Anatomic properties of myocardial bridge predisposing to myocardial infarction.

BACKGROUND: A myocardial bridge (MB) that partially covers the course of the left anterior descending coronary artery (LAD) sometimes causes myocardial ischemia, primarily because of hemodynamic deterioration, but without atherosclerosis. However, the mechanism of occurrence of myocardial infarction (MI) as a result of an MB in patients with spontaneously developing atherosclerosis is unclear. METHODS AND RESULTS: One hundred consecutive autopsied MI hearts either with MBs [MI(+)MB(+) group; n=46] or without MBs (n=54) were obtained, as were 200 normal hearts, 100 with MBs [MI(-)MB(+) group] and 100 without MBs. By microscopy on LADs that were consecutively cross-sectioned at 5-mm intervals, the extent and distribution of LAD atherosclerosis were investigated histomorphometrically in conjunction with the anatomic properties of the MB, such as its thickness, length, and location and the MB muscle index (MB thickness multiplied by MB length), according to MI and MB status. In the MI(+)MB(+) group, the MB showed a significantly greater thickness and greater MB muscle index (P<0.05) than in the MI(-)MB(+) group. The intima-media ratio (intimal area/medial area) within 1.0 cm of the left coronary ostium was also greater (P<0.05) in the MI(+)MB(+) group than in the other groups. In addition, in the MI(+)MB(+) group, the location of the segment that exhibited the greatest intima-media ratio in the LAD proximal to the MB correlated significantly (P<0.001) with the location of the MB entrance, and furthermore, atherosclerosis progression in the LAD proximal to the MB was largest at 2.0 cm from the MB entrance. CONCLUSIONS: In the proximal LAD with an MB, MB muscle index is associated with a shift of coronary disease more proximally, an effect that may increase the risk of MI.

Intraductal tubulopapillary neoplasms of the pancreas distinct from pancreatic intraepithelial neoplasia and intraductal papillary mucinous neoplasms.

We have encountered cases of unusual intraductal pancreatic neoplasms with predominant tubulopapillary growth. We collected data on 10 similar cases of "intraductal tubulopapillary neoplasms (ITPNs)" and analyzed their clinicopathologic and molecular features. Tumor specimens were obtained from 5 men and 5 women with a mean age of 58 years. ITPNs were solid and nodular tumors obstructing dilated pancreatic ducts and did not contain any visible mucin. The tumor cells formed tubulopapillae and contained little cytoplasmic mucin. The tumors exhibited uniform high-grade atypia. Necrotic foci were frequently observed, and invasion was observed in some cases. The ITPNs were immunohistochemically positive for cytokeratin 7 and/or cytokeratin 19 and negative for trypsin, MUC2, MUC5AC, and fascin. Molecular studies revealed abnormal expressions of TP53 and SMAD4 in 1 case, but aberrant expression of beta-catenin was not observed. No mutations in KRAS and BRAF were observed in the 8 cases that were examined. Eight patients are alive without recurrence, 1 patient died of liver metastases, and 1 patient is alive but had a recurrence and underwent additional pancreatectomy. The mitotic count and Ki-67 labeling index were significantly associated with invasion. All the features of ITPN were distinct from those of other known intraductal pancreatic neoplasms, including pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and the intraductal variant of acinar cell carcinoma. Intraductal tubular carcinomas showed several features that were similar to those of ITPN, except for the tubulopapillary growth pattern. In conclusion, ITPNs can be considered to represent a new disease entity encompassing intraductal tubular carcinoma as a morphologic variant.

p53 is an indicator of tumor progression in early but not advanced gastric carcinomas.

