Hisashi Otsuka

Occult papillary carcinoma of the thyroid: a study of 408 autopsy cases

On examination of the thyroid glands in 408 consecutive autopsy cases, 64 occult papillary carcinomas (OPC) were found in 46 cases (11.3%) whose age ranged from 16 to 82 years. Their incidence was 26 of 247 (10.5%) in male and 20/161 (12.4%) in female cases. No definite correlation was found between the incidence of carcinoma and sex or age. All 64 carcinomas were less than 7.7 mm in diameter. They exhibited nuclear characteristics of papillary carcinoma although their growth patterns were “follicular” in the tumors less than 1 mm, and “papillary” in 70% of the tumors more than 3 mm in diameter. The carcinomas were classified into three types according to the presence or absence of capsular formation and fibrosis: encapsulated tumors (ET), nonencapsulated sclerosing tumors (NEST), and nonsclerosing tumors (NST). The NEST (28 tumors) and NST (26 tumors) were found in persons of all ages, whereas ET (ten tumors) were found only in those of older than 53 years. The mean tumor diameters of the three types, 4.57 mm for ET, 2.10 mm for NEST, and 0.85 mm for NST, were significantly different. These findings suggested that papillary carcinomas arose as minute carcinomas showing follicular pattern at any age as NST and then changed to NEST and ET, and papillary pattern became prominent if the tumors continued to grow. Very minute carcinomas were detected in serial sections of two of 27 fibrosclerotic nodules. Occult papillary carcinomas were found at significantly high incidence in cases with adenomatous goiter.

Macroregenerative nodule of the liver. A clinicopathologic study of 345 autopsy cases of chronic liver disease

The livers of 345 autopsy cases of chronic liver disease were examined for macroregenerative nodule (MRN), a large nodular lesion more than 10 mm in diameter. A total of 86 lesions of MRN was found in 49 cases (14.2%): 32 were from 191 cases of hepatocellular carcinoma (HCC), 16 were from 148 cases of cirrhosis only, and one was from six cases of chronic hepatitis. The incidence (19.6%) and the size (12.1 mm) of MRN in macronodular type of cirrhosis were significantly higher and larger than those in other types of cirrhosis. Also, the average size of MRN lesions of cases with HCC (12 mm) was significantly larger than that of cases with cirrhosis only (10.5 mm). The incidence of liver cell dysplasia (LCD) in cases of MRN (67.3%) was significantly higher than that in cases without MRN (40.9%). The MRN lesions were divided into Type I and Type II, the latter having proliferative foci distinguishable from the surrounding tissue. Three of them contained atypical cells regarded as cancer. Type II lesions were larger in size, and cases with multiple MRN lesions were seen more frequently in cases of HCC. The average age of the patients with Type II lesion was 5 years older than those with Type I lesions. These findings suggest that MRN should not be ignored in the morphogenesis of HCC.

Nitro Compounds in Environmental Mixtures and Foods

Nitropyrenes (NPs) are the most potent mutagens that have been detected in environmental pollutants such as airborne particulates (Tokiwa et al., 1981b), car exhaust emissions (Lee et al., 1980; Gibson et al., 1981; Pederson and Siak, 1981; Schuetzle et al., 1981), photocopies (Lofroth et al., 1980; Rosenkranz et al., 1980), wastewater from gasoline stations (Ohnishi et al., 1983; Manabe et al., 1984), and used crankcase oil (Manabe et al., 1984). They are direct-acting mutagens in the Ames Salmonella mutation test; 1-NP, 1,3-diNP, 1,6-diNP, and 1,8-diNP produce 417; 65,500; 82,000; and 100,000 His+ revertants/plate/nmol, respectively, from strain TA98 in the absence of rat liver S9 mix (unpublished data). To induce mutagenicity the NPs are converted to the activated forms by nitroreductases in theSalmonella tester strain (TA98). Since strains TA98NR and TA98/1,8-DNP6 are defective in the specific activating enzymes, they show low mutagenicity by 1-NP and diNPs (Rosenkranz et al., 1981).

Liver cell dysplasia and hepatitis B surface antigen in liver cirrhosis and hepatocellular carcinoma

Liver tissues of 223 autopsy cases of cirrhosis and hepatocellular carcinoma were examined for liver cell dysplasia in relation to hepatitis B surface antigen (HBsAg) detected with orcein stain. Liver cell dysplasia was found in 94 cases (42.2%): 37 were from cases of cirrhosis only, and 53 were from cases of cirrhosis with hepatocellular carcinoma. There was a significant difference in the overall incidence of HBsAg in cases with and without dysplasia (70.2%:32.6%). A similar difference was found in all groups, i.e., those with cirrhosis, cirrhosis with hepatocellular carcinoma, and hepatocellular carcinoma only, in which none of 11 cases of HBsAg negative had dysplasia. A good correlation was seen between the semiquantitative grade of dysplasia and the incidence of HBsAg. These findings suggest a close relationship of HBsAg with liver cell dysplasia.

