Yoshitomo Okumura

Hyogo College of Medicine, Nishinomiya, Hyogo-ken, Japan

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Publications (23)53.03 Total impact

  • Article: Frequency of epidermal growth factor receptor mutations in Bangladeshi patients with adenocarcinoma of the lung.
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    ABSTRACT: BACKGROUND: Worldwide studies on lung adenocarcinoma have demonstrated a genetic divergence of the epidermal growth factor receptor (EGFR) pathway according to ethnicity, such as higher frequency of activated EGFR mutations among East Asian patients. However, such information is still lacking in some developing countries. METHODS: We investigated the frequency of EGFR mutations among Bangladeshi patients with adenocarcinoma of the lung. Fine-needle aspiration tissue samples were collected from 61 Bangladeshi patients. Polymerase chain reaction-single-strand conformation polymorphism was performed on extracted DNA for mutational analysis of EGFR exons 19 and 21. RESULTS: EGFR mutations were found in 14 of 61 (23.0 %) Bangladeshi patients. There was no significant difference in EGFR mutation rate with regard to patient's age, sex, smoking history, clinical stage of lung cancer, subtypes of adenocarcinoma, and tumor differentiation. CONCLUSION: The present study revealed that the EGFR mutation rate in Bangladeshi patients with adenocarcinoma of the lung was higher than in African-American, Arabian, and white Caucasian patients, and was lower than in East Asia.
    International Journal of Clinical Oncology 01/2013; · 1.41 Impact Factor
  • Article: Circulating Endothelial Cell (CEC) as a Diagnostic and Prognostic Marker in Malignant Pleural Mesothelioma (MPM).
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    ABSTRACT: BACKGROUND: The purpose of this study was to investigate the diagnostic and prognostic value of circulating endothelial cell (CEC), a potential surrogate of tumor angiogenesis, in malignant pleural mesothelioma (MPM). METHODS: We prospectively evaluated CEC count in 4.0 mL of peripheral blood sampled from patients with a suspicion of MPM. An automated system was used to capture CECs with an anti-CD146 antibody. RESULTS: Of 109 eligible patients, 30 were finally diagnosed with non-malignant diseases, and 79 were with MPM. CEC count was significantly higher in MPM patients than in NM patients (mean CEC count, 120.3 and 39.9, respectively; P = 0.001), and a receiver operating characteristic (ROC) curve analysis showed that CEC provided a significant diagnostic performance in discrimination between MPM and nonmalignant diseases with an area under curve (AUC-ROC) of 0.700 (95 % confidence interval [95 % CI], 0.595-0.806; P = 0.001). Among MPM patients, CEC count was positively correlated with intratumoral microvessel density (MVD), a measurement of tumor angiogenesis (Spearman correlation coefficiency [r] = 0.444; P = 0.001). Higher CEC count (>50) was significantly associated with a poor prognosis (median overall survival, 11.4 months [95 % CI, 7.6-15.2] for higher CEC count patients versus 20.1 months [95 % CI, 16.0-24.2] for lower CEC count patients; P = 0.028). A multivariate analysis showed that higher CEC count was a significant and independent factor to predict a poor prognosis (hazard ratio [HR], 2.24, [95 % CI, 1.24-4.43]; P = 0.009). CONCLUSIONS: CEC, as a surrogate of tumor angiogenesis, was a promising marker in diagnosis and prediction of prognosis in MPM.
    Annals of Surgical Oncology 07/2012; · 4.17 Impact Factor
  • Article: Frequent inactivation of the BAP1 gene in epithelioid-type malignant mesothelioma.