BACKGROUND/AIMS: p53 plays an important role in the development of gastric carcinomas through its effect on apoptosis. Its use as a biomarker of tumorigenesis and progression in clinical tissue is currently under consideration. This project assessed its value in early and advanced stage gastric carcinomas. METHODOLOGY: The characteristics of positive staining for p53 was evaluated in 202 gastric adenocarcinomas classified into early stage (T1) (127 cases) and advanced stage (T2, 3 and 4) (75 cases) using the tumor-node-metastasis classification. Four subgroups (classified as p53 negative, +, ++ and +++ according to the level of positivity) were investigated for relationships with apoptosis (morphology) or cell proliferation (Ki-67). RESULTS: The mucosa of early stage and both mucosa and subserosa of advanced cancers were examined. p53-positive early stage cancers had more apoptosis but also more proliferation than p53-negatives (P<0.05), perhaps indicating conferral of a growth advantage. In advanced cancers, there was no correlation between apoptosis and extent of p53 positivity. p53 positivity had no correlation with cell proliferation in the mucosa and subserosa of these cancers. CONCLUSIONS: p53 may be useful as an indicator of development and progression in early stage gastric cancers but this is not the case for advanced stage gastric cancers.

Immunohistochemical and ultrastructural investigation on cutaneous neuroendocrine carcinoma: report of a case and review of the literature.

We report a tumor in an 80-year-old man that was difficult to distinguish from other tumors, i.e., small cell carcinoma of the lung, PNET/Ewing tumor, malignant lymphoma, or malignant melanoma (amelanotic), and which was finally identified as cutaneous neuroendocrine carcinoma using immunohistochemical and ultrastructural methods. Autopsy did not show any tumors in the lungs, excluding the possibility of small cell carcinoma of the lung. Immunohistochemistry tests gave negative results for LCA, UCHL-1, CD3, and CD20, thereby excluding malignant lymphoma, and the negative results for S-100 protein and HMB-45 ruled out malignant melanoma. The possibility of PNET/Ewing sarcoma was also excluded because of negativity for CD99. In addition, the ultramicrostructure showed intercellular junctional complexes and neuroendocrine granules, indicating that the tumor had characteristics of both epithelial and neuroendocrine tissues. We therefore diagnosed the primary carcinoma of the skin as cutaneous neuroendocrine carcinoma.

Locally recurrent central-type early stage lung cancer < 1.0 cm in diameter after complete remission by photodynamic therapy.

BACKGROUND: It is well known that central-type early stage lung cancer < 1.0 cm in diameter shows almost 100% complete response (CR) to photodynamic therapy (PDT). However, we have encountered cases of local recurrence after CR of tumors with a surface diameter < 1.0 cm. PATIENTS AND METHODS: Ninety-three patients with 114 lesions were followed up, and cases of recurrence after CR has been obtained with initial tumors that had a diameter < 1.0 cm were examined. We compared the cytologic findings of local recurrence after CR to the cytologic findings before PDT. The relationship between the cell features and the depth of bronchial tumor invasion before PDT and on recurrence was evaluated. RESULTS: The CR and 5-year survival rates of patients with lesions < 1.0 cm were 92.8% (77 of 83 patients) and 57.9%, respectively; meanwhile, in the group of patients with lesions > or = 1.0 cm, CR and 5-year survival rates were 58.1% (18 of 31 patients) and 59.3%. There was a significant difference in efficacy between the two groups (p < 0.001). Recurrences after CR were recognized in 9 of 77 lesions (11.7%) < 1.0 cm. When the recurrent tumor cells showed type I-II (low-to-moderate atypia) at the same site initially treated, CR could be obtained by a second PDT. Type III cells (high-grade atypia) showed the characteristics of tumor cells from deeper layers of the bronchial wall. Local recurrence at the same site may be caused by residual tumor cells from deep layers because of inadequate laser irradiation and penetration. CONCLUSIONS: To reduce the recurrence rate, it is essential to accurately grasp the tumor extent and the depth of the bronchogenic carcinoma before performing PDT. Analysis of cell features of recurrent lesions after CR appears to be a useful source of information as to the depth of cancer invasion in the bronchial wall.

Frequent loss of E-cadherin and/or catenins in intrabronchial lesions during carcinogenesis of the bronchial epithelium.

