Hiroshi Izumi

Juntendo University, Edo, Tōkyō, Japan

Are you Hiroshi Izumi?

Claim your profile

Publications (44)61.31 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Cotyledonoid dissecting leiomyoma (Sternberg tumor) is a rare variant of the uterine smooth muscle tumor. Although this tumor is a benign tumor clinically and pathologically, the appearance and growth pattern is unusual, so it may be misdiagnosed as malignancy.
    Archives of Gynecology and Obstetrics 08/2014; 291(2). DOI:10.1007/s00404-014-3406-2 · 1.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chondroid chordoma (CC) is a rare but commonest subtype of chordoma with little reported clinical information. The present study summarizes and updates present knowledge of CC.
    Clinical Neuroradiology 07/2014; 24(4). DOI:10.1007/s00062-014-0321-7 · 1.62 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A 67-year-old woman sensed a slowly growing, painless hard mass in the left parietal region. Cranial computed tomography showed focal bony erosion and homogeneous sclerotic change at the affected site. Magnetic resonance (MR) imaging revealed an enhanced subcutaneous mass and irregularly thickened dura mater. Intraoperatively, the subcutaneous tumor was found to be strongly adhered to the temporalis muscle. The outer table was eroded adjacent to the subcutaneous tumor, whereas the bony structures of the inner table were intact. The dura mater underneath had irregular-shaped, yellowish convolutions both on the outer and inner surfaces. The patient underwent total tumor resection with sufficient normal margins. The histological diagnosis was World Health Organization (WHO) grade I meningioma, with finger-like outward extensions through the dura mater and overlying skull, and infiltration among into the temporalis muscle fibers. Meningiomas may form a subcutaneous mass without intracranial growth.
    Neurologia medico-chirurgica 09/2013; 53(10). DOI:10.2176/nmc.cr2012-0324 · 0.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ovarian carcinoma has been difficult to diagnose at an early stage. Recently, it has been recognized that the measurement of blood N-ERC/mesothelin levels aids early detection in and postoperative therapeutic monitoring of patients with mesothelioma, who have been exposed to asbestos. ERC/mesothelin has also been reported to be expressed in ovarian carcinoma. We determined serum N-ERC/mesothelin levels in patients with ovarian carcinoma using an enzyme-linked immunosorbent assay (ELISA). In addition, we immunohistochemically evaluated surgically resected specimens for C-ERC/mesothelin expression. As a result, of the 32 patients with ovarian tumors (18 carcinoma, 2 borderline tumors), one patient with serous adenocarcinoma showed increased N-ERC/ mesothelin levels. Immunohistochemically, of the 20 ovarian tumor (carcinoma and borderline tumor) specimens evaluated for serum N-ERC/mesothelin, 9 (45.0%) were positive for C-ERC/mesothelin. The C-ERC/mesothelin-positive specimens were found to be serous and clear cell adenocarcinomas. If serum N-ERC/mesothelin, which is considered useful for early detection in and therapeutic monitoring of patients with mesothelioma, may also be used for ovarian carcinoma monitoring, it may be a valuable serum tumor marker for the early detection of ovarian carcinoma.
