Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Akira Iyoda is active.

Publication


Featured researches published by Akira Iyoda.


Thorax | 2003

High magnification bronchovideoscopy combined with narrow band imaging could detect capillary loops of angiogenic squamous dysplasia in heavy smokers at high risk for lung cancer

Kiyoshi Shibuya; H Hoshino; Masako Chiyo; Akira Iyoda; Shigetoshi Yoshida; Yasuo Sekine; Toshihiko Iizasa; Yukio Saitoh; Masayuki Baba; Kenzo Hiroshima; Hidemi Ohwada; Takehiko Fujisawa

Background: We investigated the use of high magnification bronchovideoscopy combined with narrow band imaging (NBI) for the detailed examination of angiogenic squamous dysplasia (ASD). This was carried out in relation to bronchial vascular patterns with abnormal mucosal fluorescence in heavy smokers at high risk for lung cancer. Methods: Forty eight patients with sputum cytology specimens suspicious or positive for malignancy were entered into the study. Conventional white light and fluorescence bronchoscopic examination was first performed. Observations by high magnification bronchovideoscopy with conventional white light were made primarily at sites of abnormal fluorescence, and then repeated with NBI light to examine microvascular networks in the bronchial mucosa. Spectral features on the RGB (Red/Green/Blue) sequential videoscope system were changed from the conventional RGB broadband filter to the new NBI filter. The wavelength ranges of the new NBI filter were B1: 400–430 nm, B2: 420–470 nm, and G: 560–590 nm. ASD tissues were also examined using a confocal laser scanning microscope equipped with argon-krypton (488 nm) and argon (514 nm) laser sources. Results: The microvessels, vascular networks of various grades, and dotted vessels in ASD tissues were clearly observed in NBI-B1 images. Diameters of the dotted vessels visible on NBI-B1 images agreed with the diameters of ASD capillary blood vessels diagnosed by pathological examination. Capillary blood vessels were also clearly visualised by green fluorescence by confocal laser scanning microscopy. There was a significant association between the frequency of dotted vessels by NBI-B1 imaging and tissues confirmed as ASD pathologically (p=0.002). Conclusions: High magnification bronchovideoscopy combined with NBI was useful in the detection of capillary blood vessels in ASD lesions at sites of abnormal fluorescence. This may enable the discrimination between ASD and another pre-invasive bronchial lesion.


Modern Pathology | 2006

Distinction of pulmonary large cell neuroendocrine carcinoma from small cell lung carcinoma: a morphological, immunohistochemical, and molecular analysis.

Kenzo Hiroshima; Akira Iyoda; Takashi Shida; Kiyoshi Shibuya; Toshihiko Iizasa; Hirohisa Kishi; Tohru Tanizawa; Takehiko Fujisawa; Yukio Nakatani

The distinction between pulmonary large cell neuroendocrine carcinoma and small cell carcinoma is difficult in some cases. Some propose that these carcinomas should be classified as one high-grade neuroendocrine carcinoma. We examined biological features of small cell carcinoma (n=23), large cell neuroendocrine carcinoma (n=17), and classic large cell carcinoma (n=12). The average ratio of nuclear diameter of the tumor cells to that of lymphocytes for small cell carcinoma was smaller than that for large cell neuroendocrine carcinoma (P<0.0001). The frequencies of the expressions of CD56, mASH1, TTF-1, and p16 were higher and that of NeuroD was lower in small cell carcinoma than in large cell neuroendocrine carcinoma. The frequency of loss of heterozygosity at 3p was higher in high-grade neuroendocrine carcinomas than in classic large cell carcinoma (P=0.0002). Allelic losses at D5S422 (5q33) were more frequent in small cell carcinoma than in large cell neuroendocrine carcinoma (P=0.0091). Mean fractional regional loss indices of the tumors were 0.38, 0.65, and 0.72 for patients with classic large cell carcinoma, large cell neuroendocrine carcinoma, and small cell carcinoma, respectively (P=0.0003). Five-year overall survivals of patients with classic large cell carcinoma, large cell neuroendocrine carcinoma and small cell carcinoma in stage I were 67, 73, 60%, respectively. Patients with NeuroD expression had better survivals, and those with p63 expression had poorer survivals in large cell neuroendocrine carcinoma. Patients with TTF-1 expression had poorer survivals in small cell carcinoma. Our data suggest that large cell neuroendocrine carcinoma and small cell carcinoma are different morphologically, phenotypically, and genetically, although there are some overlapping features. Although further studies are needed to analyze the biological behavior of high-grade neuroendocrine carcinomas including sensitivity to chemotherapy, the pathological distinction of large cell neuroendocrine carcinoma from small cell carcinoma may be necessary to treat the patients with neuroendocrine tumors.