Inactivation of the cadherin-mediated cell-cell adhesion system is believed to play a role in the initial steps of cancer invasion and metastasis. Expression of E-cadherin and its intracytoplasmic binding molecules (alpha-catenin, beta-catenin, and plakoglobin) was examined immunohistochemically in 84 cases of intrabronchial precancerous lesions (bronchial squamous metaplasia (BSM) without atypia, BSM with atypia, dysplasia), and 21 cases of carcinoma in situ, and 4 cases of microinvasion to the bronchial wall, and 32 cases of stage I well differentiated squamous cell carcinoma (squamous cell carcinoma) to investigate the association between expression of E-cadherin and/or catenins and cancer progression. Reduced expression of E-cadherin and/or catenins was closely correlated with an atypical grade of dysplasia in the basal layer (p<0.05). In particular, downregulation of E-cadherin and/or catenins was associated with an atypical grade of BSM with atypia in intrabronchial lesions (p<0.01). We conclude that downregulation of alpha-catenin and/or beta-catenin, which may reflect dysfunction of the cadherin-mediated cell-cell adhesion system, is an important marker for atypical grade during carcinogenesis of the bronchial epithelium.

Cytological characteristics of pulmonary large cell neuroendocrine carcinoma.

To establish cytological features of pulmonary large cell neuroendocrine carcinoma (LCNEC), we evaluated the cytological characteristics of LCNEC. Samples from 25 histologically confirmed LCNECs (14 touch imprint (TI) and 11 curettage) were analyzed. The findings were compared with those for seven small cell lung carcinomas. Cytological findings of TIs were as follows: Tumor cells were medium- to large-sized, round or polygonal, and nuclear polymorphism was observed. Some of the tumor cells had clearly identified cytoplasms, but naked nuclei were frequently observed. Nuclei were round, oval, or polygonal, and possessed thin and smooth nuclear membranes. The nuclear chromatin pattern was finely or coarsely granular. One or two nucleoli were observed in the nuclei, but were inconspicuous in some cases. Tumor cells appeared in clusters, and rosette formation was observed, but single cells were frequently observed also. Necrotic background and nuclear streaking were frequently observed. In brush or curettage specimens, the number of cells observed on a glass was small, but the findings were almost the same as those for the TI samples. TI samples have characteristic features, such as a neuroendocrine morphologic pattern, large cell size, abundant cytoplasm, finely or coarsely granular chromatin of the nucleus, and prominent nucleoli, and the diagnosis of LCNEC is possible. In brush or curettage specimen, the LCNEC diagnosis may be possible if a sufficient number of tumor cells are obtained.

Histopathological evaluation of fluorescence bronchoscopy using resected lungs in cases of lung cancer.

Objective evaluation of the performance of autofluorescence bronchoscopy based on analysis of thin sections of the bronchus of resected lungs was performed and compared with the results of preoperative autofluorescence bronchoscopy. Conventional bronchoscopy and autofluorescence bronchoscopy were performed prior to surgery for lung cancer. Thin sections of the bronchus were obtained from the resected specimens. The thin sections were pathologically analyzed and the diagnostic accuracy of endoscopy was calculated. The subjects were 30 consecutive operable lung cancer cases who received white light and autofluorescence bronchoscopy before operation. A total of 163 thin sections of the bronchi in the resected lungs were made. The sensitivity of white light bronchoscopy for cancer was 90 and 31% for dysplasia. The respective figures for autofluorescence bronchoscopy were 97 and 50% for cancer and dysplasia. The specificity of white light and autofluorescence was 88 and 84%, respectively. The diagnostic accuracy of autofluorescence bronchoscopy was objectively confirmed. Autofluorescence examination showed better sensitivity for cancerous/precancerous lesions and the evaluation of the extent of cancer invasion was accurate.

Usefulness of TA02 (napsin A) to distinguish primary lung adenocarcinoma from metastatic lung adenocarcinoma.

