Sachio Maehara
Tokyo Medical University
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Featured researches published by Sachio Maehara.
Clinical Cancer Research | 2010
Jitsuo Usuda; Shuji Ichinose; Taichirou Ishizumi; Hiroki Hayashi; Keishi Ohtani; Sachio Maehara; Shoutarou Ono; Hidetoshi Honda; Naohiro Kajiwara; Osamu Uchida; Hidemitsu Tsutsui; Tatsuo Ohira; Harubumi Kato; Norihiko Ikeda
Purpose: Most centrally located early lung cancers (CLELC) <1.0 cm in diameter do not invade beyond the bronchial cartilage, and photodynamic therapy (PDT) with Photofrin is currently recommended as a treatment option for such lesions. NPe6 is a second-generation photosensitizer, and because it has a longer absorption band (664 nm) than Photofrin (630 nm), we hypothesized that NPe6-PDT would exert a strong antitumor effect against cancer lesions >1.0 cm in diameter, which are assumed to involve extracartilaginous invasion and to be unsuitable for treatment with Photofrin-PDT. Experimental Design: Between June 2004 and December 2008, 75 patients (91 lesions) with CLELC underwent NPe6-PDT after the extent of their tumors had been assessed by fluorescence bronchoscopy for photodynamic diagnosis and tumor depth had been assessed by optical coherence tomography. Results: Seventy cancer lesions ≤1.0 cm in diameter and 21 lesions >1.0 cm in diameter were identified, and the complete response rate was 94.0% (66 of 70) and 90.4% (19 of 21), respectively. After the mass of large tumors and deeply invasive tumors had been reduced by electrocautery, NPe6-PDT was capable of destroying the residual cancer lesions. Conclusion: NPe6-PDT has a strong antitumor effect against CLELCs >1.0 cm in diameter that have invaded beyond the bronchial cartilage, thereby enabling the destruction of residual cancer lesions after mass reduction of large nodular- or polypoid-type lung cancers by electrocautery. The PDT guidelines for lung cancers should therefore be revised because use of NPe6-PDT will enable expansion of the clinical indications for PDT. Clin Cancer Res; 16(7); 2198–204. ©2010 AACR.
Journal of Thoracic Oncology | 2010
Jitsuo Usuda; Shuji Ichinose; Taichirou Ishizumi; Hiroki Hayashi; Keishi Ohtani; Sachio Maehara; Shoutarou Ono; Naohiro Kajiwara; Osamu Uchida; Hidemitsu Tsutsui; Tatsuo Ohira; Harubumi Kato; Norihiko Ikeda
Background: Patients with centrally located early lung cancer (CLELC) are often heavy smokers with a considerably high risk of multiple primary lung cancer (MPLC) lesions; treatment strategies for such patients must preserve the cardiopulmonary function. Methods: Between July 2004 and July 2008, patients with CLELC underwent photodynamic therapy (PDT) using NPe6, second-generation photosensitizer at Tokyo Medical University Hospital. Among these patients, we retrospectively analyzed MPLC, which was treated by surgery plus PDT or PDT alone and examined the effectiveness of PDT, and we propose a treatment strategy for patients with MPLC. Results: A total of 64 patients with CLECL received NPe6-PDT, and MPLCs were found in 22 patients (34.4%) using sputum cytology and a bronchoscopical examination using autofluorescence bronchoscopy. Among these 22 patients, 10 patients underwent surgery for primary lung cancer and underwent NPe6-PDT for the treatment of secondary primary CLELC, one patient underwent PDT for CLELC as a primary lesion followed by an operation for peripheral-type lung cancer as a secondary primary lesion, and 11 patients underwent PDT alone for MPLC lesions (28 lesions) that were roentgenographically occult lung cancers. Among these 22 patients with MPLC including peripheral-type lung cancers, which were resected by surgery, all 39 CLELC lesions exhibited a complete response after PDT, and all patients were alive. Conclusions: For patients with lung cancer with a long-term history of smoking, careful follow-up examinations after surgical resection are needed considering the incidence of metachronous primary lung cancers. PDT can play an important role for the treatment strategy for MPLC.