The Journal of Thoracic and Cardiovascular Surgery | 2003

Impact of interstitial lung disease on surgical morbidity and mortality for lung cancer: analyses of short-term and long-term outcomes

Masako Chiyo; Yasuo Sekine; Takekazu Iwata; Koichiro Tatsumi; Kazuhiro Yasufuku; Akira Iyoda; Mizuto Otsuji; Shigetoshi Yoshida; Kiyoshi Shibuya; Toshihiko Iizasa; Yukio Saitoh; Takehiko Fujisawa

BACKGROUND This study investigated postoperative morbidity, mortality, and the long-term survival for patients with lung cancer who have interstitial lung diseases. METHODS A retrospective chart review of 931 patients with lung cancer who underwent pulmonary resection at Chiba University Hospital between 1990 and 2000 was undertaken. Interstitial lung disease was defined by medical history, physical examination, and abnormalities compatible with bilateral lung fibrosis on chest computed tomography or high-resolution computed tomography (36 patients: 3.9%, interstitial lung diseases group). The remaining 895 patients (96.1%) were categorized as non-interstitial lung disease group. RESULTS The incidence of postoperative pneumonia and acute or exacerbation of interstitial pneumonia was higher in the interstitial lung disease group (all P <.05). Thirty-day mortality was statistically equivalent between the interstitial lung disease and the non-interstitial lung disease groups (P =.30). The 5-year overall survivals were 62.5% (non-interstitial lung disease) and 35.6% (interstitial lung disease). Respiratory failure was the second main cause of death after the recurrence of primary cancer in the interstitial lung disease group. The risk factors for long-term mortality were interstitial lung diseases, advanced pathologic stage, male sex, high age, and positive smoking history (all P <.05). CONCLUSIONS Interstitial lung disease was a risk factor for developing postoperative morbidity and mortality and poor long-term survival due to the occurrence of respiratory failure.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2008

Role of endobronchial ultrasound-guided transbronchial needle aspiration in the management of lung cancer

Kazuhiro Yasufuku; Takahiro Nakajima; Taiki Fujiwara; Masako Chiyo; Akira Iyoda; Shigetoshi Yoshida; Makoto Suzuki; Yasuo Sekine; Kiyoshi Shibuya; Ichiro Yoshino

Endobronchial ultrasound (EBUS) is a promising new modality first introduced during the early 1990s. The radial probe EBUS was initially developed seeking for high-resolution imaging of processes in the airway wall and outside the airways. The structure of special importance was lymph nodes, walls of the central airways, and the mediastinum. After the development of miniaturized radial probes with flexible catheters having a balloon at the tip, it has been applied to aid bronchoscopists during biopsy of patients with respiratory diseases. In particular, the role of EBUS in transbronchial needle aspiration (TBNA) has been established. Radial probe EBUS-guided TBNA has increased the yield of TBNA of mediastinal lymph nodes, although it was still not a real-time procedure with target visualization. New convex probe EBUS (CP-EBUS) with the ability to perform real-time EBUS-guided TBNA (EBUS-TBNA) has emerged to overcome these problems. Indications for EBUS-TBNA are (1) lymph node staging in lung cancer patients; (2) diagnosis of intrapulmonary tumors; (3) diagnosis of unknown hilar and/or mediastinal lymphadenopathy; and (4) diagnosis of mediastinal tumors. Case series using EBUS-TBNA for mediastinal lymph node staging in lung cancer have reported a high yield, ranging from 89% to 98% (average 94.5%). To date, there are no reports of major complications related to EBUS-TBNA. EBUS-TBNA is a novel approach with a high diagnostic yield that is safe. The aim of this article was to review the current role of EBUS-TBNA for the management of lung cancer patients.


