PubMed Health⌕ Search

Biomedical subjects

Chiho Ohbayashi

Publications and source records attributed to Chiho Ohbayashi.

At least 19 recordsLinked to original sources
PubMed2006

Adenocarcinoma arising in gastric inverted hyperplastic polyp: a case report and review of the literature.

A 54-year-old man, found to have a submucosal tumor in the stomach by double contrast roentgenography, endoscopy, and endoscopic ultrasonography, underwent a laparoscopic partial gastrectomy. The pathological examination revealed that the lesion, measuring 45 mm x 35 mm, was an inverted hyperplastic polyp (IHP) located in the submucosal layer and consisting mostly of columnar cells resembling foveolar epithelium and pyloric gland cells. Notably, adenocarcinoma with adjacent dysplasia was observed in the submucosal glands. Transition from hyperplasia to dysplasia and from dysplasia to adenocarcinoma was noted. The adenocarcinoma component was intensely and diffusely positive for p53 overexpression, while the dysplasia component showed only weak and focal positivity, suggesting a role of p53 mutation in the dysplasia-carcinoma sequence. Gastric IHP is very rare, and only 31 cases (in 29 patients) have been reported. Five of these IHPs coexisted with gastric adenocarcinomas, which had all developed separately from the IHP lesions. Therefore, this is the first case of adenocarcinoma arising within gastric IHP itself.

Adenocarcinoma↗
PubMed2006

Increased expression of connexin 26 in the invasive component of lung squamous cell carcinoma: significant correlation with poor prognosis.

Reduced expression of connexins (Cxs), gap junction proteins, is frequently reported in malignant cell lines and tumors, whereas recent studies suggested that C x 26, a subtype of Cxs, might help tumor cells acquire malignant phenotypes. To examine this suggestion in the clinical setting, 50 lung squamous cell carcinomas (SCCs) were stained with the anti-C x 26 antibody. No C x 26-specific signals were detectable in 34 tumors (group I; 68%), whereas the remaining 16 were judged positive for C x 26 (group II; 32%). In 14 tumors of group II, C x 26-specific signals were detected not in all SCC cells but in SCC cells facing the tumor stroma or capsule, in which the signals were localized on the plasma membrane. Involved lymph nodes of group-II patients often contained metastatic foci consisting of all C x 26-positive cells. The proportion of C x 26-positive to C x 26-negative SCC cells in the metastatic nodes was larger than that in the corresponding primary tumors. C x 26-positive SCC cells seemed to be more invasive and metastatic than negative ones. Consistently, the 5-year cancer-specific survival rate of group-II patients was significantly lower than that of group-I patients (12.5 vs 38.9%; P=0.0391). Multivariate analysis demonstrated that C x 26 expression (P=0.0448) as well as pathological stage (P=0.0338) and vascular invasion (P=0.0191) were independent, significant prognostic predictors. These results suggest that C x 26 may represent an essential effector for controlling the biological aggressiveness of lung SCC tumor.

Biomarkers, Tumor↗
PubMed2006

His239Arg SNP of HRAD9 is associated with lung adenocarcinoma.

BACKGROUND: It was previously reported that a functional human (h) Rad9 protein accumulated in the nuclei of non-small cell lung carcinoma (NSCLC) cells. Those experiments, however, did not examine whether the hRad9 gene was mutated in those cells. The sequence of the HRAD9 gene in NSCLC cells was investigated. METHODS: The sequence of the HRAD9 was examined in tumor and peripheral normal lung tissues obtained from 50 lung adenocarcinoma patients during surgery. The expression of its mRNA using reverse transcription polymerase chain reaction (RT-PCR) was also examined. RESULTS: No sequence alterations were detected in the HRAD9 gene, which was found to be normally transcribed in surgically resected lung carcinoma cells. However, in eight (16.0%) cases a single nucleotide polymorphism (SNP) was observed at the second position of codon 239 (His/Arg heterozygous variant) of the gene. This frequency was significantly higher than that found in the normal population. CONCLUSIONS: Whereas the capacity to produce a functional hRad9 protein was intact in lung adenocarcinoma cells, a nonsynonymous SNP of HRAD9 was detected that might be associated with the development of lung adenocarcinoma.

Adenocarcinoma↗
PubMed2005

Accumulation of hRad9 protein in the nuclei of nonsmall cell lung carcinoma cells.

BACKGROUND: DNA damage sensor proteins have received much attention as upstream components of the DNA damage checkpoint signaling pathway that are required for cell cycle control and the induction of apoptosis. Deficiencies in these proteins are directly linked to the accumulation of gene mutations, which can induce cellular transformation and result in malignant disease. METHODS: Using 48 sets of tumor tissue specimens and peripheral normal lung tissue specimens from 48 patients with nonsmall cell lung carcinoma (NSCLC) who underwent surgery, the authors investigated the expression of hRad9 protein, a member of the human DNA damage sensor family, using immunohistochemical and Western blot analyses. RESULTS: Immunohistochemical analysis detected the accumulation of hRad9 in the nuclei of tumor cells in 16 tumor tissue specimens, (33% of tumor tissue specimens examined). Western blot analysis also revealed elevated levels of phosphorylated hRad9 protein in NSCLC cells that was accompanied by the detection of phosphorylated Chk1, a protein kinase that regulates the downstream signaling of the DNA damage checkpoint pathway. Furthermore, strong expression of hRad9 was correlated with an increase in Ki-67 expression index in the tumor cells that were examined. CONCLUSIONS: The findings made in the current study suggest that Rad9 expression may play an important role in cell cycle control in NSCLC cells and may influence NSCLC cell phenotype.

Adult↗
PubMed2005

Thin-section multiplanar reformats from multidetector-row CT data: utility for assessment of regional tumor extent in non-small cell lung cancer.

PURPOSE: To determine the clinical utility of thin-section multiplanar reformats (MPRs) from multidetector-row CT (MDCT) data sets for assessing the extent of regional tumors in non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: Sixty consecutive NSCLC patients, who were considered candidates for surgical treatment, underwent contrast-enhanced MDCT examinations, surgical resection and pathological examinations. All MDCT examinations were performed with a 4-detector row computed tomography (CT). From each raw CT data set, 5mm section thickness CT images (routine CT), 1.25 mm section thickness CT images (thin-section CT) and 1.25 mm section thickness sagittal (thin-section sagittal MPR) and coronal images (thin-section coronal MPR) were reconstructed. A 4-point visual score was used to assess mediastinal, interlobar and chest wall invasions on each image set. For assessment of utility in routine clinical practice, mean reading times for each image set were compared by means of Fisher's protected least significant difference (PLSD) test. A receiver operator characteristic (ROC) analysis was performed to determine the diagnostic capability of each of the image data sets. Finally, sensitivity, specificity and accuracy of the reconstructed images were compared by McNemar test. RESULTS: Mean reading times for thin-section sagittal and coronal MPRs were significantly shorter than those for routine CT and thin-section CT (p<0.05). Areas under the curve (Azs) showing interlobar invasion on thin-section sagittal and coronal MPRs were significantly larger than that on routine CT (p=0.03), and the Az on thin-section sagittal MPR was also significantly larger than that on routine CT (p=0.02). Accuracy of chest wall invasion by thin-section sagittal MPR was significantly higher than that by routine CT (p=0.04). CONCLUSION: Thin-section multiplanar reformats from multidetector-row CT data sets are useful for assessing the extent of regional tumors in non-small cell lung cancer patients.

Adult↗
PubMed2005

Aggressive syringomatous carcinoma of the orbit.

A 68-year-old woman with an unusual tumor involving the right orbit presented with painful exophthalmos of the right eye. Excision biopsy of her right eyelid was performed. The specimen showed ductal differentiation with comma-like extensions identical to syringoma. Cellular atypia, an invasive growth pattern, and remarkable perineural invasion led to the diagnosis of syringomatous carcinoma. Magnetic resonance imaging showed that the tumor exhibited maxillary involvement, invading the supraorbital fissure and bone of the middle skull base. The patient underwent craniofacial resection and has been alive with no sign of recurrence for 2 years. This case suggests that wide excision of these tumors with a clear surgical margin using skull base surgical techniques may offer a good prognosis.

Case Reports↗
PubMed2005

Better choice of fixatives provides better histological details of the alveolar-capillary interface.