    Oncology letters 10/2012; 4(4):637-641. DOI:10.3892/ol.2012.796 · 0.99 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Gene methylation leads to malignant progression in some tumors. The mechanism by which mesothelin is expressed in malignant mesothelioma (MM) is not well understood. MM is histologically divided into 3 subtypes, that is, the epithelioid, sarcomatoid, and biphasic types, and it was shown that mesothelin expression was restricted to the epithelioid type and the epithelioid component of the biphasic type of MM. However, its regulatory mechanism of expression has not been clarified. Here, we studied the expression of mesothelin by immunohistochemistry along with the methylation status of 20 CpG sites in the promoter of the mesothelin gene (MSLN) in 118 lung specimens, including 39 MM, 41 lung carcinoma, 26 nonneoplastic pulmonary lesions, and 12 normal lung tissue samples by the methylation-sensitive single nucleotide primer extension technique. We confirmed that mesothelin was expressed in the epithelioid type and epithelioid component of the biphasic type of MM but neither in the sarcomatoid type nor sarcomatous component of the biphasic type. Surprisingly, the MSLN promoter was significantly hypomethylated in the MM cases regardless of its subtype, compared with the other pulmonary lesions and normal lung tissue samples. These findings suggested that hypomethylation of the MSLN promoter may be specifically associated with the formation of MM, regardless of its expression status, and that the expression of mesothelin protein was lost in the sarcomatoid type by some unknown posttranscriptional regulatory mechanism. We also identified 4 CpG sites, among the 20 sites studied, to be more specifically hypomethylated in MM cases.
    Human pathology 09/2010; 41(9):1330-8. DOI:10.1016/j.humpath.2010.03.002 · 2.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A 61-year-old man presented with a rare pleural malignant mesothelioma of the spine manifesting as progressive weakness of the bilateral lower extremities, numbness in the body and both legs, and dysfunction of the bladder and bowel. He had previous occupational exposure to asbestos while working at a car repair shop and had undergone right panpleuropneumonectomy under a diagnosis of sarcomatous type mesothelioma in the right pleural space. Magnetic resonance imaging of the spine with gadolinium showed an enhanced intramedullary tumor at the T4 level. Operative findings disclosed the clouded and swollen right posterior nerve root, and the pial surface was covered by clouded arachnoid-like membrane. The removed part of the T4 posterior nerve root and intramedullary tumor revealed malignant mesothelioma with invasion spreading along the posterior nerve root. He died of respiratory failure 3 months after the diagnosis. This case shows that spinal metastasis must be considered if a patient with pleural malignant mesothelioma shows neurological worsening and neuroimaging shows an abnormal lesion in the thoracic spinal cord. However, the patient's neurological condition is very difficult to improve in the presence of spinal cord infiltration.
    Neurologia medico-chirurgica 05/2009; 49(4):167-71. DOI:10.2176/nmc.49.167 · 0.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The patient was 54-year-old woman diagnosed as recurrent invasive thymoma (type B3; WHO classification). Although partial response was obtained by systemic chemotherapy (PAC: cisplatin, doxorubicin, cyclophosphamide), the tumor started to become enlarged after cessation of chemotherapy. Combined treatment of octreotide and prednisolone was administrated because various chemotherapies, including PAC, were not effective. After seven months, the tumor size was markedly decreased. The combination of octreotide and prednisolone should be considered as one of the choices of treatment in patients with recurrent thymoma.
    Internal Medicine 02/2009; 48(12):1061-4. DOI:10.2169/internalmedicine.48.1922 · 0.97 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Because mesothelioma initially progresses on the surface of the pleura and peritoneum without forming masses, it has been difficult to diagnose at an early stage. It would be very useful to identify a tumor marker that could be used for screening to enable more diagnoses to be made at an early, treatable stage. We had previously identified N-ERC/mesothelin as a potential biomarker for mesothelioma. In the current work, we used a newly developed ELISA system to gain data on N-ERC/mesothelin levels in various clinical settings. A total of 102 healthy volunteers were recruited. In addition, 39 patients were diagnosed with mesothelioma, 53 patients were diagnosed with diseases that should be distinguished from mesothelioma, and 201 subjects were diagnosed with asbestos-related nonmalignant diseases (including simple exposure to asbestosis) who were treated at any of the cooperating hospitals were enrolled. Serum N-ERC/mesothelin levels measured by a new ELISA system showed that the median values from patients with mesothelioma were extremely high compared with levels obtained from other patients. Analysis in terms of histologic type showed that serum levels of N-ERC/mesothelin were elevated in epithelioid type mesothelioma, especially. In four important models of clinical settings, the sensitivity and specificity of N-ERC/mesothelin were about 71% to 90% and 88% to 93%, respectively. N-ERC/mesothelin is a very promising tumor marker for mesothelioma, especially epithelioid mesothelioma.
    Clinical Cancer Research 04/2008; 14(5):1431-7. DOI:10.1158/1078-0432.CCR-07-1613 · 8.19 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report a case of thymic carcinoma associated with dermatomyositis (DM) in a 53-year-old man. The patient presented with the characteristic features of a skin rash with Gottron's papules, proximal muscle weakness, and increased serum levels of the muscle-associated enzymes. Comprehensive clinical examinations revealed an anterior mediastinal tumor. We resected the tumor and histological examination confirmed squamous cell carcinoma of the thymus. Thereafter, his clinical symptoms improved dramatically and his serum levels of muscle-associated enzymes dropped, indicating that the DM was a paraneoplastic phenomenon. Our search of the literature found only one other case report of DM accompanied by thymic carcinoma, and to our knowledge, this is the fi rst documented case of dramatic improvement of DM after resection of thymic carcinoma. We propose that thymic carcinoma should be added to the list of malignancies that can complicate DM as a paraneoplastic disease.
    Surgery Today 02/2008; 38(3):245-8. DOI:10.1007/s00595-007-3601-x · 1.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We tried to clarify whether the histologic subtypes and the size of the solid component of an adenocarcinoma are more important predictive factors for invasiveness or prognosis than is total tumor size, even in lung adenocarcinomas that were 2 cm or smaller. Between 1996 and December 2005, after standard surgical treatment, 82 patients were diagnosed as having adenocarcinoma with a maximum diameter of 2 cm or less. The group comprised 37 females and 45 males, with ages ranging from 41 to 80 years (median, 64). The clinicopathologic records of the patients were examined with regard to age, sex, nodal status, tumor size (largest diameter of the total tumor as well as the largest diameter without the bronchioloalveolar carcinoma [BAC] component [solid component]), serum carcinoembryonic antigen level, and histologic type. These variables were analyzed as risk factors for vascular or lymphatic invasion, lymph node metastasis, and prognosis. Histologic subtype was classified into two groups: mixed BAC (mixed adenocarcinoma with BAC) and minimal or non-BAC (tumors with little or no BAC component). Histologic subtype was a significant predictive factor both for invasiveness (vascular or lymph vessels) and lymph node metastasis, in both univariate and multivariate analysis. Tumor diameter was not a significant factor in either univariate or multivariate analysis (p = 0.28, 0.15, respectively). However, diameter excluding the BAC component was a significant factor for invasiveness in mixed BAC type (p = 0.035), whereas total diameter was not significant (p = 0.28). Finally, histologic subtype and lymph node metastasis were significant prognostic factors for survival in both univariate (p = 0.03, 0.05, respectively) and multivariate (p = 0.04, 0.05, respectively) analyses. The 5-year survival rate was 94.4% (94.1% for pN0) for the mixed BAC type and 71.4% (78.7% for pN0) for the minimal or non-BAC type (p = 0.009; p = 0.04 for pN0 nodes). Small adenocarcinomas can be classified into two categories. The first category is a minimal or non-BAC adenocarcinoma that shows aggressive biological behavior. The second category is a mixed BAC, which demonstrates less invasive or aggressive biological behavior than the minimal or non-BAC type, with the degree of invasiveness being associated with the size of the non-BAC component.
    The Annals of thoracic surgery 02/2007; 83(1):209-14. DOI:10.1016/j.athoracsur.2006.07.051 · 3.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Pulmonary lymphangioleiomyomatosis (LAM) is a rare and progressive disease of young women that usually causes death from respiratory failure. Here we report an early case that was diagnosed by thoracoscopy. A 28-year-old woman presented to a local clinic with chest pain and her chest X-ray film showed left pneumothorax. After placement of a chest tube, the lung re-expanded fully. Following the recurrence of left pneumothorax, she was referred to our hospital and underwent video-assisted thoracoscopic surgery (VATS). However, left pneumothorax recurred again one month later. She underwent a second thoracoscopic operation, during which a bulla was recognized in the lingular segment of the left lung and was resected. On histological examination of the surgical specimen findings consistent with LAM were obtained. Taking the preoperative imaging findings and the thoracoscopic findings into consideration, a diagnosis of early lymphangioleiomyomatosis was made. Thoracoscopic management of pneumothorax in young women can facilitate the early diagnosis of this condition.
    Annals of thoracic and cardiovascular surgery: official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 01/2006; 11(6):405-7. · 0.69 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rosai et al. published the World Health Organization (WHO) classification of thymic epithelial tumors in 1999, and its clinical usefulness seems to be established. It is our purpose to find the clinically relevant diagnostic points in the WHO Histological Classification of Thymoma. Thymomas surgically removed from 100 consecutive patients at Juntendo University Hospital between October 1983 and February 2002 were classified according to the WHO histological classification. We assessed overall survival and recurrence-free rate calculated for each tumor type in the WHO classification compared with those of tumors classified by the Masaoka system. The thymic epithelial tumors in this series comprised 10 type A, 15 type AB, 18 type B1, 21 type B2, 33 type B3, and 3 type C tumors according to the WHO classification. Based on the Masaoka system, the disease was stage I in 53 patients, stage II in 30, stage III in 15, and stage IV in 2. The 15-year recurrence-free rate was 100% for type A, AB and B1, while the rates for types B2 and B3 were 66.7% and 54.5%, respectively. The 10-year recurrence-free rate was 66.7% for type C. The 15-year recurrence-free rate of the 64 patients with type A, AB, B1, and B2 thymomas was significantly higher from that of the 33 patients with type B3 thymoma (p=0.0026). When using the WHO classification, it is critical to distinguish type B3 thymoma from other tumor types.
    Annals of thoracic and cardiovascular surgery: official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 01/2006; 11(6):367-73. · 0.69 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Diffuse pleural mesothelioma is a rare condition with a poor prognosis. Recent reports have indicated that extensive surgery combined with chemotherapy and radiotherapy prolongs the survival of selected patients with early disease. Thoracoscopy allows complete visualization of the pleural cavity and provides high-quality biopsy samples. We present a case of successful diagnosis of bilateral pleural mesothelioma by thoracoscopy. It is important to observe the contralateral pleural cavity by thoracoscopy to confirm the presence or absence of a tumor before considering extrapleural pneumonectomy for mesothelioma.
    Annals of thoracic and cardiovascular surgery: official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 09/2005; 11(4):252-5. · 0.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report here 4 cases of multilocular thymic cysts (MTCs) with reactive lymphoid follicular hyperplasia. They were admitted to our hospital to examine anterior mediastinal masses demonstrated on chest computed tomographic scans. Three patients presented high-grade intermittent fever, and 2 patients were associated with Sjogren syndrome with elevated serum antinuclear antibody levels. All patients were subjected to extended thymectomy. Interestingly, their fever disappeared immediately after surgery. Histologically, the lesions were characterized by several cystic spaces separated by various thick walls with dense lymphoid tissue containing large reactive germinal centers. The inner cyst walls were lined by flattened cuboidal epithelia in some portions. Columnar epithelia with focal cilia were partially observed in 2 cases. These pathological findings led to a diagnosis of MTCs that were thought to result from cystic transformation of medullary duct derivatives by acquired inflammatory processes. The pathological findings, together with clinical courses of our cases, suggest that inflammation accompanied by autoimmune diseases may play, in part, an important role in the development of MTCs.