Thorax | 2008

Analysis of cell cycle-related proteins in mediastinal lymph nodes of patients with N2-NSCLC obtained by EBUS-TBNA: relevance to chemotherapy response

Sherif Mohamed; Kazuhiro Yasufuku; Takahiro Nakajima; Kenzo Hiroshima; Rieko Kubo; Akira Iyoda; Shigetoshi Yoshida; Makoto Suzuki; Yasuo Sekine; Kiyoshi Shibuya; Atef Farouk; Takehiko Fujisawa

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an accurate tool for lymph node staging of non-small cell lung cancer (NSCLC). Most patients with NSCLC require systemic chemotherapy during their treatment, with relatively poor responses. If the response to chemotherapy could be predicted, ideally at the time of the initial bronchoscopic examination, the therapeutic benefit could be maximised while limiting toxicity. A study was therefore undertaken to investigate the feasibility of EBUS-TBNA for obtaining tissue samples from mediastinal lymph nodes that can be used for immunohistochemical analysis, and to stratify patients with molecular-based pN2-NSCLC into chemo-responsive and chemoresistant subgroups who might benefit from tailoring of chemotherapy. Methods: The expression of six cell cycle-related proteins (pRb, cyclin D1, p16INK4A, p53, p21Waf1, Ki-67) in mediastinal lymph node specimens obtained by EBUS-TBNA was investigated by immunohistochemistry in 36 patients with pN2-NSCLC. Their predictive role(s) in the response to platinum-based chemotherapy was examined. Results: Immunostaining was feasible in all studied specimens. Univariate analysis revealed that p53 and p21Waf1 expressions were significantly related to the response to chemotherapy (p = 0.002 and p = 0.011, respectively). Multivariate logistic regression analysis revealed that only p53 overexpression was associated with a poor response to chemotherapy (p = 0.021). Conclusions: These results suggest that EBUS-TBNA is a feasible tool for obtaining mediastinal nodal tissue samples amenable for immunohistochemical analysis. Immunostaining of p53 in EBUS-TBNA-guided specimens may be useful in predicting the response to chemotherapy in patients with N2-NSCLC and helping in the selection of patients who might benefit from certain chemotherapeutic strategies.


The Annals of Thoracic Surgery | 2002

Pulmonary large cell carcinomas with neuroendocrine features are high-grade neuroendocrine tumors

Akira Iyoda; Kenzo Hiroshima; Masayuki Baba; Yukio Saitoh; Hidemi Ohwada; Takehiko Fujisawa

BACKGROUND In 1999, the World Health Organization (WHO) categorized large cell carcinoma with neuroendocrine features as variants of large cell carcinoma and reclassified neuroendocrine lung tumors, especially typical and atypical carcinoid tumors. However, to date, the clinical relationship between these categories of neuroendocrine lung tumors has not been clearly defined. METHODS We analyzed 133 cases of neuroendocrine tumors from primary lung carcinoma cases surgically resected. Using electron microscopy and immunohistochemical staining, we classified these cases as typical carcinoid (TC), atypical carcinoid (AC), large cell carcinoma with neuroendocrine features (LCNF), or small cell lung carcinoma (SCLC) based upon the WHO classification. RESULTS TC and AC tumors were not related to smoking (p < 0.001) and, unlike LCNF, were found in younger patients (p < 0.001) without a male predominance (p < 0.001). Multivariate analysis revealed that LCNF predicted poorer overall and disease-free survivals comparable with SCLC (overall survival, p = 0.019, hazards ratio, 6.34; disease-free survival, p = 0.007, hazards ratio, 8.19). CONCLUSIONS The prognoses of LCNF are comparable with those of SCLC, and LCNF should be classified as high-grade neuroendocrine tumors.