AIMS: To evaluate lung disease, pulmonary tissues should be fixed by inflation. However, many histological sections prepared after inflation fixation show wire-like alveolar septa with capillary collapse. We investigated the reason for this artefact. METHODS: To evaluate the effect of fixatives, we used the following commercially available solutions: regular 10% neutral buffered formalin (NBF), 20% NBF, 10% and 5% formalin prepared by diluting the 20% NBF, modified formalin solution as a substitute for 10% NBF, and 10% formalin prepared by diluting the 100% formalin without any buffers. RESULTS: The osmolarity of the fixative was found to be responsible for the collapse artefact. Ten per cent formalin, prepared by diluting 100% formalin, the commercially available substitute for 10% NBF, and 5% formalin prepared by diluting 20% NBF, yielded the best pulmonary tissue morphology, including that of the alveolar-capillary interface. CONCLUSIONS: Pulmonary physicians and pulmonary pathologists should use a suitable fixative solution for obtaining a better pulmonary architecture as well as to preserve the tissue block in optimal condition for future assessment of pulmonary diseases.

Artifacts↗
PubMed2005

Estimation of contrast of refraction contrast imaging compared with absorption imaging-basic approach.

PURPOSE: We discuss the usefulness of the refraction contrast method using highly parallel X-rays as a new approach to minute lung cancer detection. The advantages of refraction contrast images are discussed in terms of contrast, and a comparison is made with absorption images. MATERIALS AND METHODS: We simulated refraction contrast imaging using globules with the density of water in air as models for minute lung cancer detection. The contrast intensified by bright and dark lines was compared on a globule with the contrast of absorption images. We adopted the Monte Carlo simulation to determine the strength of the profile curve of the photon counts at the detector. RESULTS: The obtained contrasts were more intense by two to three digits than those obtainable with the absorption contrast imaging method. CONCLUSION: The contrast in refraction contrast imaging was more intense than that obtainable with absorption contrast imaging. A two to three digit improvement in contrast means that it is possible to greatly reduce the exposure dose necessary for imaging. Therefore, it is expected to become possible to detect the interfaces of soft tissues, which are difficult to capture with conventional absorption imaging, at low dosages and high resolution.

Absorption↗
PubMed2004

Dynamic MR imaging: value of differentiating subtypes of peripheral small adenocarcinoma of the lung.

PURPOSE: To determine the utility of dynamic magnetic resonance imaging (MRI) in the differential subtyping of small adenocarcinomas of the lung. MATERIALS AND METHODS: Twenty-nine pathologically diagnosed peripheral adenocarcinomas (less than 20 mm in diameter) underwent dynamic contrast-enhanced MRI. Maximum relative enhancement ratio, slope of enhancement, and corrected start time of enhancement were calculated from signal intensity-time curve of pulmonary lesion for each subject, and were statistically compared among bronchioloalveolar carcinoma (BAC) group (7 cases), mixed BAC group (10 cases), and adenocarcinoma group (12 cases). RESULTS: Maximum relative enhancement ratio (P<0.001) and slope of enhancement (P<0.001) of BAC group were significantly higher than those of mixed BAC and adenocarcinoma groups. Start times of BAC group were significantly earlier than those of mixed BAC (P=0.0001) and adenocarcinoma groups (P<0.0001). Adapting the thresholds values of MR indexes from the positive tests, sensitivity, specificity, positive predictive value, negative predictive value and accuracy for differentiating BAC from other subtypes were 85.7, 100.0, 100.0, 95.7, and 96.6%, respectively. CONCLUSIONS: Dynamic MRI is useful for differentiating subtypes of small peripheral adenocarcinoma.

Adenocarcinoma↗
PubMed2004

Correlation between computed tomographic findings, bronchioloalveolar carcinoma component, and biologic behavior of small-sized lung adenocarcinomas.

OBJECTIVE: Differentiation of bronchioloalveolar carcinoma from other subtypes of lung adenocarcinomas is important in the preoperative assessment of patients. We examined the biologic aggressiveness of small-sized adenocarcinomas according to the pathologically defined bronchioloalveolar carcinoma degree and its correlation with computed tomography findings. In addition, we attempted to predict which patients were suitable for a lesser resection. METHODS: Of 424 consecutive patients who underwent operation for primary lung cancer in the last 3 years, 114 with a histopathologically proven adenocarcinoma 3 cm or less in diameter underwent complete removal of the primary tumor. We examined the characteristics of patients classified into 3 groups based on the proportion of the bronchioloalveolar carcinoma component: 0% to 20% (n = 40), 21% to 50% (n = 38), and 51% to 100% (n = 36). We also investigated the correlation of the bronchioloalveolar carcinoma component with computed tomography findings such as ground-glass opacity (defined as a hazy increase on the lung window) and tumor shadow disappearance rate (defined as the ratio of the tumor area of the mediastinal window to that of the lung window). RESULTS: Male gender (P =.0001), advanced pathologic stage (P =.001), larger size of the tumor (P =.004), nodal involvement (P =.04), pleural invasion (P =.0003), lymphatic invasion (P =.002), and vascular invasion (P =.0002) were observed more often among patients with a smaller proportion of bronchioloalveolar carcinoma. A positive and significant correlation was found between the rate of bronchioloalveolar carcinoma component and ground-glass opacity (R(2) = 0.488, P <.0001) and tumor shadow disappearance rate (R(2) = 0.727, P <.0001). As an independent predictor of nodal status, tumor shadow disappearance rate (P =.015) and bronchioloalveolar carcinoma component (P =.015), as well as tumor size, were significantly valuable, although ground-glass opacity proportion (P =.086) was marginally informative. CONCLUSIONS: Small-sized adenocarcinomas with a greater ratio of bronchioloalveolar carcinoma component showed less aggressive behavior. Both tumor shadow disappearance rate and ground-glass opacity ratios, which are obtained preoperatively, were well associated with bronchioloalveolar carcinoma ratios, which are determined postoperatively. Furthermore, tumor shadow disappearance rate had a stronger impact as a predictor of bronchioloalveolar carcinoma component. Preoperative assessment of tumor shadow disappearance rate may be useful to identify patients requiring a less extensive pulmonary resection.

Adenocarcinoma↗
PubMed2004

Transthoracic CT-guided biopsy with multiplanar reconstruction image improves diagnostic accuracy of solitary pulmonary nodules.

OBJECTIVE: To evaluate the utility of multiplanar reconstruction (MPR) image for CT-guided biopsy and determine factors of influencing diagnostic accuracy and the pneumothorax rate. MATERIALS AND METHODS: 390 patients with 396 pulmonary nodules underwent transthoracic CT-guided aspiration biopsy (TNAB) and transthoracic CT-guided cutting needle core biopsy (TCNB) as follows: 250 solitary pulmonary nodules (SPNs) underwent conventional CT-guided biopsy (conventional method), 81 underwent CT-fluoroscopic biopsy (CT-fluoroscopic method) and 65 underwent conventional CT-guided biopsy in combination with MPR image (MPR method). Success rate, overall diagnostic accuracy, pneumothorax rate and total procedure time were compared in each method. Factors affecting diagnostic accuracy and pneumothorax rate of CT-guided biopsy were statistically evaluated. RESULTS: Success rates (TNAB: 100.0%, TCNB: 100.0%) and overall diagnostic accuracies (TNAB: 96.9%, TCNB: 97.0%) of MPR were significantly higher than those using the conventional method (TNAB: 87.6 and 82.4%, TCNB: 86.3 and 81.3%) (P < 0.05). Diagnostic accuracy were influenced by biopsy method, lesion size, and needle path length (P < 0.05). Pneumothorax rate was influenced by pathological diagnostic method, lesion size, number of punctures and FEV1.0% (P < 0.05). CONCLUSION: The use of MPR for CT-guided lung biopsy is useful for improving diagnostic accuracy with no significant increase in pneumothorax rate or total procedure time.

Adolescent↗
PubMed2004

High-grade neuroendocrine carcinoma of the lung presenting an unusual spread mimicking pleural mesothelioma associated with dermatomyositis.

Neuroendocrine tumors of the lung comprise a heterogeneous group of tumors that represents a spectrum of disease from typical carcinoid tumors to the high-grade neuroendocrine carcinomas (large-cell neuroendocrine carcinomas and small-cell carcinomas). The high-grade neuroendocrine carcinomas are characterized by early metastasis and poor prognosis. The peripheral location and especially the massive pleural spread are rare for a high-grade neuroendocrine carcinoma. We report a case in which a high-grade neuroendocrine carcinoma, associated with dermatomyositis, presented an unusual pattern of progression, mimicking malignant pleural mesothelioma on diagnostic imaging.