Lung Cancer | 2010
Jitsuo Usuda; Yoshihiko Tsunoda; Shuji Ichinose; Taichirou Ishizumi; Keishi Ohtani; Sachio Maehara; Shoutarou Ono; Hidemitsu Tsutsui; Tatsuo Ohira; Tetsuya Okunaka; Kinya Furukawa; Yoshikazu Sugimoto; Harubumi Kato; Norihiko Ikeda
The ATP-binding cassette (ABC) transporter protein, BCRP (breast cancer resistance protein)/ABCG2 pumps out some types of photosensitizers used in photodynamic therapy (PDT) and causes resistance to the antitumor effect of PDT. The purpose of this study was to investigate the association between the expression of BCRP and the efficacy of PDT using Photofrin, or the second-generation photosensitizer, NPe6, for centrally located early lung cancers. Using human epidermoid carcinoma cells, A431 cells and the BCRP-overexpressing A431/BCRP cells, we examined the effects of BCRP expression on the effect of PDT by cell viability assay in vitro, and investigated the expression of BCRP by immunohistochemical analysis in 81 tumor samples obtained from patients with centrally located early lung cancers. The A431/BCRP cells were more resistant to Photofrin-PDT than A431 cells in vitro, and Fumitremorgin C, a specific inhibitor of BCRP, reversed the resistance. However, there was no significant difference in the antitumor effect of NPe6-PDT between these cells. All of the 81 centrally located early lung cancer lesions were BCRP-positive (2+, 45 lesions; 1+, 30 lesions) and all the patients were male and heavy smokers (>30 pack-years). The expression of BCRP significantly affected the efficacy of Photofrin-PDT in cancer lesions > or =10mm in diameter (P=0.04). On the other hand, NPe6-PDT exhibited a strong antitumor effect, regardless of the expression status of BCRP. Photofrin may be a substrate of BCRP and be pumped out from the cells, therefore, BCRP may be a molecular determinant of the outcome of Photofrin-PDT.
Lung Cancer | 2015
Yoshihisa Shimada; Hisashi Saji; Keishi Otani; Sachio Maehara; Junichi Maeda; Koichi Yoshida; Yasufumi Kato; Masaru Hagiwara; Masatoshi Kakihana; Naohiro Kajiwara; Tatsuo Ohira; Soichi Akata; Norihiko Ikeda
OBJECTIVES We reviewed the medical record of a series of patients with synchronous multiple lung cancers (SMLC), in an attempt to identify the optimal treatment strategy for multiple ground-glass opacities (GGOs). MATERIALS AND METHODS From 2004 to 2010, 1223 patients underwent complete resection of non-small cell lung cancer. Among these, there were 67 patients (5.5%) with SMLC with at least 1 of the nodules showing GGO appearance. SMLC was divided into the main cancer (MC) which was a main target based on its tumor size or radiological invasiveness and sub-nodules. According to consolidation/tumor ratio (CTR) on thin-section computed tomography, 67 cases were classified into GG-group (MC showing GGO-dominant lesion; CTR≤0.5) and GS-group (MC showing solid-dominant lesion; CTR>0.5). RESULTS There were 24 patients in the GG-group (36%) and 43 patients in the GS-group (64%). Surgical resections included 11 sublobar resections (SLs), 32 lobectomies, 19 lobectomy+SLs, and 4 bilobectomies. There were 39 patients with a total of 118 unresected GGOs after the initial surgery. Among them, the frequency of growth was 8% on a per-nodule basis with the median tumor doubling time of 1373 days, and new GGOs emerged in 15 patients (23%). Multivariate analysis demonstrated that larger size of MC and the GS-group was associated with poor prognosis, whereas growth of the residual GGOs, the development of new GGOs, or whether or not all GGOs were treated did not affect survival. The 5-year OS proportions were 95.8% for the GG-group and 68.0% for the GS-group (p=0.009), and 92.4% for a MC of ≤25 mm and 53.6% for a MC of >25 mm (p=0.008). CONCLUSION Survival of patients with multifocal GGOs is strongly affected by radiological findings of the MC. Strict surgical control for MC could be most important.
