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Featured researches published by Tsuneyo Takizawa.


The Journal of Thoracic and Cardiovascular Surgery | 1998

Lymph Node Metastasis In Small Peripheral Adenocarcinoma Of The Lung

Tsuneyo Takizawa; Masanori Terashima; Teruaki Koike; Takehiro Watanabe; Yuzo Kurita; Akira Yokoyama; Keiichi Honma

OBJECTIVE Our aim in this study is to clarify the clinical and pathologic features of small peripheral adenocarcinoma of the lung with special emphasis on intraoperative identification of lymph node metastasis. PATIENTS AND METHODS Between 1980 and 1996, 157 patients underwent lobectomy and complete hilar/mediastinal lymphadenectomy for small (1.1 to 2.0 cm in diameter) peripheral adenocarcinoma of the lung. The intraoperative assessment, the distribution of metastatic lymph nodes, and the association between the tumors histopathologic characteristics and lymph node metastasis were retrospectively investigated in this study. RESULTS Postoperative examination revealed lymph node metastasis in 27 (17%) patients. Lymph node metastases were not noticed during the operation in 19 of these 27 patients. Metastases were localized in single lymph nodes in 10 patients; the metastases were distributed over a segmental, a lobar, an interlobar, and a mediastinal lymph node. The prevalence of lymph node metastasis was as follows: Of 92 patients with well-differentiated adenocarcinoma, seven (8%) had lymph node metastases; of the 65 patients with other types of tumors, 20 (31%) had lymph node metastases. Of 120 patients without pleural involvement, 13 (11%) had lymph node metastases; of the 37 with pleural involvement, 14 (38%) had lymph node metastases. Five-year survivals were estimated at 91% +/- 6% (mean +/- 95% confidence interval) for 130 patients with N0 tumor and 30% +/- 22% for 27 patients with N1 or N2 tumor. CONCLUSIONS Intraoperative assessment is not reliable for identifying lymph node metastasis. Lobectomy and complete hilar/ mediastinal lymphadenectomy are necessary to determine N stage rigidly. Histologic degree of differentiation and pleural involvement are significantly associated with lymph node metastasis.


The Journal of Thoracic and Cardiovascular Surgery | 1998

Clinical analysis of small-sized peripheral lung cancer☆☆☆★★★

Teruaki Koike; Masanori Terashima; Tsuneyo Takizawa; Takehiro Watanabe; Yuzo Kurita; Akira Yokoyama

OBJECTIVE In Japan, with the initiation of the lung cancer screening program, small-sized peripheral lung cancer in which the diameter is 2 cm or less has been increasing. The purpose of this study is to determine the clinicopathologic behavior of small-sized lung cancer. METHODS Four hundred ninety-six patients with cT1 N0, peripheral, resected non-small-cell lung cancer, who were operated on between 1980 and 1996, were selected, grouped by tumor diameter or histologic type, and then analyzed for clinicopathologic behavior. On the basis of measured diameter roentgenographically, the patients were divided into two groups; group c-S with lesions 2 cm or less in diameter and group c-L with lesions 2.1 to 3 cm in diameter. RESULTS Lymph node metastasis was recognized in 18% of group c-S, in 23% of group c-L, and in 21% for the entire clinical group. The rate of those with the progressive state was 19% in group c-S and 26% in group c-L. The 5-year survival was 79.5% in group c-S and 69.3% in group c-L (i.e., there was a significant difference between the two groups). CONCLUSION Compared with the patients with lesions 2.1 to 3 cm in diameter, the patients with small-sized lung cancer had a milder progressive state and a better prognosis.


The Journal of Thoracic and Cardiovascular Surgery | 1997

Mediastinal lymph node metastasis in patients with clinical stage I peripheral non-small-cell lung cancer

Tsuneyo Takizawa; Masanori Terashima; Teruaki Koike; Hideki Akamatsu; Yuzo Kurita; Akira Yokoyama

Our aim in this study was to determine the mediastinal areas where lymphadenectomy should be done at the time of surgical resection of clinical stage I lung cancer. Between 1984 and 1994, 575 patients with clinical stage I non-small-cell lung cancer underwent lobectomy and systematic mediastinal lymphadenectomy. Mediastinal lymph nodes were pathologically positive for disease in 79 patients (14%), and positive nodes appeared normal intraoperatively in 54 patients (68%). Thirty-three percent of those patients with positive N2 (mediastinal) nodes had negative lobar (N1) nodes. In cancer of the right upper lobe, all N2 cases had the lymph node metastases in the superior mediastinal compartment. In cancer of the right middle lobe, all N2 cases but one had the metastases in subcarinal or anterior mediastinal nodes. In cancer of the right lower lobe, all N2 cases but one the metastases in subcarinal nodes. In cancer of the left upper lobe, all N2 cases had the lymph node metastases in the subaortic compartment. In cancer of the left lower lobe, all N2 cases but one had the lymph node metastases in the subcarinal area or subaortic compartment. In conclusion, systematic staging of mediastinal lymph nodes is necessary for all patients with resectable clinical stage I lung cancer. The location of the primary tumor determines the mediastinal areas where lymphadenectomy should be done to examine all lymph nodes.