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    ABSTRACT: In the present study, we analyzed genomic alterations of BRCA1-associated protein 1 (BAP1) in 23 malignant mesotheliomas (MMs), 16 epithelioid and seven non-epithelioid, consisting of 18 clinical specimens and five established cell lines. In examining these samples for homozygous deletions and sequence-level mutations, we found biallelic BAP1 gene alterations in 14 of 23 MMs (61%). Seven of these 14 MMs had homozygous deletions of the partial or entire BAP1 gene, another five had sequence-level mutations, including small deletions, a nonsense mutation, and missense mutations with additional monoallelic deletions, and the remaining two had homozygous mutations without allelic loss. All but one of the 14 BAP1 gene mutations were found in the epithelioid-type MMs; BAP1 mutations were found in 13 of 16 epithelioid-type MMs, but in only one of seven non-epithelioid-type MMs (13/16 vs 1/7; P = 0.005). There was no BAP1 mRNA expression in MMs with biallelic deletion and repressed expression was confirmed in MM specimens with deletion/mutation as compared with Met5a, SV40-transformed normal mesothelial cells. Western blot showed that seven of eight epithelioid MMs analyzed were BAP1 negative. Immunostaining with anti-BAP1 antibody in normal lung tissues revealed clear nuclear staining of normal mesothelial cells. No nuclear staining was observed among BAP1 mutation-positive MM tumors, whereas nuclear staining was observed among BAP1 mutation-negative MM tumors. These results suggest that the lack of the tumor suppressor BAP1 may be more specifically involved in the pathogenesis of epithelioid MM rather than non-epithelioid MM, and would be useful for diagnosis of epithelioid-type MM.
    Cancer Science 02/2012; 103(5):868-74. · 3.33 Impact Factor
  • Article: Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy.
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    ABSTRACT: Malignant pleural mesothelioma (MPM) remains suffering poor prognosis in spite of recent diagnostic and therapeutic progress. Although there is currently no established evidence, early diagnosis and early intervention may play a key role to improve prognosis of MPM, similarly to other malignancies. As pleural effusion is usually the first clinical sign of MPM, pleural effusion cytology is often the first diagnostic examination to be carried out. Since the sensitivity of pleural effusion cytology is approximately 60%, however, false-negative diagnosis is given to almost half of true MPM patients at this clinical step. One practical way to reduce the number of misdiagnosed MPM is to encourage performing thoracoscopic pleural biopsy unless definitive diagnosis other than MPM is established. There still remain a considerable number of patients with radiological/thoracoscopic T0 MPM who are misdiagnosed with nonspecific pleuritis after a complete investigation including thoracoscopic biopsies. Such patients will turn out to be malignant during follow-up period, although they have the best opportunity for long-term survival if only early therapeutic intervention is given. Currently, we are performing diagnostic total parietal pleurectomy in highly selected patients, who are characterized with strong clinical suspicion, positive pleural effusion cytology but uncertain pathological diagnosis, excellent cardiopulmonary reserve, and with written informed consent for highly invasive diagnostic surgery for pathologically unproven disease.
    International Journal of Clinical Oncology 02/2012; 17(1):33-9. · 1.41 Impact Factor
  • Article: Frequent deletion of 3p21.1 region carrying semaphorin 3G and aberrant expression of the genes participating in semaphorin signaling in the epithelioid type of malignant mesothelioma cells.
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    ABSTRACT: Array-based comparative genomic hybridization analysis was performed on 21 malignant mesothelioma (MM) samples (16 primary cell cultures and 5 cell lines) and two reactive mesothelial hyperplasia (RM) primary cell cultures. The RM samples did not have any genomic losses or gains. In MM samples, deletions in 1p, 3p21, 4q, 9p21, 16p13 and 22q were detected frequently. We focused on 3p21 because this deletion was specific to the epithelioid type. Especially, a deletion in 3p21.1 region carrying seven genes including SEMA3G was found in 52% of MM samples (11 of 14 epithelioid samples). The allele loss of 3p21.1 might be a good marker for the epithelioid MM. A homozygous deletion in this region was detected in two MM primary cell cultures. A heterozygous deletion detected in nine samples contained the 3p21.1 region and 3p21.31 one carrying the candidate tumor suppressor genes such as semaphorin 3F (SEMA3F), SEMA3B and Ras association (RalGDS/AF-6) domain family member 1 (RASSF1A). SEMA3B, 3F and 3G are class 3 semaphorins and inhibit growth by competing with vascular endothelial growth factor (VEGF) through binding to neuropilin. All MM samples downregulated the expression of more than one gene for SEMA3B, 3F and 3G when compared with Met5a, a normal pleura-derived cell line. Moreover, in 12 of 14 epithelioid MM samples the expression level of SEMA3A was lower than that in Met5a and the two RM samples. An augmented expression of VEGFA was detected in half of the MM samples. The expression ratio of VEGFA/SEMA3A was significantly higher in the epithelioid MMs than in Met5a, RMs and the non-epithelioid MMs. Our data suggest that the downregulated expression of SEMA3A and several SEMA3s results in a loss of inhibitory activities in tumor angiogenesis and tumor growth of VEGFA; therefore, it may play an important role on the pathogenesis of the epithelioid type of MM.
    International Journal of Oncology 08/2011; 39(6):1365-74. · 2.40 Impact Factor
  • Article: Diagnosis of synchronous primary lung adenocarcinomas based on epidermal growth factor (EGFR) gene status: A case report.
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    ABSTRACT: The diagnosis of multiple primary lung cancer is sometimes difficult when multiple lung tumors with the same histologic type are identified. We now present a case of synchronous double primary lung adenocarcinomas (one in the right upper lobe and another in the right middle lobe) diagnosed based on mutational analysis of the epidermal growth factor receptor (EGFR) gene, although clinico-pathological findings suggested the diagnosis of intrapulmonary metastasis. After complete resection, pathological sections revealed the similar pathological features of two adenocarcinomas and unexpected subcarinal nodal metastasis. As the L858R mutation within exon 21 of the EGFR gene was identified in the middle-lobe tumor and the subcarinal node but not in the upper-lobe tumor, we diagnosed as double primary cancers. Local mediastinal recurrence after operation has been well-controlled with administration of gefitinib, a EGFR-tyrosine kinase inhibitor, and mutational analysis of the EGFR gene provided important information not only in the diagnosis of double primary cancers but also in decision-making of selection of chemotherapeutic agent.
    Lung cancer (Amsterdam, Netherlands) 03/2010; 68(3):498-500. · 3.14 Impact Factor
  • Article: Reply.
    The Annals of thoracic surgery 12/2009; 88(6):2071. · 3.74 Impact Factor
  • Article: Circulating tumor cell as a diagnostic marker in primary lung cancer.
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    ABSTRACT: To investigate the diagnostic performance of circulating tumor cells (CTC) in discrimination between primary lung cancer and nonmalignant diseases as well as in prediction of distant metastasis. Patients and Methods: We prospectively evaluated CTCs in 7.5-mL samples of peripheral blood sampled from patients with a suspicion or a diagnosis of primary lung cancer. A semiautomated system was used to capture CTCs with an antibody against epithelial cell adhesion molecule. Of 150 eligible patients, 25 were finally diagnosed as having nonmalignant disease, and 125 were diagnosed as having primary lung cancer with (n = 31) or without (n = 94) distant metastasis. CTCs were detected in 30.6% of lung cancer patients and in 12.0% of nonmalignant patients. CTC count was significantly higher in lung cancer patients than in nonmalignant patients, but a receiver operating characteristic (ROC) curve analysis showed an insufficient capability of the CTC test in discrimination between lung cancer and nonmalignant diseases with an area under ROC curve of 0.598 (95% confidence interval, 0.488-0.708; P = 0.122). Among lung cancer patients, CTC count significantly increased along with tumor progression, especially with development of distant metastasis. The area under ROC curve for CTC count in prediction of distant metastasis was 0.783 (95% confidence interval, 0.679-0.886; P < 0.001). When patients with one or more CTCs were judged as having metastatic disease, sensitivity and specificity of the CTC test were 71.0% and 83.0%, respectively. CTC is a useful surrogate marker of distant metastasis in primary lung cancer.
    Clinical Cancer Research 11/2009; 15(22):6980-6. · 7.74 Impact Factor
  • Article: Well-differentiated papillary mesothelioma with invasion to the chest wall.
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    ABSTRACT: Well-differentiated papillary mesothelioma (WDPM) is an uncommon tumor with a papillary architecture, bland cytologic features, a tendency toward superficial spread without invasion, and good prognosis with prolonged survival. WDPM occurs primarily in the peritoneum of women, but also rarely in the pleura. We here report a case of 48-year-old woman who developed WDPM in the pleura with no history of asbestos exposure. Tumors were multifocal and widespread with a velvety appearance on the surface of parietal and visceral pleurae resected by extrapleural pneumonectomy (EPP). Tumors showed papillary structures with fibrovascular cores and lined by epithelioid cells. Immunohistochemically, these epithelioid tumor cells were positive for epithelial membrane antigen (EMA), a marker of malignant mesothelioma, with more than 50% positive for p53. Tumor cells microinvaded into subpleural parenchyma of the lung and minimally spread to adipose tissues of the mediastinal lesion. In addition, tumor cells invaded into the chest wall with a trabecular or glandular architecture. Based on these findings, this case is pathologically considered as WDPM of the pleura with malignant potential.
    Lung cancer (Amsterdam, Netherlands) 10/2009; 67(2):244-7. · 3.14 Impact Factor
  • Article: Circulating tumor cells in pulmonary venous blood of primary lung cancer patients.
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    ABSTRACT: Circulating tumor cells in peripheral blood (CTC) is a potential surrogate of distant metastasis, which is the critical factor influencing decision making regarding therapy and prognosis of primary lung cancer patients. After our preliminary study showing that CTCs were detected in peripheral blood in 29.4% of resectable lung cancer patients, we conducted a prospective study on CTC in pulmonary vein (PV) blood because tumor cells apart from the primary tumor may circulate after passing through the drainage PV. A total of 30 consecutive lung cancer patients who underwent thoracotomy were included. The CTCs in peripheral blood and in PV blood from the primary tumor site were quantitatively examined with the CellSearch system, and the numbers of CTCs per 7.5 mL peripheral and PV blood in each patient were represented as periCTC count and pvCTC count, respectively. Circulating tumor cell was detected in peripheral blood in 5 patients (16.7%; the periCTC count was 1 in 2 patients; and 2, 3, and 16 in 1 patient each), and the incidence of positive periCTC was higher in squamous carcinoma patients than in adenocarcinoma patients (p = 0.028). Circulating tumor cell was detected in PV blood in most patients (29 of 30, 96.7%), and the mean and median pvCTC counts were 1,195 and 81, respectively (range, 0 to 10,034). There was no significant correlation between pvCTC count and any other patient characteristic, including periCTC count. In resectable lung cancer, CTC was positive in peripheral blood of some patients and in PV blood of most patients. A long-term follow-up study to clarify the clinical significance of pvCTC status is warranted.
    The Annals of thoracic surgery 07/2009; 87(6):1669-75. · 3.74 Impact Factor
  • Article: Perivascular epithelioid cell tumor of the rib.
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    ABSTRACT: We present a rare case of perivascular epithelioid cell tumor (PEComa) in the right 6th rib of a 28-year-old man. A plain computed tomography scan showed a round osteolytic lesion in the right 6th rib. The resected tissue contained a globular-shaped, soft tumor. Histologically, the tumor was rich in vasculature and exclusively composed of perivascular epithelioid cells with clear cytoplasm. Immunohistochemically, the tumor expressed diffusely a melanocyte marker, human melanoma black-45, and focally a myogenic marker, alpha-smooth muscle actin, but not an epithelial marker, AE1/AE3. Fontana-Masson-positive melanin pigments were present and c-kit receptor tyrosine kinase (CD117), involved in the development of melanocytes but not myogenic cells, was expressed in tumor cells. These findings indicate that the tumor is PEComa with some differentiation into melanocytes. Notably, owing to the unique location of the occurrence, the tumor occupied bone marrow tissues of the rib, resulting that the tumor has the potential for hematogenous metastasis. In spite of the lack of cells with severe atypia, necrosis, and numerous mitoses, tumor cells invaded into surrounding tissues and overexpressed cyclin D1. To the best of our knowledge, this is the first case report of PEComa arising from the rib with the signs of malignant potential.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 07/2008; 452(6):697-702. · 2.49 Impact Factor
  • Article: Pulmonary lymphangiectasis in an asymptomatic adult.
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    ABSTRACT: Pulmonary lymphangiectasis is a rare anomaly in infancy that is characterized by dilatation of pulmonary lymphatic vessels resulting in fetal respiratory distress. Pulmonary lymphangiectasis is considered to occur exclusively in young children and neonates, and very few survive beyond an early age. We herein present an asymptomatic adult case of localized pulmonary lymphangiectasis with multiple nodules. A 27-year-old asymptomatic female presented with multiple nodules on chest computed tomogram images. An exploratory video-assisted thoracoscopy revealed multiple yellowish cysts on the visceral pleura, which were histologically diagnosed as lymphangiectasis. In the present study, the pathogenesis and clinical characteristics are discussed.
    Respiration 02/2006; 73(1):114-6. · 2.26 Impact Factor
  • Article: Long-term pulmonary function after lobectomy for primary lung cancer.
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    ABSTRACT: The aim of this study was to investigate the factors affecting long-term postoperative pulmonary function with a view to increasing the application of combined resection, bronchoplasty, and induction therapy. Results in 80 patients who underwent lobectomy for primary lung cancer were analyzed. Predicted postoperative pulmonary function was calculated using the formula: postoperative predicted function=preoperative function x[1-(b-n)/(42-n)], where n and b are the numbers of obstructed segments and total segments, respectively, in the resected lobe. Spirometry was performed serially on the preoperative day, and at 3, 6, 12, 18, and 24 months postoperatively. The difference between the predicted postoperative pulmonary function and the function measured at 12 months postoperatively was calculated, and clinical and therapeutic variables were analyzed. Univariate analysis revealed that the difference in vital capacity was significantly related to surgical approach, bronchoplasty, and induction therapy, while the difference in forced expiratory volume in one second (FEV1) correlated with surgical approach and induction therapy. Multiple regression analysis showed induction therapy to be the sole factor related to the differences in both vital capacity and FEV1. Lung resection after induction therapy may cause an additional loss of pulmonary function in the late phase.
    Asian cardiovascular & thoracic annals 01/2006; 13(4):311-5.
  • Article: Surgical results for chronic empyema using omental pedicled flap: long-term follow-up study.
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    ABSTRACT: Successful treatment of chronic empyema remains a challenge for thoracic surgeons. Herein, we report our 17 years of experience with the omental pedicled flap procedure for management of chronic empyema secondary to pulmonary tuberculosis. We retrospectively reviewed the surgical results of 23 patients who underwent surgical treatment for chronic empyema using an omental pedicled flap from 1987 to 2003. The subjects were 20 men and 3 women (mean age, 58.1 years) with average % vital capacity (VC) and forced expiratory volume in 1 second (FEV1) values of 48.1% and 1.19 L, respectively. Sixteen patients (69.6%) had bronchopleural fistulas and 21 (91.3%) were associated with infection by causative organisms (6 Aspergillus organisms, 4 methicillin-resistant Staphylococcus aureus, 10 others). An open window thoracostomy preceded in 17 patients (72.9%). Eleven patients were treated using an omental pedicled flap with or without a muscle flap, and 12 were treated using an omental pedicled flap with a partial thoracoplasty. There was 1 operation-related death, and clinical success was achieved in 19 patients (82.6%), in whom pulmonary function did not decrease significantly. During long-term follow-up, 5 patients died of respiratory failure, and their mean postoperative %VC and FEV1 values were 30.1% and 0.76 L, respectively. We concluded that the use of an omental pedicled flap for chronic empyema was effective even in cases with active infection, and did not compromise pulmonary function. Further, an additional thoracoplasty may completely obliterate the dead space, although indications should be referenced to preoperative pulmonary function.