Lung Cancer | 2018
Hideyuki Furumoto; Yoshihisa Shimada; Kentaro Imai; Sachio Maehara; Junichi Maeda; Masaru Hagiwara; Tetsuya Okano; Ryuhei Masuno; Masatoshi Kakihana; Naohiro Kajiwara; Tatsuo Ohira; Norihiko Ikeda
OBJECTIVES The aim of this study was to conduct comparative analyses of the biological malignant potential of clinical stage IA adenocarcinoma using positron emission tomography/computed tomography (PET/CT), high-resolution CT (HRCT), and three-dimensional CT (3DCT). The predictive performance of these parameters was evaluated in terms of clinical outcomes and pathological invasiveness (positive lymphatic permeation, blood-vessel invasion, pleural invasion, and lymph-node metastasis). MATERIALS AND METHODS We enrolled 170 patients with c-IA adenocarcinoma who underwent PET/CT, HRCT, and 3D reconstruction of lung structures using the Synapse Vincent system (Fujifilm Corporation, Tokyo, Japan) followed by complete resection. Maximum standardized uptake values (SUVmax) of F18-fluorodeoxyglucose and the size and volume of the solid part of the tumor were quantified and analyzed in relation to surgical outcomes. RESULTS Univariate analysis demonstrated that all the three parameters and whole-tumor volume were associated with unfavorable disease-free survival (DFS), while the volume of the solid part was the independent predictor on multivariate analysis (p < .001). The receiver operating characteristic curves for pathological invasiveness, determined using the variables dichotomized at each cut-off level (SUVmax 2.4; solid-part size 1.23 cm; solid-part volume 779 mm3), showed that all were significantly correlated with pathological invasiveness and prognosis, whereas the combination of SUVmax and the solid-part volume was the most powerful predictor of survival and pathological invasiveness compared to any other parameters: the 4-year DFS and proportion of pathological invasiveness in patients with SUVmax > 2.4 and solid-part volume > 779 mm3 versus those with SUVmax ≤ 2.4 or solid-part volume ≤779 mm3 were 81.2% versus 98.3% (p < .001) and 84.3% versus 15.1% (p < .001), respectively. CONCLUSION In c-IA adenocarcinoma, the volume of the solid part of the tumor was the independent predictor for unfavorable DFS, and the integration of the volume of the solid part and SUVmax was highly beneficial for the prediction of survival and pathological invasiveness.
International Journal of Oncology | 2015
Sachio Maehara; Jitsuo Usuda; Taichiro Ishizumi; Shuji Ichinose; Keishi Ohtani; Tatsuya Inoue; Kentaro Imai; Hideyuki Furumoto; Yujin Kudo; Naohiro Kajiwara; Tatsuya Ohira; Norihiko Ikeda
To identify a possible new treatment modality for malignant pleural mesothelioma (MPM), we examined whether combination treatment consisting of pemetrexed chemotherapy and photodynamic therapy (PDT) using the photosensitizer NPe6, enhanced the antitumor effect in both in vitro and in vivo models. We also investigated preclinical treatment schedules. Four human malignant mesothelioma cell lines (MSTO‑211H, H2052, H2452 and H28) were assayed using the WST assay after treatment with pemetrexed and NPe6‑PDT. The treatment schedule for the combination treatment was examined using nude mice. Pemetrexed pre‑treatment enhanced the lethal effect of NPe6‑PDT in the four malignant mesothelioma cell lines, but NPe6‑PDT followed by pemetrexed treatment did not enhance cell lethality in the in vitro assay. Pemetrexed pre‑treatment did not enhance the intracellular accumulation of NPe6, which is one of the determinants of the antitumor effect of PDT. In nude mice injected with MSTO‑211H cells and then treated using a combination of pemetrexed and NPe6‑PDT (10 mg/kg NPe6, 10 J/cm(2) laser irradiation), the tumor volume decreased by 50% but subsequently increased, reaching the pre‑treatment value after 14 days. Pemetrexed treatment followed by NPe6‑PDT resulted in an 80% reduction in the tumor size and inhibited re‑growth. NPe6‑PDT followed by pemetrexed treatment resulted in a 60% reduction in tumor size but did not inhibit re‑growth. NPe6‑PDT induced the expression of thymidylate synthase (TS), which confers resistance to pemetrexed, and NPe6‑PDT followed by pemetrexed treatment did not enhance the treatment outcome in vivo. In conclusion, combination treatment, consisting of pemetrexed followed by NPe6‑PDT, should be further investigated as a new treatment modality for MPM. In the future, this combination treatment may contribute to a reduction in local recurrence and a prolonged survival period in patients with MPM.
