaumanns bodies has been described in previously reported cases with hepatic PL, the clinical and histologic features in this case are described with a literature review.

Criteria of curability in the hepatectomy for hepatocellular carcinoma.

肝細胞癌切除例79例を対象に,肝癌取扱い規約に基づいた切除術式別及び腫瘍進展度の各因子別に予後を検討した.絶対的治癒切除術の生存曲線は相対的非治癒切除術及び絶対的非治癒切除術に比べ,また相対的治癒切除術の生存曲線は相対的非治癒切除術よりも有意に良好であった.腫瘍進展度では,予後に最も影響を及ぼす因子は門脈侵襲であった.相対的治癒切除術の中でも,腫瘍径によってT2となり相対的治癒切除術となった相対的治癒切除A群と,主として門脈侵襲による血管侵襲が陽性であるためにT2となり相対的治癒切除術となった相対的治癒切除B群,及び絶対的治癒切除術とでの予後の検討では,血管侵襲をみない絶対的治癒切除術及び相対的治癒切除A群の予後は血管侵襲を認めるB群よりも良好であった.血管侵襲を認める症例に対する肝切除術では,肝切除単独では治癒治療法にはなり難く,術後の綿密なfollow upとadjuvant chemotherapyの必要性が示唆された.