    Human Pathlogy 08/2005; 36(7):841-4. DOI:10.1016/j.humpath.2005.05.004 · 2.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: It has been reported that small-sized invasive lung adenocarcinomas, i.e., those classified as type C through type F according to Noguchi's classification, may also recur even after complete resection. We evaluated the prognostic value of molecular biologic markers (apoptosis, Ki-67, p53, epidermal growth factor) and clinicopathological factors in patients with small-sized invasive lung adenocarcinomas. The clinical records of all patients who had had a peripheral adenocarcinoma surgically resected between 1996 and 2002, and histologically diagnosed as type C through type F according to Noguchi's classification were retrospectively reviewed. The apoptotic index (AI) was determined by the triphosphate biotin nick end-labeling method and the expression of Ki-67, aberrant p53 protein and epidermal growth factor receptor was determined by immunohistochemical staining. Data from 28 patients who had been followed up for a mean period of 41.8 months (range: 16 to 89 months) were evaluated. During the follow-up period, recurrence was seen in 6 patients. The log-rank test showed that AI was a significant predictor of cancer recurrence. The 5-year disease-free survival rate of the 10 patients in the high AI group (AI > 0.3%) was 100%; while that of the 18 patients in the low AI group (AI < or = 0.3%) was 50.5% (p = 0.036). None of the other molecular biologic markers or clinicopathological factors were found to be a significant predictor of cancer recurrence. Peripheral small-sized invasive lung adenocarcinomas with a low AI carry an increased risk of distant metastases, indicating that adjuvant chemotherapy after complete resection might be needed.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 07/2005; 53(7):345-53. DOI:10.1007/s11748-005-0048-0
  • Lung Cancer 07/2005; 49. DOI:10.1016/S0169-5002(05)81168-7 · 3.74 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Human papilloma virus (HPV) is the most important factor in the oncogenic mechanism of cervical tumor. Furthermore, in a separate multi-stage process, abnormality in cell cycle kinetics has been demonstrated. In order to elucidate the oncogenic mechanism, we examined the relationship between cervical carcinoma and HPV infection, and also investigated the expression of p53 and p21 proteins as well as the cell proliferation capability by detecting Ki-67, and analyzed the correlations of these factors. We studied the biopsy specimens from 107 patients of chronic cervicitis, cervical intraepithelial neoplasia and squamous cell carcinoma (SCC). HPV DNA was detected by the hybrid capture method. Immunostaining by LSAB procedures were performed using antibodies to p53 protein, p21 and MIB-1. The PCR-denaturing gradient gel electrophoresis (DGGE) method was used to search for mutation in exons 5, 6, 7 and 8 of p53. Of 107 cases studied, high-oncogenic HPV was detected in 80 cases (74.8%) with a particularly high prevalence in SCC. No correlation was observed between HPV infection and expression of p53, p21 or Ki-67. The degree of positivity of Ki-67 expression tended to be higher with disease progression. Cases strongly positive (2+) for p53 and p21 proteins were weakly positive for Ki-67, and cases positive (1+) or negative for p53 and p21 were strongly positive for Ki-67. In oncogenesis of cervical carcinoma, p53 protein, p21 protein and HPV may act separately as independent factors in some cases, and there is a strong possibility that other factors are involved.