Clinical Cancer Research | 2004

Overexpression of Collagen XVIII Is Associated with Poor Outcome and Elevated Levels of Circulating Serum Endostatin in Non–Small Cell Lung Cancer

Toshihiko Iizasa; Hao Chang; Makoto Suzuki; Mizuto Otsuji; Sana Yokoi; Masako Chiyo; Shinichiro Motohashi; Kazuhiro Yasufuku; Yasuo Sekine; Akira Iyoda; Kiyoshi Shibuya; Kenzo Hiroshima; Takehiko Fujisawa

Purpose: The aim of this study was to determine whether collagen XVIII expression is correlated with circulating serum endostatin and whether this has any prognostic value in patients with non–small cell lung cancer (NSCLC). Experimental Design: Serum endostatin levels were measured quantitatively by a competitive enzyme immunoassay, and collagen XVIII expression in tumor tissue was investigated with an immunohistochemical method in a series of 94 patients who underwent surgery for NSCLC. Results: Sixty cases (63.8%) had positive immunohistochemical staining with anticollagen XVIII polyclonal antibodies, including strongly positive staining in 11 (11.7%) cases. The mean (± SD) serum endostatin level was 41.6 ± 34.4 ng/ml in the patient group and 16.3 ± 10.3 ng/ml in the control group (P < 0.0001). The 11 cases who were strongly collagen XVIII-positive had significantly higher serum endostatin levels than the cases who were negative or weakly positive (P = 0.0297). The 5-year survival rates of negative, weakly positive, and strongly positive patients were 77.8%, 56.9%, and 43.8%, respectively. The cases with strongly positive collagen XVIII expression had a significantly poorer outcome than cases with negative expression (P = 0.0027). A multivariate analysis with Cox proportional hazards model for disease-specific survival revealed that expression of collagen XVIII (strongly positive versus negative; weakly positive versus negative), tumor classification, and regional lymph node classification were independent prognostic factors. Conclusions: Our results suggest that expression of collagen XVIII in tumor tissue is strongly associated with a poorer outcome in NSCLC and correlates with elevated levels of circulating serum endostatin.


Pathology International | 2002

Alpha-fetoprotein-producing lung carcinoma: Report of three cases

Kenzo Hiroshima; Akira Iyoda; Tetsuya Toyozaki; Yukiko Haga; Masayuki Baba; Takehiko Fujisawa; Hiroshi Ishikura; Hidemi Ohwada

Three cases of alpha‐fetoprotein (AFP)‐producing lung carcinoma were studied histologically and immunohistochemically. Samples were obtained from two men and one woman who ranged in age from 64 to 71 years. Serum AFP levels for the three samples were 9826, 74.4 and 24.3 ng/mL. One case was classified as stage IIIA and two as stage IIIB. Two cases were diagnosed as large cell neuroendocrine carcinoma, and AFP expression was detected immunohistochemically. One of these samples showed differentiation to a hepatoid carcinoma, while the other was combined with a squamous cell carcinoma. The remaining case was a squamous cell carcinoma, and AFP was detected in only some of the tumor cells. All patients died within 2 years. The Ki‐67 labeling indices of the AFP‐producing pulmonary carcinomas (30.2 ± 4.6%) were significantly higher than those of AFP‐negative pulmonary carcinomas (P < 0.05). The high proliferative activity, advanced stage at presentation, vascular endothelial growth factor expression and vascular invasion observed in these tumors may explain the poor prognosis of AFP‐producing lung carcinomas.