    The Annals of thoracic surgery 07/2005; 79(6):1857-61. · 3.74 Impact Factor
  • Article: Thymic carcinoma with a large cystic lesion.
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    ABSTRACT: A 59-year-old man presented with a large anterior mediastinal mass. A computed tomography (CT) and magnetic resonance imaging showed a well-circumscribed cystic mass, 12 cm in size adjacent to the heart border and superior vena cava (SVC). A CT guided needle biopsy was performed, and instead of detecting malignant tissues but finding that gray muddy fluid was suctioned, suggesting cystic teratoma. At surgery, the tumor was confirmed advanced thymic carcinoma with pleural dissemination, then the tumor was extirpated with resection of SVC, followed by 2 cycles of chemotherapy. Histologically, the cystic wall was lined with malignant cells. We herein present a diagnostic pitfall case of thymic carcinoma having a large cystic component with which rare association should be recognized.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 01/2005; 52(12):574-6.
  • Article: Pulmonary benign metastasizing leiomyoma from the uterus in a postmenopausal woman: report of a case.
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    ABSTRACT: We report a case of pulmonary benign metastasizing leiomyoma (BML) from the uterus in a 77-year-old woman. The patient presented for investigation of multiple pulmonary nodules on a routine chest roentgenogram. Because a preoperative diagnosis could not be made, the largest tumor, 3.5 cm in diameter, was resected from the right lower lobe, and histological examination confirmed BML. She had undergone hysterectomy with oophorectomy for uterine leiomyomas 12 years earlier, at the age of 65. The microscopic findings of the lung tumor were similar to those of the uterine leiomyoma, and both lesions were histologically benign. Although this disease is considered to be hormone-dependent, metastasis was found in this elderly postmenopausal woman whose tumor was negative for estrogen receptor.
    Surgery Today 02/2004; 34(1):55-7. · 1.22 Impact Factor
  • Article: Bronchoscopically undiagnosed small peripheral lung tumors.
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    ABSTRACT: Small peripheral lung cancers (2 cm or less maximum diameter) are often surgically resected, and the survival rate of those patients has been reported to be significantly higher than that of patients with tumors 2.1 cm or more in diameter. We evaluated the status of these small tumors diagnosed during surgery, following unsuccessful transbronchial biopsy procedures. In a retrospective study, 84 consecutive patients, with a maximum diameter of 2 cm or less on chest computed tomography, were enrolled. All underwent surgery for diagnosis. Video-assisted thoracoscopic surgery was performed in 49 cases (58%), Video-assisted thoracoscopic surgery+mini-thoracotomy in ten cases (12%), and an open lung biopsy in 25 cases (30%). Primary lung cancer was found in 40 cases (48%), metastatic lung tumors in three cases (3%), and benign lung tumors in 41 cases (49%). Among the 40 primary lung cancer cases, adenocarcinoma was in 38, squamous cell carcinoma was in one, and small cell carcinoma was in one. The rate of stage IA was 90%. Surgical excision of undiagnosed small peripheral nodules without waiting is necessary if transbronchial biopsy diagnosis is unsuccessful, because of the high rate of stage IA non-small cell lung cancer.
    Interactive cardiovascular and thoracic surgery 01/2004; 2(4):517-20.
  • Article: Localized pleural malignant mesothelioma.
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    ABSTRACT: The occurrence of pleural malignant mesothelioma (MM) is unusual and the cases that appear as a localized tumor are extremely rare. A case of localized pleural MM including immunohistochemical findings is presented. A 70-year-old man had an abnormal shadow found during a routine roentgenogram at an annual health checkup and was admitted to Toneyama National Hospital (Toyonaka, Osaka, Japan) for detailed examinations. Chest X-rays showed a 2 x 5 cm-sized nodule with relatively smooth margins in the right segment three. Computed tomography (CT) showed an extrapleural mass with a smooth surface and a thickened parietal pleura, and results of a biopsy performed under CT scanning yielded MM. Systematic examinations did not show any metastasis and the patient underwent surgery for removal of the mass. The resected tumor, measuring 3.2 x 3.1 cm, was firm, partially encapsulated, and irregularly shaped. Pathological examinations revealed that it consisted of large polygonal cells, partially showing myxoid patterns, which led to a diagnosis of localized pleural MM. Tumor recurrence was seen, and the duration between initial symptoms and death was 29 months. This case suggests that localized pleural MM has a high proliferative potential and aggressive course, and is considered an early stage of diffuse pleural MM.