TA02 (napsin A) associated with primary lung adenocarcinoma detected by the two-dimensional polyacrylamide gel electrophoresis (2-DE), has a molecular weight of 35.0 kDa and an isoelectric point 5.29. We developed a mouse monoclonal antibody against the N-terminal of the TA02 molecule (clone TMU-Ad02 (6A1)) and attempted to investigate its immunohistochemical reactivity for nodular lesions of the peripheral lung, and evaluate its usefulness for making a differential diagnosis between primary and metastatic lung adenocarcinomas. The TA02-immunohistochemical evaluation was carried out using surgically resected materials of 109 cases of lung cancer (76 cases of primary lung cancer and 33 cases of metastatic lung adenocarcinoma from other organs), five cases with mesothelioma, four cases with atypical adenomatous hyperplasia (AAH) and five cases with tuberculoma of the lung. In 39 out of 43 (90.7%) primary lung adenocarcinomas, positive immunohistochemical reactivity with a granular cytoplasmic staining pattern was observed. Even though two out of seven (28.6%) large cell carcinomas showed positive results with a granular staining pattern, the immunohistochemical staining intensity was weak. The other cancerous lesions containing metastatic lung adenocarcinoma and mesothelioma were all completely negative. In comparison with the immunohistochemical reactivity of TA02 and SpA, TA02 was superior to SpA both in terms of positive rate and immunohistochemical intensity. We concluded that the evaluation of TA02 expression in lung tumorous lesions was very valuable for discriminating between primary and metastatic lung adenocarcinoma, and TA02 was superior to SpA as a discriminating marker.

Prognostic use of growth characteristics of early gastric cancer and expression patterns of apoptotic, cell proliferation, and cell adhesion proteins.

BACKGROUND AND OBJECTIVES: Selection of suitable treatment for early gastric cancers, such as endoscopic mucosal resection or the major surgical option of resection of the cancer together with a radical lymph node dissection, may be assisted by comparing the growth characteristics of the cancer with selected molecular characteristics. The results could be used to predict those cases that have a higher risk of developing secondary metastases. METHODS: A total of 1,196 Japanese patients with early gastric cancers (648 mucosal cancers and 548 submucosal) were included in the selection of two groups: a metastatic group made up 57 cancers with lymph node metastasis (9 mucosal, 48 submucosal), and a nonmetastatic group of 61 cases (6 mucosal, 55 submucosal) without lymph node metastasis. Growth characteristics of the cancers (superficially spreading, penetrating or invasive, lymph node metastasis) were compared with immunohistochemical expression of single-stranded DNA (ssDNA) protein (apoptosis indicator), bcl-2 and p53 (apoptosis-associated), Ki-67 (cell proliferation), and E-cadherin (cell adhesion) proteins. RESULTS: The lesions in the nonmetastatic group had higher levels of apoptosis and lower expression of bcl-2 than in the metastatic group, indicating an inhibitory role for apoptosis in malignant progression. Apoptosis was also higher in the superficial compared with the invasive lesions of both groups. The lesions in the metastatic group had higher p53 expression than that of the nonmetastatic group, whereas apoptosis in the metastatic group was lower than in the nonmetastatic group. An unproved explanation for this finding may be that, although increased, p53 was mutated and ineffective in promoting apoptotic control of metastatic progression. E-cadherin was decreased in the invasive lesions of both groups, indicating a greater ability of these cells to lose adhesion, to invade the submucosa, and to metastasize. Cell proliferation was highest in the superficial lesions of both metastatic and nonmetastatic groups. CONCLUSIONS: Early gastric cancers with low levels of apoptosis, increased bcl-2, and high levels of p53 expression are more likely to invade and metastasize.

Establishment of a new human cell line (EN) with TP53 mutation derived from endometrial carcinoma.

We present a new cell line, EN, established from an invasive endometrioid adenocarcinoma of the uterine corpus in 50-year-old patient. The cells show rapid growth in culture with a doubling time of 24.4 hours and high migration activity. Monolayer-cultured cells were polygonal in shape and showed a tendency to pile up without contact inhibition. Subcutaneous transplantation of the EN cells into nude mice formed solid tumors that were histologically diagnosed as adenocarcinoma, whereas no metastasis was observed. Cultured EN cells produced tissue polypeptide antigen. Genetic and molecular analyses revealed high telomerase activity and estrogen receptor beta but not alpha expression. Using the polymerase chain reaction-single strand conformation polymorphism technique, we have screened EN cells for TP53 mutation in exons 5-8. A mobility shift was observed in this cell line in exon 8. A nucleotide insertion (CGT-->CAGT) was detected at codon 273, which resulted in a creation of a stop codon at codon 308. This cell line thus appears to represent the development of a more malignant clone with divergent receptor function and growth behavior, and provides us with an interesting new tool for the study of tumorigenesis in the human endometrium.

Matrix metalloproteinase-26 is expressed in human endometrium but not in endometrial carcinoma.

BACKGROUND: The human matrix metalloproteinase (MMP)-26, also called matrilysin-2 or endometase, has been isolated as a matrilysin (MMP-7) homolog. Matrix metalloproteinase-26 was expressed in tissue samples from the placenta and endometrial tumors and its expression may be related to the development of endometrial carcinomas. METHODS: Total RNAs were isolated from 5 endometrial carcinoma cell lines, 36 normal endometrial tissue samples, 4 hyperplasia tissue samples, and from 24 endometrial carcinoma tissue samples. Reverse transcription-polymerase chain reation (RT-PCR) was performed to detect MMP-26 mRNA expression. To identify MMP-26 mRNA localization and protein expression, we performed in situ RT-PCR and immunohistochemistry, respectively. RESULTS: Reverse transcription-polymerase chain reaction analysis revealed that MMP-26 mRNA was expressed in 24 of 36 normal human endometrial tissue samples. However, MMP-26 mRNA expression was not detected in endometrial carcinoma cell lines nor in endometrial carcinoma tissue samples except for one case. Western blot analysis showed similar results. In situ RT-PCR analysis revealed that MMP-26 expression was localized in the epithelial glandular cells but faint expression was observed in the stromal cells. Subsequently, we separated endometrial tissues into epithelial glandular and stromal cells. Using RT-PCR, the purified epithelial glandular cells exhibited MMP-26 mRNA expression but the purified stromal cells did not. Immunohistochemical analyses revealed that MMP-26 protein expression is also limited to endometrial epithelial glandular cells but not to cancer cells. Therefore, MMP-26 expression is limited to normal epithelial glandular cells. CONCLUSIONS: We found a significant difference in MMP-26 expression in normal and malignant endometrial tissue samples, although its function is still unknown. These data suggest that MMP-26 may be a candidate for a new tumor marker for endometrial carcinomas.

The characteristics of early bronchogenic carcinoma evaluated by cytomorphological features.

The relationship between the cell features of central type early lung cancer and the degree of invasion to the bronchial wall was investigated. Bronchial brushing specimens were obtained from 19 cases of central type early lung cancer preoperatively and the resected specimens were pathologically examined. The cell features were classified into three types: Type I: low grade atypia without increased nuclear chromatin, Type II: moderate grade atypia with increased chromatin and Type III: high grade atypia with irregular shaped nucleus and increased chromatin. The expression of Type I cells was significant in cases of carcinoma in situ or microinvasion and Type II and III cells were observed more frequently in cases with extramuscular bronchial wall invasion. The cell features as well as endoscopic findings can provide a basis for the more precise staging of early stage lung cancer and the determination of therapeutic strategy.

Effect of survivin on cell proliferation and apoptosis in gastric cancer.