Carcinoma, Neuroendocrine↗
PubMed2004

Metastases in mediastinal and hilar lymph nodes in patients with non-small cell lung cancer: quantitative and qualitative assessment with STIR turbo spin-echo MR imaging.

PURPOSE: To evaluate short inversion time inversion-recovery (STIR) turbo spin-echo (TSE) magnetic resonance (MR) imaging for detection of metastases in lymph nodes by using quantitative and qualitative analyses. MATERIALS AND METHODS: One hundred ten patients (68 men and 42 women) with non-small cell lung cancer who ranged in age from 36 to 82 years (mean age, 64 years) were examined with respiratory-triggered STIR TSE MR imaging. Ratios of signal intensity in a lymph node to that in a 0.9% saline phantom (lymph node-saline ratios [LSRs]) for all lymph nodes were classified into three groups according to nodal short-axis diameter. LSRs of each group were compared by using pathologic diagnosis as the standard of reference. For quantitative analysis, the LSR threshold value for a positive test was determined on a per-node basis and tested for ability to enable a correct diagnosis on a per-patient basis. For qualitative analysis, signal intensities of lymph nodes were assessed by using a five-point visual scoring system. Results of quantitative and qualitative analyses were compared on a per-patient basis with McNemar testing. RESULTS: In 110 patients, 92 of 802 lymph nodes were pathologically diagnosed as containing metastases, while 710 lymph nodes did not contain metastases. Mean LSR in the lymph node group with metastasis was higher than that in the group without metastasis (P <.05). When an LSR of 0.6 was used as the positive-test threshold at quantitative analysis, sensitivity was 93% (37 of 40 patients) and specificity was 87% (61 of 70 patients) on a per-patient basis. With a score of 4 as the positive-test threshold at qualitative analysis, sensitivity was 88% (35 of 40 patients) and specificity was 86% (60 of 70 patients) on a per-patient basis. There was no significant difference (P >.05) between results of quantitative and those of qualitative analysis. CONCLUSION: Quantitative and qualitative analyses of STIR TSE MR images enable differentiation of lymph nodes with metastasis from those without. Qualitative analysis can substitute for quantitative analysis of STIR TSE MR imaging data.

Adult↗
PubMed2004

Synovial sarcoma of the neck.

BACKGROUND: Synovial sarcoma is a soft tissue sarcoma rarely seen in the head and neck. Due to its rarity and morphologic variations, diagnosis is difficult in most cases. METHOD: A case of synovial sarcoma arising in the upper neck is presented. The detection of the specific chromosomal translocation t(X;18)(p11.2;q11.2) is also described. RESULT: A specific chimeric gene, the SSX-SYT fusion gene, was identified in the formalin-fixed paraffin-embedded surgical specimen using the reverse-transcription polymerase chain reaction (RT-PCR) technique. CONCLUSION: Synovial sarcoma contains a characteristic chromosomal translocation, which serves as a useful diagnostic tool. RT-PCR technique has enabled to detect this specific translocation not only in fresh tissues but also in archival paraffin-embedded specimens.

Adult↗
PubMed2003

Clinical implication and prognostic significance of the tumor suppressor TSLC1 gene detected in adenocarcinoma of the lung.