    Pathology International 10/2003; 53(9):616-21. · 1.62 Impact Factor
  • Article: Desmoplastic malignant mesothelioma: two cases and a literature review.
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    ABSTRACT: We present two cases of desmoplastic malignant mesothelioma (DMM) with pathological, immunohistochemical, and ultrastructural features. Each patient showed rapid progress and died within 1 year from appearance of the initial symptoms. Macroscopically, both showed a thickened pleura replaced by a tumor that encased the lung. Microscopic results of each showed that the tumors consisted of a dense fibrous area, with mild nuclear irregularities and hyperchromatism. In case 1, the tumor had invaded the diaphragm, chest wall, and cardiac sac; the mass in case 2 invaded the lung and diaphragm, and distal metastases were seen in the thoracic vertebrae, meninges, and liver. Ultrastructural findings in case 1 showed a few short blunt microvilli on the cell surfaces. DMM is occasionally difficult to distinguish from fibrous pleurisy and solitary fibrous tumor. Immunohistochemical examinations of the present cases showed the expression of cytokeratin and vimentin, and focal positive stainings of antihuman mesothelial cell antibody (HBME-1) in both, whereas CD34 and bcl2 were negative. Solitary fibrous tumor was excluded. Therefore, pathological, ultrastructural, and immunohistochemical findings led us a diagnosis of DMM in each case. The Ki-67 labeling index (Ki-67 LI) of cases 1 and 2 was 25.5 and 15.5, respectively, both high, which suggested malignancy. Widespread immunohistological panels of malignant mesothelioma were not evaluated; Immunohistological markers commonly used for the diagnosis of malignant mesothelioma were not evaluated; however, the high ki-67 LI results and positive HBME-1 staining were helpful factors for the diagnoses of DMM.
    Medical Electron Microscopy 10/2003; 36(3):173-8.
  • Article: Immunohistochemical analysis of resected clinical stage I pulmonary adenocarcinomas with high preoperative levels of serum carcinoembryonic antigen.
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    ABSTRACT: Clinical stage I pulmonary adenocarcinoma (AD) patients with persistently high serum carcinoembryonic antigen (CEA) levels after surgery have a poor prognosis. Although CEA staining pattern is reported to be a prognostic indicator for patients with colorectal cancer, the relationship with lung cancer is unclear. One hundred eighteen patients with clinical stage I AD underwent surgery from 1993 to 1997. Of them, 19 (16%) patients with a high preoperative serum level of CEA and 19 randomly selected control patients with preoperatively normal CEA were studied. CEA staining of tumor specimens from each of the 38 patients was performed, and the staining patterns were then classified into two types: apical and diffuse. Patients with normal postoperative serum CEA levels (group HN, n = 13) had a 5-year survival rate higher than those with persistently high postoperative serum CEA (group HH, n = 6). In a comparison between the two groups, apical patterns (n = 10) were only seen in group HN, and those who demonstrated an apical CEA staining pattern had a 5-year survival rate (5-YSR) of 80% as compared with 13% for those HN patients with only a diffuse pattern (p = 0.01). In the control group, 16 (84%) patients had an apical staining pattern and the other 3 patients showed no staining. Patients with normalized serum CEA levels had a high chance of showing an apical staining pattern, which may be a very good prognosis predictor for patients with high preoperative levels of CEA.
    The Annals of Thoracic Surgery 08/2003; 76(1):203-7. · 3.74 Impact Factor