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Uematsu M, Nakajima H, Miyake H, Wakabayashi M, Funasaka C, Kondoh C, Harano K, Matsubara N, Hosono A, Naito Y, Sakamoto N, Kojima M, Onishi T, Ishii G, Mukohara T. Digitally quantified area of residual tumor after neoadjuvant chemotherapy in HER2-positive breast cancer. Breast Cancer 2025:10.1007/s12282-025-01694-7. [PMID: 40172786 DOI: 10.1007/s12282-025-01694-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2025] [Accepted: 03/17/2025] [Indexed: 04/04/2025]
Abstract
BACKGROUND The area of residual tumor (ART) is a quantitative method for assessing tumors after neoadjuvant chemotherapy (NAC). This study evaluated whether ART can identify a favorable prognosis group in patients with HER2-positive surgically resected breast cancer and residual tumors post-NAC. METHODS We retrospectively reviewed patients with HER2-positive who underwent surgery after NAC, including trastuzumab, from 2005 to 2022 at our institution. ART was assessed at the maximum cut surface of the residual primary tumor using digital pathology images. Receiver operating characteristic curve analysis determined ART-Low and ART-High cutoffs, excluding ART-0 (0 mm2) patients. RESULTS Of the 219 patients, 82 had ART greater than 0 mm2. The median follow-up was 90.2 months. The number of patients in the ART-0, ART-Low (0 < ART ≤ 4.0 mm2), and ART-High (> 4.0 mm2) groups were 137, 39, and 43, respectively. The ART-Low group showed significantly shorter event-free survival compared to the ART-0 group (HR 3.50, 95% CI 1.52-8.06), and the ART-High group also tended toward poorer prognosis (HR 2.31, 95% CI 0.89-5.97). However, there was no significant difference in prognosis between the ART-Low and ART-High groups. CONCLUSIONS The current study suggests that even minimal residual tumor cells in the primary site can significantly impact on prognosis in HER2-positive early breast cancer.
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Affiliation(s)
- Mao Uematsu
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Bunkyō, Japan
| | - Hiromichi Nakajima
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan.
- Department of Experimental Therapeutics, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan.
- Department of General Internal Medicine, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan.
| | - Hirohiko Miyake
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Masashi Wakabayashi
- Biostatistics Division, Center for Research Administration and Support, National Cancer Center, Chuo-Ku, Japan
| | - Chikako Funasaka
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Department of Experimental Therapeutics, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Chihiro Kondoh
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Kenichi Harano
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Department of Experimental Therapeutics, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Nobuaki Matsubara
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Ako Hosono
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Department of Pediatric Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Yoichi Naito
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Department of Experimental Therapeutics, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Department of General Internal Medicine, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Naoya Sakamoto
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Exploratory Oncology Research and Clinical Trial Center, Division of Pathology, Chuo-Ku, Japan
| | - Motohiro Kojima
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Tatsuya Onishi
- Department of Breast Surgery, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Genichiro Ishii
- Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Bunkyō, Japan
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
| | - Toru Mukohara
- Department of Medical Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, 277-8577, Japan
- Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Bunkyō, Japan
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Nagata H, Kinoshita T, Sakashita S, Kojima M, Taki T, Kuwata T, Yura M, Shitara K, Ishii G, Sakamoto N. Area of Residual Tumor Measurement After Preoperative Chemotherapy as an Objective and Quantitative Method for Predicting the Prognosis of Gastric Cancer: A Single-Center Retrospective Study. World J Surg 2025; 49:717-726. [PMID: 39810214 DOI: 10.1002/wjs.12482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2024] [Revised: 11/29/2024] [Accepted: 12/29/2024] [Indexed: 01/16/2025]
Abstract
BACKGROUND Pathological regression grade after chemotherapy evaluated by surgically resected specimens is closely related with prognosis. Since usefulness of measuring the area of the residual tumor (ART) has been reported, this study aimed to evaluate the utility of ART in predicting the prognosis of patients with gastric cancer (GC) who received preoperative chemotherapy. METHODS This single-center retrospective study examined the relationship between ART and survival outcomes. We included 92 patients who underwent preoperative chemotherapy followed by radical surgery for GC. Digital images were used to measure the ART in the largest pathological slice of each patient's surgical tumor specimen. We simply subclassified the patients as either ART-0 (< 0.1 mm2 or carcinoma in situ) or non-ART-0 to compare the prognoses. RESULTS Significant differences were noted in overall survival and recurrence-free survival (RFS) between ART-0 (n = 19) and non-ART-0 (n = 73). The survival curves were similar to those of major pathological response (MPR) (n = 24) or non-MPR (n = 68), which are commonly used as surrogate endpoint presently. Multivariate analysis revealed ART and ypN independent prognostic factors for RFS. Survival curves stratified using ART and ypN to indicate risk grades (low-, moderate-, or high-) were not significantly different from those stratified using the other three existing pathological regression grade systems and ypN. CONCLUSION ART-based pathological assessment is a simple and useful method for predicting the prognosis in patients with GC who underwent radical surgery after chemotherapy.