Lasers in Surgery and Medicine | 2011
Jitsuo Usuda; Shuji Ichinose; Taichirou Ishizumi; Keishi Ohtani; Tatsuya Inoue; Sachio Maehara; Kentarou Imai; Kiyoteru Shima; Tatsuo Ohira; Harubumi Kato; Norihiko Ikeda
PDT induces apoptosis, inflammatory reactions, immune reactions, and damage to the microvasculature around the tumors. The mechanisms responsible for the anticancer effects of Photofrin‐PDT and NPe6‐PDT differ somewhat. To select a photosensitizer for lung cancer treatment and to improve the efficacy of PDT, the mechanisms of action for PDT using Photofrin or NPe6 must be elucidated and the phenomena validated by analyzing molecular determinants from clinical samples.
Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXVII 2018 | 2018
Keishi Ohtani; Jitsu Usuda; Emiyu Ogawa; Sachio Maehara; Kentaro Imai; Tatsuya Inoue; Masaru Hagiwara; Masatoshi Kakihana; Naohiro Kajiwara; Tatsuo Ohira; Tsunenori Arai; Norihiko Ikeda
Background: Skin photosensitivity is a major side effect of photodynamic therapy (PDT). It is induced by the photosensitizer remaining in the skin. It is usually rapidly metabolized by the liver, but the pharmacokinetic profile varies widely among individuals. This makes it difficult to predict the incidence of skin photosensitivity. Therefore, we conducted a prospective study to investigate whether the NPe6 fluorescence intensity in skin after NPe6-PDT could be measured safely in human patients using a fluorescence sensing system for judging the risk of skin photosensitivity. Methods: The NPe6 fluorescence measurements using a constructed fluorescence sensing system at the inside of the arm were acquired prior to and 5 and 10 minutes after NPe6 administration as well as at the time of PDT (4-5 hours after administration), at discharge (2 or 3 days after PDT), and at 1 or 2 weeks after PDT. Participants were interviewed as to whether they had any complications at 2 weeks after PDT. Results: Nine male patients and one female patient entered this study. All of the measurements of NPe6 fluorescence in the skin could be obtained without any complications. The spectral peak was detected at the time of discharge (2-3 days after administration) in most cases and it decreased at 1 or 2 weeks after PDT. Conclusions: The fluorescence of NPe6 in the skin could be detected feasibly using the fluorescence sensing system in human patients. Measuring fluorescence intensity in the skin might be useful to predict the incidence of skin photosensitivity after PDT.
Journal of Thoracic Oncology | 2018
Masatoshi Kakihana; Masaru Hagiwara; Junichi Maeda; Yoshihisa Shimada; Sachio Maehara; Naohiro Kajiwara; Tatsuo Ohira; Norihiko Ikeda
uniformity, and variant call accuracy from FFPE TNA and DNA. For example, a single pool of 8 RNA and 16 DNA libraries yielded >500,000 reads for each library, with RNA fusions called with 189 to 11,274 reads and DNA mutations detected down to 5% variant allele frequency. Variant calls were 100% concordant with independent results and included mutations in EGFR, RAS, PIK3CA, and BRAF, along with fusions in ALK, RET, and NRG1 and skipped METex14. Conclusion: The co-detection strategy generated reliable quantitative information from low-input tumor FFPE DNA and TNA within three days. The simplicity and speed of the approach, coupled with a standardized workflow, has the potential to increase the accessibility of NGS analysis and accelerate the return of results for NSCLC patients.
Journal of Thoracic Disease | 2018
Naohiro Kajiwara; Sachio Maehara; Junichi Maeda; Masaru Hagiwara; Tetsuya Okano; Masatoshi Kakihana; Tatsuo Ohira; Norihiko Kawate; Norihiko Ikeda
Background In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors. Methods We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases. Results Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely. Conclusions Preoperative simulation using virtual navigation bronchial intervention reduces the surgeons stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments are helpful for bronchial intervention procedures, and are also excellent devices for educational training.