An immunohistochemical study of epithelial membrane antigen, cytokeratin, and vimentin in papillary thyroid carcinoma: Recognition of lethal and favorable prognostic types

Methods. Immunoreactivity for epithelial membrane antigen (EMA), cytokeratin, and vimentin was investigated in 15 papillary thyroid carcinomas (PTC) with distant metastases, 25 PTC without distant metastases, and 34 occult PTC without distant metastases that were found incidentally at autopsy.

Non-carcinogenicity of capsaicinoids in B6C3F1 mice

The carcinogenicity of a mixture of capsaicinoids (64.5% capsaicin and 32.6% dihydrocapsaicin) was examined in B6C3F1 mice. In a 13-week toxicity study, renal toxicity was observed in 1% capsaicinoid-treated males. Next, groups of 50 mice of each sex were given 0, 0.025, 0.083 or 0.25% capsaicinoids in powdered diet for 79 weeks and killed in week 83. Food intake was reduced in mice of all capsaicinoid-treated groups, especially females, because of the pungency of capsaicinoids, and inhibition of body weight gain was apparent in females. The numbers of tumour-bearing females in the high-dose groups were significantly lower than that in the controls, and the incidences of hepatocellular neoplasms in both sexes were negatively correlated with the dose of capsaicinoids (Cochran-Armitage trend test). Renal cell adenomas developed in one mouse each of 0.025 and 0.25% capsaicinoid-treated males. The incidences of other tumours were similar in the treated and control groups. Thus, the present study indicated that a mixture of capsaicinoids is not carcinogenic in B6C3F1 mice.

Hepatitis B antigen in the liver in hepatocellular carcinoma in Shikoku, Japan.

An analysis of 105 autopsy cases (77 male, 28 female) of hepatocellular carcinoma (HCC) showed that 90 cases (85.7%) were associated with liver cirrhosis, of which 75 cases (83.3%) were of the macronodular type. Hepatitis B surface antigen (HBsAg) was detected with orcein stain in the hepatic tissue in 58 cases (55.2%). The incidence of HBsAg in cases of HCC patients with cirrhosis (58.9%) was higher, but not significantly, than that in those without cirrhosis (33.3%). The mean age of HBsAg‐positive cases was five years less than that of HBsAg‐negative cases, the age distributions therefore being significantly different.

Subcutaneous pseudosarcomatous polyvinylpyrrolidone granuloma.

A 77-year-old man developed an induration of the buttock following repeated injections of an antihypertensive remedy containing polyvinylpyrrolidone (PVP). The excised tumor had a cellular, pseudosarcomatous appearance with abundant extracellular material, and resembled a myxoid liposarcoma. All of the staining reactions and infra-red spectrophotometry of the deposition indicated the presence of PVP. The awareness of such a cellular PVP granuloma is important for surgical pathologists so as to avoid the diagnosis of sarcoma.

Primary squamous cell carcinoma of the endometrium: a case report and a suggestion of new histogenesis

A case of primary endometrial squamous cell carcinoma (ESCC) in a 75-year-old woman is reported. In her endometrium, mature stratified squamous epithelium was associated with mucinous glands in which epithelium and glands were identical to those of the uterine cervix, but which were not connected with the cervix. Thus, the endometrial squamous epithelium with mucinous glands was diagnosed as heterotopic cervical tissue. This heterotopia was surrounded by ESCC and connected with it. The present case suggests that some ESCCs may arise in heterotopic cervical epithelium in the endometrium.

Histopathological and Immunohistochemical Studies on Nickel Sulfide‐induced Tumors in F344 Rats

Twenty‐five tumors induced in F344 male rats were examined histologically and immunohistochemically using antibodies against myoglobin, myosin, desmin and cathepsin B. Eight were from rats which had been given intramuscular (im) injection and 17 were from rats which had been given subcutaneous (sc) injection of 5 mg of Ni3S2. Among 10 rhabdomyosarcomas, myoglobin was detectable in 3, myosin in 8, and desmin in all, but cathepsin B was present in none. Out of 8 malignant fibrous histiocytomas, cathepsin B was detectable in all, but the other antigens were absent. In a leiomyosarcoma, only desmin was detected. In two fibrosarcomas, none of the markers were detected. In four undetermined tumors, one reacted only with anti‐desmin antibody, two with only anti‐cathepsin B antibody, and one with none of the antibodies. Of the three myogenic markers utilized in this study, anti‐desmin antibody appeared to be the most sensitive. Cathepsin B was found mainly in the histiocytic cells of malignant fibrous histiocytoma. Thus, desmin appears to be particularly valuable in distinguishing immature myogenic tumors from other primitive tumors, while cathepsin B is useful in distinguishing malignant fibrous histiocytoma from other plemorphic mesenchymal tumors.