Akitaka Nonomura

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.

Angiomyolipoma of the liver: A collective review

This review summarizes the clinical and pathological findings of 52 cases of hepatic angiomyolipoma to discern and establish the most pertinent clinical and pathologic characteristics of the tumor. The disease was symptomatic in 60% of the patients. Abdominal pain or distress was the most common symptom, appearing in 37% of the patients, followed by malaise and upper abdominal mass or hepatomegaly. Of the 52 patients, only three (5.8%) showed associated tuberous sclerosis. Antemortem diagnosis of the tumor has been made with increasing frequency with the recent advent of computed tomography (CT) and ultrasound (US). The tumor was usually visualized as a hyperechoic mass by US imaging and as a low density mass less than -20 Housefield units by CT, and was hypervascular on angiography. The tumor was usually yellow to light tan, depending on the amount of fat tissue. Histologically, the tumor was characterized by an admixture of mature fat cells, blood vessels, and smooth muscle cells, with occasional foci of extramedullary hematopoiesis. The aumount of smooth muscle component varied and often exhibited hypercellularity, pleomorphism with occasional bizarre giant cells, and moderate mitotic activity. These features are considered conducive to an erroneous diagnosis of malignant tumor. However, since no malignant counterpart has been reported, it can easily be accurately differentiated histologically, if one is aware of the entity and can identify the three components of the tumor; blood vessels, smooth muscle cells, and fat. With regard to the histogenesis of angiomyolipoma, primitive mesenchymal cells around blood vessels may be the precursor cells.

Histopathology of the liver in non-cirrhotic portal hypertension of unknown aetiology.

Non‐cirrhotic, long‐standing portal hypertension of unknown aetiology is being re‐evaluated histopathologically and clinically. In this study, we examined 107 livers with this condition (92 wedge biopsy and 15 autopsy specimens) from five institutions in Japan. These cases were histologically categorized into four groups: idiopathic portal hypertension (66 cases), nodular regenerative hyperplasia (14 cases), partial nodular transformation (two cases), and incomplete septal cirrhosis (25 cases). These four groups shared several histological features: dense portal fibrosis with portal venous obliteration and intralobular slender fibrosis. In addition, the histopathological features characteristic of one group were also found to a mild degree in other groups. The histopathological lesions preceding portal venous obliteration remain speculative. However, the portal venous obliteration may be responsible for the occurrence of sustained portal hypertension and several of the pathological changes in these livers. It seems likely that idiopathic portal hypertension, nodular regenerative hyperplasia, partial nodular transformation and incomplete septal cirrhosis comprise a family of non‐cirrhotic, long‐standing portal hypertension in Japan, and the histological differences between them may reflect chronological progression of a single disease.

PRIMARY PULMONARY ARTERY SARCOMA. Report of Two Autopsy Cases Studied by Immunohistochemistry and Electron Microscopy, and Review of 110 Cases Reported in the Literature

Two cases of primary pulmonary artery sarcoma are reported. The patient in the first case was a 61‐year‐old male with a two‐year history of cough and exertional dyspnea, who died of intractable cardiac failure two months after admission without establishment of a diagnosis related to the etiology of cardiac failure. Autopsy revealed a sessile tumor within the pulmonary trunk and a solitary metastatic lesion in the lung. Histologic, immunohistocyto‐chemical and electron microscopic studies were performed and a diagnosis of malignant mesenchymoma was made. The patient in the second case was a 32‐year‐old male complaining of exertional dyspnea and back pain. Radiologic studies indicated a mediastinal tumor involving the pulmonary artery. Exploratory thoracotomy revealed that the mediastinal mass arose from the left pulmonary artery. He died of respiratory failure 26 months after onset of his initial symptoms. Histologic, immunocytochemical and electron microscopic studies of both surgical and autopsy materials revealed a malignant fibrous histiocytoma. One hundred ten previously reported cases of this tumor are reviewed, and its clinicopathologic and morphologic features and probable histogenesis are discussed. ACTA PATHOL JPN 38: 883∼896, 1988.