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Affiliation(s)
- Hiromi Nagata
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
- Division of Gastric Surgery, National Cancer Center Hospital East, Kashiwa, Japan
- Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takahiro Kinoshita
- Division of Gastric Surgery, National Cancer Center Hospital East, Kashiwa, Japan
| | - Shingo Sakashita
- Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Japan
| | - Motohiro Kojima
- Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Japan
| | - Tetsuro Taki
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
| | - Takeshi Kuwata
- Department of Genetic Medicine and Services, National Cancer Center Hospital East, Kashiwa, Japan
| | - Masahiro Yura
- Division of Gastric Surgery, National Cancer Center Hospital East, Kashiwa, Japan
| | - Kohei Shitara
- Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Japan
| | - Genichiro Ishii
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
- Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Naoya Sakamoto
- Division of Pathology, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, Kashiwa, Japan
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Li W, Chang Y, Bai X, Cao H. Comparison of the effectiveness of neoadjuvant chemotherapy and adjuvant chemotherapy for improving prognosis in triple-negative breast cancer patients. Am J Transl Res 2024; 16:3978-3989. [PMID: 39262758 PMCID: PMC11384378 DOI: 10.62347/vhme8736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 07/12/2024] [Indexed: 09/13/2024]
Abstract
OBJECTIVE To compare the effectiveness of surgery combined with neoadjuvant chemotherapy and radiotherapy (SNCR) versus surgery combined with adjuvant chemotherapy and radiotherapy (SACR) in improving the prognosis of triple-negative breast cancer (TNBC) patients. METHODS Clinical data from 112 TNBC patients treated between January 2014 and February 2019 were retrospectively collected. Data included clinical characteristics and 5-year disease-free survival (DFS). Kaplan-Meier (K-M) survival curves were used to analyze the associations of various factors with DFS. Lasso-Cox regression was used to screen significant variables identified by K-M survival analysis. Multivariate Cox regression was used to determine independent prognostic factors affecting DFS. RESULTS K-M survival analysis showed that treatment regimen (P=0.012), TNM (tumor, node, metastasis) staging (P=0.049), N staging (P=0.015), P53 (P=0.015), KI-67 (P=0.002), neutrophil-to-lymphocyte ratio (NLR) (P<0.001), platelet-to-lymphocyte ratio (PLR) (P<0.001), and cancer antigen 153 (CA153) (P<0.001) were associated with DFS in TNBC patients. Lasso-Cox regression analysis identified treatment regimen, TNM stage, P53, KI-67, NLR, PLR, and CA153 as features related to DFS when λ=0.053741 (1se). Multivariate Cox regression analysis revealed that treatment regimen (P<0.001, 95% CI: 2.309-14.396, HR=5.765), P53 (P=0.010, 95% CI: 1.315-7.864, HR=3.216), and NLR (P=0.001, 95% CI: 2.098-14.553, HR=5.525) were independent prognostic factors affecting DFS. A nomogram model was constructed, and time-dependent receiver operating characteristic (ROC) curve analysis showed that the model's areas under the curve (AUC) for predicting 1-, 3-, and 5-year DFS were 0.928, 0.816, and 0.665, respectively. CONCLUSION The SNCR regimen significantly improves DFS in patients with stage IIb to IIIa TNBC compared to the traditional SACR regimen.
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Affiliation(s)
- Wangbin Li
- Department of Oncology and Radiotherapy, Yulin Hospital, The First Affiliated Hospital of Xi'an Jiaotong University Yulin 719000, Shaanxi, China
| | - Yuwei Chang
- Department of Oncology and Radiotherapy, Yulin Hospital, The First Affiliated Hospital of Xi'an Jiaotong University Yulin 719000, Shaanxi, China
| | - Xiaohui Bai
- Department of Oncology and Radiotherapy, Yulin Hospital, The First Affiliated Hospital of Xi'an Jiaotong University Yulin 719000, Shaanxi, China
| | - Hongxin Cao
- Department of Oncology and Radiotherapy, Yulin Hospital, The First Affiliated Hospital of Xi'an Jiaotong University Yulin 719000, Shaanxi, China
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Fisher TB, Saini G, Rekha TS, Krishnamurthy J, Bhattarai S, Callagy G, Webber M, Janssen EAM, Kong J, Aneja R. Digital image analysis and machine learning-assisted prediction of neoadjuvant chemotherapy response in triple-negative breast cancer. Breast Cancer Res 2024; 26:12. [PMID: 38238771 PMCID: PMC10797728 DOI: 10.1186/s13058-023-01752-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 12/11/2023] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND Pathological complete response (pCR) is associated with favorable prognosis in patients with triple-negative breast cancer (TNBC). However, only 30-40% of TNBC patients treated with neoadjuvant chemotherapy (NAC) show pCR, while the remaining 60-70% show residual disease (RD). The role of the tumor microenvironment in NAC response in patients with TNBC remains unclear. In this study, we developed a machine learning-based two-step pipeline to distinguish between various histological components in hematoxylin and eosin (H&E)-stained whole slide images (WSIs) of TNBC tissue biopsies and to identify histological features that can predict NAC response. METHODS H&E-stained WSIs of treatment-naïve biopsies from 85 patients (51 with pCR and 34 with RD) of the model development cohort and 79 patients (41 with pCR and 38 with RD) of the validation cohort were separated through a stratified eightfold cross-validation strategy for the first step and leave-one-out cross-validation strategy for the second step. A tile-level histology label prediction pipeline and four machine-learning classifiers were used to analyze 468,043 tiles of WSIs. The best-trained classifier used 55 texture features from each tile to produce a probability profile during testing. The predicted histology classes were used to generate a histology classification map of the spatial distributions of different tissue regions. A patient-level NAC response prediction pipeline was trained with features derived from paired histology classification maps. The top graph-based features capturing the relevant spatial information across the different histological classes were provided to the radial basis function kernel support vector machine (rbfSVM) classifier for NAC treatment response prediction. RESULTS The tile-level prediction pipeline achieved 86.72% accuracy for histology class classification, while the patient-level pipeline achieved 83.53% NAC response (pCR vs. RD) prediction accuracy of the model development cohort. The model was validated with an independent cohort with tile histology validation accuracy of 83.59% and NAC prediction accuracy of 81.01%. The histological class pairs with the strongest NAC response predictive ability were tumor and tumor tumor-infiltrating lymphocytes for pCR and microvessel density and polyploid giant cancer cells for RD. CONCLUSION Our machine learning pipeline can robustly identify clinically relevant histological classes that predict NAC response in TNBC patients and may help guide patient selection for NAC treatment.
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Affiliation(s)
- Timothy B Fisher
- Department of Biology, Georgia State University, Atlanta, GA, 30302, USA
| | - Geetanjali Saini
- School of Health Professions, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - T S Rekha
- JSSAHER (JSS Academy of Higher Education and Research) Medical College, Mysuru, Karnataka, India
| | - Jayashree Krishnamurthy
- JSSAHER (JSS Academy of Higher Education and Research) Medical College, Mysuru, Karnataka, India
| | - Shristi Bhattarai
- School of Health Professions, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Grace Callagy
- Discipline of Pathology, University of Galway, Galway, Ireland
| | - Mark Webber
- Discipline of Pathology, University of Galway, Galway, Ireland
| | - Emiel A M Janssen
- Department of Pathology, Stavanger University Hospital, Stavanger, Norway
- Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, Stavanger, Norway
| | - Jun Kong
- Department of Mathematics and Statistics, Georgia State University, Atlanta, GA, 30303, USA.
| | - Ritu Aneja
- Department of Biology, Georgia State University, Atlanta, GA, 30302, USA.
- School of Health Professions, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
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Fisher TB, Saini G, Ts R, Krishnamurthy J, Bhattarai S, Callagy G, Webber M, Janssen EAM, Kong J, Aneja R. Digital image analysis and machine learning-assisted prediction of neoadjuvant chemotherapy response in triple-negative breast cancer. RESEARCH SQUARE 2023:rs.3.rs-3243195. [PMID: 37645881 PMCID: PMC10462230 DOI: 10.21203/rs.3.rs-3243195/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Background Pathological complete response (pCR) is associated with favorable prognosis in patients with triple-negative breast cancer (TNBC). However, only 30-40% of TNBC patients treated with neoadjuvant chemotherapy (NAC) show pCR, while the remaining 60-70% show residual disease (RD). The role of the tumor microenvironment (TME) in NAC response in patients with TNBC remains unclear. In this study, we developed a machine learning-based two-step pipeline to distinguish between various histological components in hematoxylin and eosin (H&E)-stained whole slide images (WSIs) of TNBC tissue biopsies and to identify histological features that can predict NAC response. Methods H&E-stained WSIs of treatment-naïve biopsies from 85 patients (51 with pCR and 34 with RD) were separated through a stratified 8-fold cross validation strategy for the first step and leave one out cross validation strategy for the second step. A tile-level histology label prediction pipeline and four machine learning classifiers were used to analyze 468,043 tiles of WSIs. The best-trained classifier used 55 texture features from each tile to produce a probability profile during testing. The predicted histology classes were used to generate a histology classification map of the spatial distributions of different tissue regions. A patient-level NAC response prediction pipeline was trained with features derived from paired histology classification maps. The top graph-based features capturing the relevant spatial information across the different histological classes were provided to the radial basis function kernel support vector machine (rbfSVM) classifier for NAC treatment response prediction. Results The tile-level prediction pipeline achieved 86.72% accuracy for histology class classification, while the patient-level pipeline achieved 83.53% NAC response (pCR vs. RD) prediction accuracy. The histological class pairs with the strongest NAC response predictive ability were tumor and tumor tumor-infiltrating lymphocytes for pCR and microvessel density and polyploid giant cancer cells for RD. Conclusion Our machine learning pipeline can robustly identify clinically relevant histological classes that predict NAC response in TNBC patients and may help guide patient selection for NAC treatment.