We investigated the effect of expression of survivin, an apoptosis inhibiting protein, on cellular proliferation and apoptosis in gastric cancer and assessed its relation to the pathological characteristics of gastric cancer. Resected gastric cancer specimens from 42 patients (intestinal type; 21 cases and diffuse type; 21 cases) were evaluated. There were no significant differences in the clinicopathologic factors between the two groups. Survivin mRNA expression was measured using real-time reverse transcription-polymerase chain reaction, and survivin protein expression was evaluated by immunohistochemical staining. The Ki-67 index was adopted for cell proliferation scoring, and the ss-DNA positive rate as an apoptotic index. The survivin mRNA expression inversely correlated with the apoptotic index (p<0.05). Survivin mRNA expression (p<0.001) and survivin protein expression (p<0.001) were significantly higher in the diffuse type than the intestinal type. In conclusion, gastric cancer avoids cellular death by survivin expression and this tendency was more conspicuous in diffuse type gastric cancer.

Keratocystoma of the parotid gland: a report of two cases of an unusual pathologic entity.

Benign salivary gland tumors composed of purely squamous cells are quite unusual and are not included in the World Health Organization classification. We have seen two benign parotid gland tumors characterized by multicystic spaces with stratified squamous linings and focal solid epithelial nests. Seifert et al. recently described such a case as a choristoma; we, however, herein propose a new designation, keratocystoma, for this unique tumor group, because of its distinctive histological features. These tumors occurred in men aged 18 and 38 years with enlarging parotid gland tumors. Both had largely similar gross and histological features, with some variations. The epithelium lining of the cysts showed apparent keratinization through a parakeratotic or orthokeratotic pathway without forming a granular cell layer. Stratification of the epithelium was always regularly oriented from the outer basal to the inner keratotic cell layer. Focally, the outer layer had bud-like protrusions. In some areas, solid squamous cell islands surrounded by basement membrane were enclosed within the collagenous stroma. These cystic and solid structures were randomly distributed, showing no definite lobular architecture. All of the tumor cells had uniform, bland nuclei and abundant eosinophilic cytoplasm. Scattered mitotic figures were observed, limited to the outer epithelial layer, and showed no abnormal patterns. Transformation from the parotid ductal epithelium to the tumor cells is evident. Foci of foreign-body reactions against keratin materials were present. Immunoreactivities for cytokeratins reconfirmed the nature of squamous differentiation of the tumor cells. Ki-67-positive cells were confined along the outer basal layer of the tumor epithelium. Tests for alpha-smooth muscle actin and S-100 protein were completely negative. Both patients had no evidence of recurrence 3 and 2 years after subtotal parotidectomy, respectively, without any additional therapy. We believe that this lesion represents a benign cystic neoplasm rather than a malignant tumor or pseudoneoplastic metaplastic condition. It is important to recognize that this peculiar benign tumor does originate from the salivary gland.

Apoptosis and cell proliferation in the development of gastric carcinomas: associations with c-myc and p53 protein expression.

BACKGROUND AND AIM: Patients with gastric carcinomas have a poor prognosis and low survival rates. The aim of the present paper was to characterize cellular and molecular properties to provide insight into aspects of tumor progression in early compared with advanced gastric cancers. METHODS: One hundred and nine graded gastric carcinomas (early or advanced stage, undifferentiated or differentiated type) with paired non-cancer tissue were studied to define the correlation between apoptosis (morphology, terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling), cell proliferation (Ki-67 expression, morphology) and expression and localization of two proteins frequently having altered expression in cancers, namely p53 and c-myc. RESULTS: Overall, apoptosis was lower in early stage, differentiated and undifferentiated gastric carcinomas compared with advanced-stage cancers. Cell proliferation was comparatively high in all stages. There was a high level of p53 positivity in all stages. Only the early- and advanced-stage undifferentiated cancers that were p53 positive had a significantly higher level of apoptosis (P < 0.05). Cell proliferation was significantly greater (P < 0.05) only in the early undifferentiated cancers that had either c-myc or p53-positivity. CONCLUSIONS: The results indicate that low apoptosis and high cell proliferation combine to drive gastric cancer development. The molecular controls for high cell proliferation of the early stage undifferentiated gastric cancers involve overexpression of both p53 and c-myc. Overexpression of p53 may also control cancer development in that its expression is associated with higher levels of apoptosis in early and late-stage undifferentiated, cancers.