The Journal of Thoracic and Cardiovascular Surgery | 2009

Postoperative recurrence and the role of adjuvant chemotherapy in patients with pulmonary large-cell neuroendocrine carcinoma

Akira Iyoda; Kenzo Hiroshima; Yasumitsu Moriya; Yasuo Iwadate; Yuichi Takiguchi; Takashi Uno; Yukio Nakatani; Ichiro Yoshino

OBJECTIVES The prognosis for patients with large-cell neuroendocrine carcinoma is generally very poor. In this study, we describe the clinical features of recurrent tumors of large-cell neuroendocrine carcinoma and discuss the role of adjuvant chemotherapy and management of recurrence in patients with large-cell neuroendocrine carcinoma. METHODS We retrospectively analyzed clinical data from 79 patients and evaluated the prognosis of patients with platinum-based adjuvant chemotherapy, recurrence patterns, patient response to chemotherapy or radiation therapy, and prognosis in patients who experienced relapse. RESULTS Of 72 patients, 36 had confirmed recurrent tumors upon follow-up examinations. Of those with recurrent tumors, 33 patients (91.7%) had their first recurrent tumors within 3 years. Patients who underwent platinum-based adjuvant chemotherapy had a significantly lower rate of tumor recurrence and a higher rate of disease-free survival than those who had non-platinum-based adjuvant chemotherapy or no adjuvant chemotherapy. Multivariate analyses revealed that platinum-based adjuvant chemotherapy, pathologic stage, and the presence of second cancer are independent prognostic factors. Three patients with limited resection of the primary tumor had poor prognosis with recurrence. Postoperatively, 11 of the 36 patients without recurrence (30.6%) had metachronous second primary cancers, of which 4 patients had more than 1 site. CONCLUSIONS Patients with large-cell neuroendocrine carcinoma had frequent recurrence following resection of the primary tumor, and those without recurrence often developed metachronous second primary cancers. Platinum-based adjuvant chemotherapy after surgery may be useful for preventing recurrence in patients with large-cell neuroendocrine carcinoma.


The Annals of Thoracic Surgery | 2011

Neoadjuvant and Adjuvant Chemotherapy in Resected Pulmonary Large Cell Neuroendocrine Carcinomas: A Single Institution Experience

Inderpal S. Sarkaria; Akira Iyoda; Mee Soo Roh; Gabriel L. Sica; Deborah Kuk; Camelia S. Sima; Maria Catherine Pietanza; Bernard J. Park; William D. Travis; Valerie W. Rusch

BACKGROUND Pulmonary large cell neuroendocrine carcinomas (LCNEC) are aggressive neoplasms with poor prognosis. The role of neoadjuvant and adjuvant therapies in these tumors remains uncertain. METHODS We performed a retrospective review of a prospective database. Kaplan-Meier estimates of overall survival (OS) were determined and compared across prognostic factors using log-rank analysis and the Cox proportional hazards model. RESULTS One hundred patients with resected LCNEC were identified from 1992 to 2008. Of these, 54% were male and 98% current or former smokers (mean 60.3 pack-years). Twenty-two patients received neoadjuvant platinum chemotherapy with a response rate of 68% (15 of 22). Eighty percent (80 of 100) underwent lobectomy and 11% (11 of 100) pneumonectomy with a 90% (90 of 100) complete resection (R0) rate. Seventy-one percent (71 of 100) were stage I-II, and 20 of 71 received platinum adjuvant chemotherapy. Mean OS was 40 months. Univariate factors associated with decreased OS included male gender (p = 0.007), increasing tumor (T) stage (p = 0.004), and stage III-IV disease (p = 0.04). Stage IB patients fared significantly worse than IA (p = 0.006). Multivariate analyses identified male gender (hazard ratio [HR] 2.3, p = 0.007), comorbid pulmonary disease (HR 2.3, p = 0.012), and pathologic stage (HR = 2.2, p = 0.011) as associated with risk of death. Univariate analysis in stage IB-IIIA completely resected (R0) patients receiving combination platinum-based induction and (or) adjuvant chemotherapy showed a trend toward improved OS (median survival 7.4 vs 2 years, p = 0.052). CONCLUSIONS The LCNEC has a high response rate to platinum-based neoadjuvant chemotherapy. Resected advanced-stage patients receiving combination neoadjuvant and (or) adjuvant chemotherapy may have a survival advantage. These therapies should be considered in resectable patients with LCNEC.

Collaboration


Dive into the Akira Iyoda's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge