Carcinosarcoma of the parotid gland: an unusual case with large-cell neuroendocrine carcinoma and rhabdomyosarcoma.

We report a case of carcinosarcoma of the parotid gland in a 72-year-old Japanese man. The patient noticed a rapidly enlarging hard mass in the right parotid gland. He underwent radical parotidectomy with cervical lymph node dissection. The resected tumor measured 3.5 x 4.5 cm and histopathologically showed carcinomatous and sarcomatous components. The carcinomatous component consisted of large-cell neuroendocrine carcinoma (LCNEC), squamous cell carcinoma and adenocarcinoma not otherwise specified, while the sarcomatous component included spindle cell sarcoma not otherwise specified, so-called myxosarcoma and rhabdomyosarcoma. The LCNEC component was predominant within the whole tumor. The diagnoses of LCNEC and rhabdomyosarcoma were also confirmed immunohistochemically. With regard to histopathogenesis, based on the lack of histopathological evidence and antecedent history of pleomorphic adenoma, we considered the present case to be de novo, not expleomorphic adenoma.

Expression of beta-catenin, E-cadherin and cyclin D1 in adenoid cystic carcinoma of the salivary gland.

We evaluated the expression of beta-catenin, E-cadherin, and cyclin-D1 in 23 cases of adenoid cystic carcinoma (ACC) of the salivary gland. We detected beta-catenin on the cell membranes in all ACCs, but its distribution was irregular, as compared to that on normal structures. In three out of the 23 cases, beta-catenin was detected in the nuclei, as well as on cell membranes. Polymerase chain reaction (PCR) and direct sequencing revealed a missense mutation in one case in which beta-catenin had been detected in the nuclei of tumor cells. We also detected E-cadherin on cell membranes with a similar irregular distribution to that of beta-catenin. In 11 cases (almost 48%) of ACC, cyclin D1 was localized in cell nuclei but there was no correlation with the nuclear staining of the beta-catenin. Our results suggest that disturbances in the distribution of beta-catenin and E-cadherin might affect the morphology ofACC and that a small fraction of cases of ACC are characterized by a mutation in the beta-catenin gene, which is associated with the nuclear accumulation of the product of this gene but does not affect the transcription of the gene for cyclin-D1.

Mild hypothermia reduces expression of intercellular adhesion molecule-1 (ICAM-1) and the accumulation of neutrophils after acid-induced lung injury in the rat.

BACKGROUND: The pathophysiology of the acute phase of acid-induced lung injury (AILI) has been elucidated. However, once acute respiratory distress syndrome (ARDS) develops, the mortality rate remains high and there is, as yet, no effective therapy. There are reports that application of mild hypothermia is an effective treatment for ARDS. In this study, we hypothesize that mild hypothermia inhibits activation of neutrophils and expression of intercellular adhesion molecule-1 (ICAM-1) in an injured lung. We studied the effects of mild hypothermia on the expression of ICAM-1 and the accumulation of neutrophils after AILI in the rat. METHODS: Male Sprague-Dawley rats were randomly allocated to one of the four groups: control normothermic group, induced mild hypothermia group, acid-instilled normothermic group, and acid-instilled group with mild hypothermia. At 6 h after instillation of acid, lungs were removed to measure neutrophil activity and to detect the expression of ICAM-1 in each group. RESULTS: Oxygenation in acid-instilled rats was significantly impaired as compared to that in non-instilled groups, but induction of mild hypothermia gradually improved oxygenation. Expression of ICAM-1 was enhanced in the acid-instilled normothermic group. By contrast, no overexpression of ICAM-1 and its mRNA was detected in the acid-instilled hypothermic group. In addition, accumulation of neutrophils was markedly inhibited after exposure to mild hypothermia irrespective of the instillation of acid. CONCLUSION: Our data suggest mild hypothermia can inhibit the adhesion, activation, and accumulation of neutrophils during the acute phase of AILI in the rat and may have the potential to reduce ongoing inflammation of ALI or ARDS.

Zoonotic onchocerciasis caused by a parasite from wild boar in Oita, Japan. A comprehensive analysis of morphological characteristics of the worms for its diagnosis.

Histological examination of a nodule removed from the back of the hand of a 58-year-old woman from Oita, Kyushu, Japan showed an Onchocerca female sectioned through the posterior region of the worm (ovaries identifiable) and young (thin cuticle). Six Onchocerca species are enzootic in that area: O. gutturosa and O. lienalis in cattle, O. suzukii in serows (Capricornis crispus), O. skrjabini and an Onchocerca sp. in Cervus nippon nippon, and O. dewittei japonica in wild boar (Sus scrofa leucomystax). Diagnostic characters of female Onchocerca species, such as the cuticle and its ridges, change along the body length. Tables of the histologic morphology of the mid- and posterior body-regions of the local species are presented. In addition, it was observed that transverse ridges arose and thickened during the adult stage (examination of fourth stage and juvenile females of O. volvulus). The specimen described in this report, with its prominent and widely spaced ridges, was identified as O. d. japonica. Four of the 10 zoonotic cases of onchocerciasis reported worldwide were from Oita, three of them being caused by O. d. japonica, the prevalence of which in local wild boar was 22 of 24 (92%).

The expression of PDGF, its receptors and capillary morphometry in the developing lung: quantitative studies.

The aim of the present study was the evaluation of the expression levels of PDGF-A and B, and PDGFR-alpha, andchanges of capillary cross-sectional areas during terminal vascular network formation in the developing lung. Pathogen-free fetuses and newborns used for rats were used. Lungs were processed for frozen section immunohistochemical staining and parallel tissue specimens were prepared for transmission electron microscopy. The expression levels of PDGF-A and B, and PDGFR-alpha were obtained using quantitative image analysis. Additionally. the morphometry of capillary cross-sectional area was performed. We found that the expression levels of the studied antigens fluctuated, and the highest values were found in21-day old fetuses (p < 0.0001). Although there were no significant differences of the area of "a single" capillary, the area of the endothelium decreased significantly in perinatal period (p <0.0001). We conclude that the statistically significant changes of the studied antigens' expression as well as the of capillary cross-sectional area occur in the perinatal period,

Preferential transcription of a gene for alpha amylase in the carcinoid tumor of African rodent Mastomys natalensis.

The carcinoid tumor in Mastomys natalensis provides a useful animal model of tumorigenesis. We investigated preferentially transcribed genes in this carcinoid tumor by differential hybridization. Fourteen clones corresponding to high levels of transcription were isolated from a cDNA library. Sequencing analysis and a homology search revealed that the clones corresponded to genes for chromogranin and alpha-amylase. High-level transcription of a gene for alpha-amylase gene in Mastomys carcinoid tumor was confirmed by Northern blotting analysis. Furthermore, Western blotting analysis confirmed the expression of alpha-amylase in tumors at the protein level. Immunohistochemical staining revealed alpha-amylase in the cytoplasm of Mastomys carcinoid tumors. Our results demonstrated that an exocrine enzyme 'amylase' could be produced ectopically by a neuroen docrine tumor.

Expression of vascular endothelial growth factor and its receptors in the developing rat lung.

We examined the regulation of the expression of vascular endothelial growth factor (VEGF) and its specific receptors, fetal liver kinase receptor (Flk-1), and fms-like tyrosine kinase receptor (Flt-1) during formation of the capillary network in the developing rat lung. An immunohistochemical study of lung tissue from 19- and 21-d-old fetuses and 1-, 3-, 5-, 7-, and 14-d-old animals revealed that the level of expression of both VEGF and Flk-1 is significantly higher before birth (p < 0.0001) than after. Increased expression of Flt-1 on the first day after birth (p < 0.0001) suggests that this receptor might play an important role in capillary growth in the perinatal period. Immunostaining also revealed the colocalization of VEGF, Flt-1, and Flk-1 in endothelial cells of the lung capillaries at the ultrastructural level. The present studies revealed that VEGF and its two receptors are upregulated during the development of capillaries in the fetal and newborn rat lung.

Epithelial-myoepithelial carcinoma harboring p53 mutation.

A case of epithelial-myoepithelial carcinoma of the parotid gland harboring p53 mutation is reported. The tumor removed from a 67-year-old Japanese female was composed of an organoid biphasic population of cells: inner dark epithelial cells were surrounded by clear myoepithelial cells. The cells were immunopositive for EMA and smooth muscle actin, respectively. Some of the epithelial cells formed solid nests. Immunostaining for proliferating cell nuclear antigen (PCNA) resulted in a higher percentage of labeled cells in the solid epithelial region than in the region with the more general biphasic pattern. Genetic analysis, including polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and nucleotide sequencing, revealed a mutation in codon 207 (aspartic acid to glycine) of the p53 tumor-suppressor gene. To our knowledge, this is the first report of a mutation in the p53 gene in an epithelial-myoepithelial carcinoma of the salivary gland.

Quantitative immunohistochemical analysis of the expression of CD31 during lung development in the rat.

The CD31 antigen, known also as the platelet/endothelial cell adhesion molecule 1, has been shown to be a good marker for monitoring the formation of the vasculature in mammals. Available evidence suggests that the expression of CD31 is regulated during embryonal and fetal development. The aim of the present study was to evaluate the changes in the expression of CD31 during the development of the rat lung. We studied samples of lung tissue from rat fetuses (17, 19 and 21 days after conception), newborns (1, 3, 5, 7, 14 and 21 days after birth) and adult animals. The tissue samples from rats in the various age groups were divided into sets, with all age groups being represented in every set. After immunohistochemical localization of the antigen, the amount of chromogen deposited after the immunoreaction (defined in terms of optical density; OD) was evaluated by image analysis in the various sets. Measurements were obtained twice from each set, and the results were reproducible (paired t test, alpha = 0.05). We subjected the results of measurements from all sets to an analysis of variance (ANOVA). The amount of chromogen (OD) decreased from fetal day 19 to 5 days after delivery and then increased again. The decrease in the level of expression of CD31 on days 3 and 5 after delivery was significant (p < 0.0001).

Myxoid adrenal cortical adenoma.

Myxoid adrenal cortical adenoma is a rare tumor and, to our knowledge, only 16 cases have been reported. We present the case of a 56-year-old Japanese man who was admitted to hospital because of a right adrenal mass that was discovered during a routine physical examination. The resected mass was well circumscribed and contained canary yellow multinodular regions that were surrounded by a brown gelatinous region. Histologically, the multinodular regions resembled a conventional adrenal cortical adenoma, being composed of solid aggregates of large clear or eosinophilic cells. In the gelatinous region, anastomosing small eosinophilic or vesicular cells were visible within a myxoid stroma that contained large amounts of acidic mucopolysaccharides. Light-microscopic findings were consistent with a diagnosis of adenoma. Immunohistochemical staining revealed that a small number of tumor cells were positive for vimentin, and the MIB-1 labeling index was less than 1%. Flow cytometry demonstrated that cells were diploid. At the ultrastructural level, many fat droplets were found in the large clear cells in the multinodular regions. Small eosinophilic cells in the myxoid region contained many mitochondria but few fat droplets. There were no findings suggestive of malignancy. Although the adrenal cortex might have the potential to produce connective tissue-type mucin as a consequence of its mesodermal origin, the mechanism of production of acidic mucopolysaccharides in a myxoid adrenal cortical tumor remains to be clarified.

Immunohistochemical study of the distribution of endogenous biotin and biotin-binding enzymes in ductal structures of salivary gland tumours.

To clarify the pathologic value of endogenous biotin in the salivary gland, we examined in a series of neoplasms of the salivary gland by immunohistochemical staining the distribution of endogenous biotin and of biotin-binding enzymes, namely, acetyl CoA carboxylase (AC), which is a cytosolic enzyme, and pyruvate carboxylase (PC), which is a mitochondrial enzyme. In pleomorphic adenoma, we found biotin and PC in ductal epithelial elements, while AC was found mainly in myoepithelial elements. Carcinoma ex pleomorphic adenoma, adenocarcinoma and mucoepidermoid carcinoma were frequently immunopositive for biotin, PC and AC, while adenoid cystic carcinoma was rarely immunopositive for biotin, PC or AC. These results indicate that endogenous biotin might be associated with the mitochondrial enzyme, which is present at high levels in ductal cells of the salivary gland. However, the neoplastic cells in adenoid cystic carcinoma seemed to have an unusual expression of biotin and related enzymes.

Ultrastructural and morphometric studies related to expression of the cell adhesion molecule PECAM-1/CD31 in developing rat lung.

It has recently been postulated that platelet/endothelial cell adhesion molecule-1 (PECAM-1/CD31) might play a role in vascular tube formation. To evaluate the role of PECAM-1/CD31 in the formation of the capillary network in vivo, we conducted an ultrastructural immunohistochemical evaluation of the localization of PECAM-1/CD31 and its developmentally regulated expression in the periphery of the lungs of fetal, newborn, and adult rats. PECAM-1/CD31 was present mainly on luminal surfaces and at the junctions between endothelial cells. Moreover, in fetal lung, products of the immunoreaction were also found on the abluminal surfaces of endothelial cells. To relate those findings to the developmental changes in the capillary area of the lung, we performed a morphometric study of electronmicrographs. The cross-sectional area of blood vessels at the periphery of the lungs was significantly greater in 15-19-day-old fetuses than in postpartum animals (p<0.0001). Disappearance of the expression of PECAM-1/CD31 on the abluminal endothelial surface paralleled the changes in the cross-sectional area of blood vessels that occurred during the perinatal period. (J Histochem Cytochem 48:1283-1289, 2000)

Clonal analysis of the epithelial component of Warthin's tumor.

The proliferation of the epithelial component of Warthin's tumor is generally considered to represent a neoplastic condition. There has been much controversy about the histogenesis of this tumor, and the clonality of the epithelial component has not been clarified. We examined the clonal status of epithelial cells of Warthin's tumor by using a polymerase chain reaction (PCR) method based on trinucleotide repeat polymorphism of the X chromosome-linked human androgen receptor gene (HUMARA) and on random inactivation of the gene by methylation. Total DNA was isolated from formalin-fixed, paraffin-embedded tissue from 16 women with Warthin's tumor. Of the 16 cases analyzed, 7 were heterozygous for the HUMARA polymorphism and informative. The epithelial components of the tumors from the 7 cases were microdissected under the light microscope, and were subjected to extraction of DNA and HUMARA analysis. Using a permanent aqueous mounting medium during microdissection, we succeeded in reducing the rate of contamination by lymphocytes in the samples to less than 10%. All 7 cases showed patterns of polyclonal proliferation in the HUMARA analysis. Our results showed the nonclonal nature of Warthin's tumor, suggesting that Warthin's tumor is a non-neoplastic tumor-like condition. HUM PATHOL 31:1377-1380.

Clinicopathological and immunohistochemical study of cancer arising from Barrett's esophagus.

In Japan, Barrett's esophageal cancer is a very rare disease. We examined clinicopathologically and immunohistologically 4 patients with Barrett's esophageal cancer who underwent surgical resection in our department. Barrett's esophageal mucosa was classified into 3 types for detailed observation. Specialized columnar epithelium (SCE) remained on the orifice side of carcinoma, and progression to adenocarcinoma was observed in some dysplastic glands. positive findings were detected on p53 immunohistochemical staining, and the ki-67 labeling index was higher than other types. SCE-type Barrett's esophagus may be a precancerous lesion arising prior to the development of adenocarcinoma.

Mutations of p53 in thyroid carcinoma with an insular component.

Thyroid carcinoma with an insular component (TCIC) is considered noteworthy in view of its peculiar histopathological features and clinicopathological behavior. The purpose of the present study was to clarify the rate of mutation in the p53 gene in TCIC as compared with rates in papillary and follicular carcinomas of the thyroid. Formalin-fixed and paraffin-embedded blocks of tissue from 46 cases of TCIC were analyzed. DNA was extracted from tissues and exons 5 through 8 of the p53 gene were amplified by the polymerase chain reaction. Mutations were detected by analysis of single-strand conformation polymorphism. Of the 46 cases of TCIC, 6 had a mutation in exon 5, 2 in exon 7, and 5 in exon 8, while 1 case had mutations in all exons examined. The mutation rate of the p53 gene in TCIC was 38%. Immunostaining revealed overexpression of p53 in nuclei that were mainly in areas of the insular component rather than in surrounding areas of well-differentiated carcinoma. The frequency of positive immunostaining in TCIC was 53%. Considering that TCIC is intermediate between papillary plus follicular carcinoma and anaplastic carcinoma in terms of survival and the rate of mutation of the p53 gene, we can speculate that mutation in the p53 gene might be associated with the insular component and might play an important role in the clinicopathological behavior of thyroid carcinoma.

Expression of splice variants of CD44 in thyroid neoplasms derived from follicular cells.

Isoform expression of CD44 in follicular carcinoma (FC) of the thyroid was analyzed by immunohistochemical staining and compared to the isoforms in follicular adenoma (FA) and papillary carcinoma (PC) of the thyroid. Variant isoforms of CD44 (CD44v) were detected in these neoplastic cells but not in non-neoplastic cells. CD44v6 was expressed in PC with nodal metastasis and also in FC at significantly higher frequencies than those in PC without metastasis and FA. The frequency of expression of CD44v3 was significantly higher in PC with nodal metastasis than in PC without metastasis. The reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blotting analysis revealed the presence of a transcript for a variant of CD44 that contained variant exon 6 in FA, FC and PC. DNA sequencing of the products of RT-PCR yielded three species of cDNA for CD44v. One of the cDNA corresponded to a transcript that contained variant exon 6. These results suggest that immunohistochemical staining and RT-PCR with Southern blotting analysis for CD44v6 might be a useful diagnostic tool for the differentiation of FC from FA and that the expression of CD44v3 and CD44v6 might be important for the development of nodal metastasis in cases of PC.

Chronic thyroiditis as a favorable prognostic factor in papillary thyroid carcinoma.