Histological features predicting malignant transformation of nonmalignant hepatocellular nodules : A prospective study

BACKGROUND & AIMS Recent advances in imaging modalities allow the identification of borderline hepatocellular nodules that have the potential for malignant transformation. The aim of this study was to elucidate histological predictive features of borderline nodules by needle biopsy for the evolution to hepatocellular carcinoma (HCC). METHODS Thirty-four hepatocellular nodules diagnosed by needle biopsy were followed up for more than 6 months. Several histological parameters of these nodules that were related to malignant transformation were evaluated. RESULTS During the follow-up periods (median, 35 months), 5 of 34 nodules evolved to HCC during a follow-up of 6-15 months. Significant prognostic features of malignant transformation were an increased ratio of nuclear density of >1.5, clear cell change, small cell dysplasia, and fatty change of the hepatocytes. In multivariate analysis, an increased ratio of nuclear density of >1.5 and clear cell change were independent. CONCLUSIONS A nodule with an increased ratio of nuclear density, clear cell change, small cell dysplasia, and fatty change should be recognized to be a high risk for evolution to HCC. Particularly, the former two were independent prognostic factors for malignant transformation.

'Atypical adenomatous hyperplasia' in liver cirrhosis : low-grade hepatocellular carcinoma or borderline lesion?

Adenomatous hyperplasia, defined as a sizable parenchymal nodule in cirrhosis, was examined morphologically, Ninety‐seven nodules of adenomatous hyperplasia were ained from 47 cirrhotic livers and were divided into ‘ordinary’ (44 nodules) and ‘atypical’ (53 nodules) types. The former consisted of hepatocytes similar to those of the surrounding liver, and showed regularly distributed portal tracts. The latter type was composed of hepatocytes showing nuclear atypia, relative to the surrounding liver, and showed irregular or sparse portal tracts. Atypical nodules were histologically heterogen, possessing areas of normo‐trabecular, compact, pseudoglandular and/or scirrhous patterns. Several cytological changes, such as clear cell change, small or large cell change and fatty change, were intermingled variably within a given nodule. Atypical nodules showed expansive and/or replacing growth into the surrounding liver. Atypical hepatocytes also infiltrated into the fibrous septa and portal tracts. Foci of overt hepatocellular carcinoma were found in 11 of the 53 atypical nodules. These findings suggest that ordinary adenomatous hyperplasia may be a large‐sized regenerative nodule, while atypical adenomatous hyperplasia may be a hepatocellular neoplasm, a peculiar form of low‐grade hepatocellular carcinoma or borderline lesion, in which overt hepatocellular carcinoma is likely to evolve through multiple steps.

Extent of mediastinal node metastasis in clinical stage I non-small-cell lung cancer: The role of systematic nodal dissection

OBJECTIVE To determine the extent of lymph node metastasis in clinical stage I non-small-cell lung cancer (NSCLC). METHODS We performed a retrospective review of 524 patients with clinical stage I NSCLC who underwent lobectomy with systematic nodal dissection. RESULTS The nodal status was N0 in 409 patients (78%), N1 in 44 (8%), N2 in 67 (13%), and N3 in four (0.8%). Thirty-six patients had single-level mediastinal nodal metastases and 35 had multi-level metastases. The incidence of N2/3 disease in patients with adenocarcinoma/squamous cell carcinoma/other histologic types according to tumor size was 0/0/0%, respectively, in tumors < or = 10 mm in diameter, 12/0/0% in tumors 11-20 mm in diameter, 14/4/23% in tumors 21-30 mm in diameter, and 26/14/20% in tumors >30 mm in diameter. Nodal metastases to the upper mediastinum from middle or lower lobe lesions were frequently observed in 51 N2 adenocarcinomas, whereas those to the lower mediastinum from upper lobe lesions were rare. Of 10 N2 squamous cell carcinomas, seven had regional and three had non-regional nodal metastases. The 5-year survival rate was 68, 43, and 30% in N0, N1, and N2, respectively (P<0.01, N0 versus N1, N0 and N2). CONCLUSIONS Systematic mediastinal nodal dissection should be routinely performed for clinical stage I lung cancer to ensure the correct nodal status, but it might be dispensable in the patients with peripheral squamous cell carcinoma < or = 20 mm in diameter, with central squamous cell carcinoma < or = 30 mm, and with adenocarcinoma < or = 10 mm. When systematic nodal dissection cannot be performed, the incidence and extent of nodal metastases should be taken account with respect to histologic type, size, and location of the tumor.