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Affiliation(s)
| | | | - Rekha Ts
- JSSAHER (JSS Academy of Higher Education and Research) Medical College
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Adachi M, Aoyama N, Kojima M, Sakamoto N, Miyazaki S, Taki T, Watanabe R, Matsuura K, Kotani D, Kojima T, Fujita T, Tabuchi K, Ishii G, Sakashita S. The area of residual tumor predicts esophageal squamous cell carcinoma prognosis following neoadjuvant chemotherapy. J Cancer Res Clin Oncol 2023; 149:4663-4673. [PMID: 36201027 DOI: 10.1007/s00432-022-04366-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/16/2022] [Indexed: 10/10/2022]
Abstract
PURPOSE To clarify the utility of the area of residual tumor for patients with esophageal squamous cell cancer treated with neoadjuvant chemotherapy. METHODS We enrolled 186 patients with esophageal squamous cell cancer who underwent surgical resection following neoadjuvant chemotherapy at our hospital. Using digital images, we measured the area of residual tumor at the maximum plane of the specimen and divided the patient into three groups as follows: 0 (area = 0 mm2), low (area = 0-40 mm2), and high (area ≥ 40 mm2). The clinicopathological factors and prognosis were compared among these groups. RESULTS The median area of the residual tumor was 15.0 mm2 (range 0-1,448.8 mm2). Compared with the 0 and low group, the high group was significantly associated with poorer recurrence-free survival (all P < .001) and overall survival (P < .001 [vs. 0] and P = .017 [vs low]). The area of residual tumor, ypN, tumor regression grade, and lymphovascular invasion were independent predictors of recurrence-free survival. By dividing the patients using a combination of the area of residual tumor and lymphovascular invasion, the high and/or lymphovascular invasion ( +) group displayed significantly poor recurrence-free survival than the 0 group and low/lymphovascular invasion ( -) group. However, there was no significant difference in the recurrence-free survival between the 0 group and low/lymphovascular invasion ( -) group. CONCLUSION The area of residual tumor is a promising histopathological prognostic factor for patients with esophageal squamous cell cancer treated with neoadjuvant chemotherapy. Moreover, it is a possible candidate histopathological factor for postoperative chemotherapy selection.
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Affiliation(s)
- Masahiro Adachi
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
- Department of Otolaryngology, Head and Neck Surgery, University of Tsukuba, Tsukuba, Japan
| | - Naoki Aoyama
- Department of Gastroenterology and Endoscopy, National Cancer Center Hospital East, Kashiwa, Japan
- Department of Gastroenterology and Hepatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Motohiro Kojima
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
- Division of Pathology, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan
| | - Naoya Sakamoto
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
- Division of Pathology, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan
| | - Saori Miyazaki
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
| | - Tetsuro Taki
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
| | - Reiko Watanabe
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
| | - Kazuto Matsuura
- Department of Head and Neck Surgery, National Cancer Center Hospital East, Kashiwa, Japan
| | - Daisuke Kotani
- Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Japan
| | - Takashi Kojima
- Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Japan
| | - Takeo Fujita
- Department of Esophageal Surgery, National Cancer Center Hospital East, Kashiwa, Japan
| | - Keiji Tabuchi
- Department of Otolaryngology, Head and Neck Surgery, University of Tsukuba, Tsukuba, Japan
| | - Genichiro Ishii
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan
| | - Shingo Sakashita
- Department of Pathology and Clinical Laboratories, National Cancer Center Hospital East, Kashiwa, Japan.
- Division of Pathology, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 6-5-1, Kashiwanoha, Kashiwa, Chiba, 277-8577, Japan.
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