A subgroup of patients with papillary thyroid carcinoma (PTC) also has chronic thyroiditis (CT) as an associated disease of the thyroid. To assess the prognostic value of CT in patients with PTC, we reviewed the histological slides of 2225 patients with PTC who had undergone surgery between 1971 and 1992. Of the 2225 patients, 692 were excluded from the analysis because regional lymph nodes and/or nonneoplastic thyroid tissues were unavailable for histological assessment. The series included 281 patients with CT in nonneoplastic thyroid tissue and 1252 without CT. We performed statistical analyzes by the log-rank test and Cox's proportional-hazard method. Sixty-two (5.0%) of the 1252 patients without CT died of metastatic disease during the follow-up period and the relapse-free 10-year survival rate was 85%. By contrast, only 2 (<1.0%) of the 281 patients with CT died, and their relapse-free 10-year survival rate was 95%. The difference between patients with CT and those without CT in terms of relapse-free and overall survival was statistically significant (p < 0.0001). Risk factors for unfavorable outcome were age 45 years or more, absence of psammoma bodies, and absence of CT (p < 0.0001), followed by vascular invasion (p = 0.0007), male sex (p = 0.0013), and metastasis to regional lymph nodes (p = 0.047). Multivariate analysis indicated that all of these factors with the exception of gender were independent factors in the final model for overall survival. Chronic thyroiditis in the nonneoplastic thyroid of patients with PTC is a powerful prognostic factor for both relapse-free and overall survival.

A ciliated cyst as a component of pleomorphic adenoma of the parotid gland.

A large cyst, lined with ciliated cells (ciliated cyst), was found as a component of a pleomorphic adenoma of the left parotid gland in a 34-year-old Japanese man. The dimensions of the tumor were 25 x 33 mm and it consisted of a solid mass with a centrally located cyst 20 x 23 mm, which contained yellowish-brown material of muddy consistency. The tumor was encapsulated and the solid mass had features typical of a pleomorphic adenoma. The inner surface of the cyst was lined with ciliated cells and scattered mucus-secreting cells in addition to cuboidal-to-flattened cells. In some regions, the neoplastic cells of the pleomorphic adenoma were exposed to the cavity of the cyst. A histological transformation from ciliated cells to pleomorphic adenomatous cells was also observed. These findings indicated that the ciliated epithelium was an element of the tumor. This is the first report, to our knowledge, of a ciliated cyst derived from some elements of a pleomorphic adenoma of the salivary gland.

Effects of acidic and basic fibroblast growth factors on cell proliferation in pleomorphic adenoma of the parotid gland.

Localization and biochemical characteristics of acidic and basic fibroblast growth factor (aFGF and bFGF) were studied in the normal parotid gland (NPG) and in pleomorphic adenoma (PA). In addition, the effects of these factors on proliferation activity were investigated in cultured PA cells. aFGF and bFGF were detected immunohistochemically in 62% and 58% of NPG and 44% and 58% of PA, respectively, and they localized in the cytoplasm of the ductal segments of the NPG, and of the tubular, trabecular and squamous components of PA. Both aFGF and bFGF, each with a molecular weight of 18 kDa, were identified in PA using heparin-sepharose chromatography and Western blot analysis. Both recombinant human aFGF and bFGF stimulated [3H]-thymidine incorporation by cultured PA cells. These results indicated that aFGF and bFGF, probably produced by neoplastic cells, play important roles in the proliferation of PA of the parotid gland.

Rhabdomyosarcoma of the urachus. A case report.

BACKGROUND: Rhabdomyosarcoma of the urachus is extremely rare, and only two cases have been reported. Cytologic, histologic, immunochemical and electron microscopic findings in embryonal rhabdomyosarcoma of the urachus are presented. CASE: Embryonal rhabdomyosarcoma of the urachus developed in a 2-year-old boy. Imprint smears prepared prior to a histologic examination for a rapid report contained many malignant cells isolated or in clusters in a myxoid background. They were uniformly small, with round to oval nuclei and scant cytoplasm, and immunohistochemically positive for desmin and alpha-sarcomeric muscle actin but negative for myoglobin. This tumor was diagnosed cytologically as embryonal rhabdomyosarcoma because of its skeletal muscle origin and because of its similarity to one of the so-called small round cell tumors of childhood. Histologic examination confirmed the cytologic diagnosis. CONCLUSION: Cytologic, histologic and electron microscopic findings were identical to those described previously for embryonal rhabdomyosarcoma at other sites. In immunochemical examinations, cytologic samples fixed in ethanol are more useful than histologic ones fixed in formalin. Then, in order to differentiate poorly differentiated rhabdomyosarcoma from other small round cell tumors in children, desmin and alpha-sarcomeric actin, rather than myoglobin, are recommended.