    Rinsho byori. The Japanese journal of clinical pathology 07/2005; 53(6):494-8.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Many histologic classifications of thymic epithelial tumors have been reported to date, but to the authors' knowledge, none of them closely reflect the clinical behavior or prognosis of the tumor. Therefore, it is necessary to establish a biologic marker for thymic epithelial tumors. Variants of CD44 may be important in promoting tumor progression and metastasis. Accordingly, the expression of CD44 isoforms in thymic epithelial neoplasms was investigated using immunohistochemistry to assess their possible value as prognostic indicators. Expression of CD44v6 in thymic epithelial tumors was investigated with immunohistochemistry using consecutive surgical specimens resected from 108 patients between 1983 and 2002 at Juntendo University Hospital in Tokyo, Japan. Among the 108 thymic epithelial tumors, 70 were negative for CD44v6, 20 were weakly positive, and 18 were strongly positive. The status of CD44v6 expression (negative vs. weakly plus strongly positive) was found to be correlated with the tumor stage according to the Masaoka staging system (noninvasive vs. invasive tumors) (P = 0.0214). When patients with tumors that were negative and weakly positive for CD44v6 expression were combined, the 5-year, 10-year, and 15-year recurrence-free survival rates were 98.2%, 95.9%, and 86.1%, respectively, whereas the corresponding rates for patients with strongly positive tumors were 73.5%, 73.5%, and 55.1%, respectively. Therefore, these two groups demonstrated a significant difference with regard to recurrence-free survival (P = 0.0172). CD44v6 expression in thymic epithelial neoplasms demonstrated a significant difference based on the World Health Organization classification, the Masaoka stage (invasive vs. noninvasive tumors), and recurrence, if an appropriate cutoff value was chosen in each case. This suggests that CD44v6 can be used as a marker that reflects the stage of thymic tumors.
    Cancer 06/2005; 103(10):2015-22. DOI:10.1002/cncr.21046 · 4.90 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Primary thymic adenocarcinoma, mucinous subtype, is extremely rare with only one case reported to date. We describe herein a case of thymic mucinous adenocarcinoma. A 59-year-old man was identified to have an anterior mediastinal tumor and was diagnosed as mucinous adenocarcinoma. Clinical and radiographic examinations disclosed no evidence of tumor elsewhere. The patient received radiotherapy, but the general condition deteriorated and died 11 months after tumor detection. Thoracic autopsy revealed an anterior mediastinal tumor measuring greater than 10 cm, uncapsulated, and white. The tumor had clear margins and was clearly isolated from the lung. Histologically, the tumor demonstrated papillary, acinar, and cribriform structure and produced abundant extracellular mucin. Immunohistochemically, most tumor cells were positive for cytokeratin 7, were partially positive for CD5, and were negative for TTF-1, Sp-A, CDX-2, MUC2, napsin A, and cytokeratin 20. Collectively, the diagnosis of the tumor was primary mucinous adenocarcinoma of the thymus. We propose that the mucinous subtype should be recognized as one of the histopathological entities of thymic adenocarcinoma.
    Human Pathlogy 03/2005; 36(2):219-23. DOI:10.1016/j.humpath.2004.11.008 · 2.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine if the preoperative administration of tegafur and uracil (UFT) to patients with lung adenocarcinoma could induce apoptosis. We conducted a randomized prospective study on 30 patients with lung adenocarcinoma, divided into two groups of 15 patients each. One group received UFT 600 mg/day preoperatively for 7 consecutive days and a control group received no chemotherapy or radiotherapy. The apoptotic index (AI) was determined by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end-labeling (TUNEL) method. Expression of Ki-67 was examined by immunohistochemical staining. The concentration of 5-fluorouracil (5-FU) in tumor tissue was measured by chemical assay. The AI of lung adenocarcinoma cells increased significantly in the UFT-treated group but not in the control group. A significant positive correlation was seen between the AI and the 5-FU concentrations in the tumor tissue. The continuous oral administration of UFT for 7 days preoperatively resulted in enhanced apoptosis and a significant positive correlation between the AI and 5-FU concentrations in lung adenocarcinoma. Therefore, it may be possible to evaluate the effects of adjuvant chemotherapy based on the AI.
    Surgery Today 02/2004; 34(10):822-7. DOI:10.1007/s00595-004-2814-5 · 1.21 Impact Factor

Publication Stats

199 Citations
61.31 Total Impact Points


  • 1990–2014
    • Juntendo University
      • • Department of Human Pathology
      • • Department of General Thoracic Surgery
      • • Department of Pathology and Oncology
      • • Department of Medicine
      Edo, Tōkyō, Japan
  • 1998
    • The University of Tokyo
      • Department of Surgical Sciences
      Tokyo, Tokyo-to, Japan