Distant metastases in differentiated thyroid carcinomas: A clinical and pathologic study

Of 514 patients with differentiated thyroid carcinoma treated between 1970 and 1987, 34 (6.6%) had distant metastases. Twelve patients died of their distant metastases; eight of these patients died within 5 years from the time of initial diagnosis. Death from cancer was most frequent in the seventh decade. The metastases were most often found in the lungs and bones. In the fatal group, pleural, brain, and pericardial metastases were noted. Local recurrences were found only in 24% of these 34 patients. Histologic types of primary thyroid tumors and metastatic tumors were reexamined and classified using our criteria, which were mainly based on the World Health Organization nomenclature and currently obtained pathologic observations of thyroid tumors. In 31 thyroid tumors, the surgical specimens were available for review. Twenty-four tumors were papillary and seven were follicular. Of the 24 papillary carcinomas, nine were follicular, eight were well-differentiated, and seven were trabecular. On the other hand, the seven follicular carcinomas consisted of four well-differentiated, two solid, and one oxyphilic. The majority of the thyroid tumors showed an extrathyroidal extension; however, two were intrathyroidal carcinomas and two were encapsulated carcinomas, larger than 5 cm in diameter. Distant metastases were confirmed morphologically in 18 patients (11 by surgical or biopsy material, five by autopsy, and two by cytology). The histologic types of metastatic tumors were consistent with those of primary thyroid tumors. Diagnostic 131I uptake was examined in 32 patients and absorption of diagnostic 131I in metastatic tumors was demonstrated in 21 patients. The 10-year survival rate of patients with 131I accumulating metastases (70%) was significantly better than that of patients with metastases lacking such uptake (40%). Immunoreactivity for thyroglobulin in metastatic tumors was correlated with the 131I absorption. This finding indicated that immunostaining of thyroglobulin in metastatic tumors might be useful in the prediction of the effectiveness of 131I therapy.

Clinicopathologic study of alcohol-like liver disease in non-alcoholics; non-alcoholic steatohepatitis and fibrosis.

SummaryAlcohol-like liver injury (ALLI) in non-alcoholics has not been elucidated in Japan. The present study attempted to characterize the clinicopathologic features of ALLI in routine liver biopsies. ALLI was found in 1% of 561 biopsy cases obtained from 1988 to May, 1991 at Kanazawa University Hospital. Laboratory data characteristically showed only a mild to moderate degree of dysfunction, and none of the cases exhibited jaundice. Hepatic histology showed a mild to moderate degree of perivenular, pericellular and/or portal stellate fibrosis with a varying degree of fatty change and inflammatory cell infiltration. Portal stellate fibrosis with a varying degree of cell infiltration was more severe than the centrilobular or pericellular fibrosis in all cases. Intralobular inflammatory cell infiltration was associated with spotty or single hepatocyte necrosis, but extensive hepatocyte necrosis was not observed. Neutrophil infiltration was absent or minimal, and lymphocytes predominated in all cases. Mallory bodies were rare and were found in a few hepatocytes of only one of the 7 cases. The above histologic findings in ALLI were very similar to those seen in liver disease in Japanese alcoholics, and were somewhat different from ALLI reported in Western countries. In cases in which hepatic fibrosis, characterized by pericellular, perivenular or portal stellate fibrosis dominated without apparent hepatic necrosis and inflammation, the term “non-alcoholic steatofibrosis” is more suitable to depict its liver histology, being very similar to the alcoholic fibrosis frequently seen in Japanese alcoholics.

Angiomyolipoma predominantly composed of smooth muscle cells: problems in histological diagnosis

Five cases of angiomyolipoma (AML) composed exclusively or predominantly of smooth muscle cells (SMC) are presented to emphasize the histological diversity and to caution against errors in histological diagnosis.