BACKGROUND: Recently, the TSLC1 (tumor suppressor in lung cancer 1) gene has been identified as a novel tumor suppressor in human nonsmall cell lung carcinoma. To the authors' knowledge, the clinical relevance of TSLC1 gene expression has not been studied using patient data and surgical samples. The current study was designed to evaluate whether the TSLC1 gene can serve as a target for the prognostic determination of patients with pulmonary adenocarcinoma. METHODS: A total of 38 patients who were surgically treated for proven primary lung adenocarcinoma were enrolled in the current study. Surgical specimens were examined for TSLC1 protein expression immunohistochemically and by Western blot analysis. The correlation between levels of TSLC1 expression and pathologic characteristics, as well as prognosis, was investigated. RESULTS: All patients underwent a potentially curative resection of their tumor. TSLC1 antigen expression as evaluated by immunohistochemistry was confirmed by immunoblotting. The expression of TSLC1 protein was found to be inversely correlated with advanced disease stage, lymph node involvement, lymphatic permeation, and vascular invasion. The 4-year overall survival rates of patients with a tumor demonstrating high (> 70% positive cells [n = 14 patients]), intermediate (20-70% positive cells [n = 10 patients]), and low (< 20% positive cells [n = 14 patients]) expression of the TSLC1 antigen were 84%, 28%, and 7%, respectively. In addition, the disease-free survival of patients with a tumor that demonstrated a high percentage of TSLC1 protein-positive cells was reported to be significantly better than that of patients with a tumor that showed a low percentage of TSLC1 protein-positive cells. CONCLUSIONS: The loss or reduction of TSLC1 expression in resected lung adenocarcinoma cases was associated with a poor prognosis, indicating that TSLC1 represents a central effector gene for controlling the biologic aggressiveness of the tumor and that it is an essential biomarker for predicting patient prognosis. These data may help to detect those patients at high risk for recurrence who might benefit from additional therapeutic strategies such as adjuvant therapy.

Adenocarcinoma↗
PubMed2003

CT-guided transthoracic needle aspiration biopsy of small (< or = 20 mm) solitary pulmonary nodules.

OBJECTIVE: The purpose of our study was to determine the diagnostic accuracy and to analyze the factors influencing the diagnostic accuracy and incidences of pneumothorax and chest tube insertion rates for percutaneous CT-guided needle biopsy of small (< or = 20 mm) solitary pulmonary nodules. SUBJECTS AND METHODS: One hundred sixty-two patients with 162 small solitary pulmonary nodules underwent CT-guided transthoracic needle aspiration biopsy. The overall diagnostic accuracy, pneumothorax rate, and chest tube insertion rate were calculated. Factors influencing the diagnostic accuracy and pneumothorax rate were statistically evaluated. Influencing factors, diagnostic accuracies, pneumothorax rates, and chest tube insertion rates were statistically compared. RESULTS: Overall diagnostic accuracy, pneumothorax rate, and chest tube insertion rate were 77.2%, 28.4%, and 2.5%, respectively. Diagnostic accuracy was significantly affected by length of needle path and lesion size (p < 0.05). The pneumothorax rate was significantly affected by the percentage of predicted forced expiratory volume in 1 sec, the number of punctures, and the needle path length (p < 0.05). The chest tube insertion rate was significantly affected by the number of punctures (p < 0.05). For diagnostic accuracy, needle path lengths of 40 mm or less and lesion sizes greater than 10 mm were significantly more accurate than other factors (p < 0.05). For pneumothorax rates, a percentage of predicted forced expiratory volume in 1 sec of greater than 70%, a single puncture, and a needle path length of 40 mm or less were significantly lower than other factors (p < 0.05). CONCLUSION: CT-guided transthoracic needle aspiration biopsy is a useful diagnostic tool for small solitary pulmonary nodules smaller than 20 mm in diameter. The diagnostic accuracy is significantly improved for large (> 10 mm) lesion size and short (< or = 40 mm) needle path length.

Adult↗
PubMed2002

Local levels of interleukin-1beta, -4, -6 and tumor necrosis factor alpha in an experimental model of murine osteomyelitis due to staphylococcus aureus.

The purpose of this study is to evaluate local levels of interleukin-1 beta (IL-1 beta), -4 (IL-4), -6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha), in a model of murine osteomyelitis due to Staphylococcus aureus. Cytokine levels in supernatants derived from bone homogenates were determined by enzyme-linked immunosorbent assay, for 28 days following the direct implantation of murine tibiae with S.aureus. Levels of IL-1 beta and IL-6 in infected bone were elevated in the early post-infection period and then decreased. In contrast, TNF-alpha levels remained elevated 3 to 28 days post-infection, while IL-4 levels were elevated late in the course of infection. The histopathology of infected bone showed predominant infiltration of inflammatory cells and bone resorption 3 to 7 days after infection, and bone resorption and adjacent areas of formation 14 to 28 days after infection. These results suggest that the elevated IL-1 beta and IL-6 levels induced by infection may be related to bone damage mainly in the early phase of infection, and that TNF-alpha and IL-4 may at least in part be associated with histopathological changes, including both bone resorption and formation in the later phase of this osteomyelitis model.

Animals↗