The Journal of Thoracic and Cardiovascular Surgery | 1999

Pulmonary function after segmentectomy for small peripheral carcinoma of the lung

Tsuneyo Takizawa; Manabu Haga; Nobuo Yagi; Masanori Terashima; Hiroko Uehara; Akira Yokoyama; Yuzo Kurita

OBJECTIVE The aim of this study is to compare the pulmonary function after a segmentectomy with that after a lobectomy for small peripheral carcinoma of the lung. PATIENTS AND METHODS Between 1993 and 1996, segmentectomy and lobectomy were performed on 48 and 133 good-risk patients, respectively. Lymph node metastases were detected after the operation in 6 and 24 patients of the segmentectomy and lobectomy groups, respectively. For bias reduction in comparison with a nonrandomized control group, we paired 40 segmentectomy patients with 40 lobectomy patients using nearest available matching method on the estimated propensity score. RESULTS Twelve months after the operation, the segmentectomy and lobectomy groups had forced vital capacities of 2.67 +/- 0.73 L (mean +/- standard deviation) and 2.57 +/- 0.59 L, which were calculated to be 94.9% +/- 10.6% and 91.0% +/- 13.2% of the preoperative values (P =.14), respectively. The segmentectomy and lobectomy groups had postoperative 1-second forced expiratory volumes of 1.99 +/- 0.63 L and 1.95 +/- 0.49 L, which were calculated to be 93.3% +/- 10.3% and 87.3% +/- 14.0% of the preoperative values, respectively (P =.03). The multiple linear regression analysis showed that the alternative of segmentectomy or lobectomy was not a determinant for postoperative forced vital capacity but did affect postoperative 1-second forced expiratory volume. CONCLUSION Pulmonary function after a segmentectomy for a good-risk patient is slightly better than that after a lobectomy. However, segmentectomy should be still the surgical procedure for only poor-risk patients because of the difficulty in excluding patients with metastatic lymph nodes from the candidates for the procedure.


Lung Cancer | 1999

The influence of lung cancer mass screening on surgical results

Teruaki Koike; Masanori Terashima; Tsuneyo Takizawa; Manabu Haga; Yuzo Kurita; Akira Yokoyama; Hiroto Misawa

BACKGROUND After the introduction of the mass screening program for lung cancer, the number of patients detected by mass screening increased as well as the number of early staged patients. Therefore, we examined the influence of lung cancer mass screening on surgical results. METHODS A total of 1177 primary lung cancer cases, who underwent surgery from 1963 to 1992, were retrospectively reviewed. They were grouped according to the changes in the mass screening system: the first period (1963-1977) before lung cancer screening started, the second period (1978-1986) when mass screening was conducted by the local government, and the third period (1987-1992) after the launching of the national screening program. RESULTS The rate of cases detected by mass screening increased over time and the 5-year survival rate improved significantly, from 33.7% in the first period, to 51.8% in the second period and finally, to 58.4% in the third period. The improvement is attributable to a relative increase of rate of stage I cases and better stage I survival rate. Specifically, in stage I cases, improvement resulted from a relative increase of stage IA in peripheral type and roentgenographically occult lung cancer cases and from better survival rate of these two groups. CONCLUSION As lung cancer screening has come into widespread use, detection of peripheral small-sized lung cancer and roentgenographically occult lung cancer have increased and consequently, surgical results have improved.


The Annals of Thoracic Surgery | 1996

Staging of primary lung cancer by computed tomography-guided percutaneous needle cytology of mediastinal lymph nodes

Hideki Akamatsu; Masanori Terashima; Teruaki Koike; Tsuneyo Takizawa; Yuzo Kurita

BACKGROUND The necessity of an easy and noninvasive technique to evaluate mediastinal node status cytopathologically is considered. METHODS Eighteen cases of clinical N2 primary lung cancer were examined. Under local anesthesia, the lymph node was punctured with a 19-gauge needle using intermittent computed tomographic monitoring, and samples were studied cytologically. Subcarinal (no. 7) nodes and lower paratracheal (no. 4) nodes were sampled using the paraspinal posterior approach. Anterior mediastinal (no. 6) nodes were sampled using the parasternal anterior approach. Node status was diagnosed pathologically at operation. RESULTS Number 7 nodes were examined in 11 cases, no. 4 nodes in 5 cases, and no. 6 nodes in 2 cases. Malignant cells were detected in 14 cases. Fourteen cases were diagnosed as true positive, 2 cases as true negative, and 2 cases as false negative. The sensitivity, specificity, and accuracy of this method were 88%, 100%, and 89%, respectively. Pneumothorax developed in 4 cases (22%). CONCLUSIONS Computed tomography-guided percutaneous needle cytology of mediastinal lymph nodes is useful for staging primary lung cancer. Because this is a small series, additional studies are necessary.


The Annals of Thoracic Surgery | 2000

Surgical results for centrally-located early stage lung cancer

Teruaki Koike; Masanori Terashima; Tsuneyo Takizawa; Hiroko Tsukada; Akira Yokoyama; Yuzo Kurita; Keiichi Honma

BACKGROUND With the increasing use of mass screening programs for lung cancer, and especially the use of sputum cytology, the incidence of roentgenographically occult lung cancer has been increasing. These occult cancers comprise mainly histologically centrally-located early stage lung cancers. This study examined the clinicopathologic characteristics and surgical results of centrally-located early stage lung cancer. RESULTS From 1980 to 1998, there were 98 patients and 99 lesions of centrally-located early stage lung cancer resected. A total of 64 patients were detected by mass screening. Histologic examination revealed that 96 lesions were squamous cell carcinoma, and in these patients, there were 10 lesions of carcinoma in situ. The 5-year survival rate was 81.4% in all patients, and 88.9% in carcinoma in situ patients. In the postoperative follow-up period, a second lung cancer occurred in 13 patients. CONCLUSIONS The surgical results for centrally-located early lung cancer were good. However, sometimes these cancers are accompanied by a second centrally-located primary lung cancer, so it is necessary to follow-up with sputum cytology to allow early detection of additional centrally-located lung cancer.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2001

Vascular tumor in the mediastinum

Naoyuki Yoshino; Tsuneyo Takizawa; Teruaki Koike; Masanori Terashima; Keiichi Honma

Mediastinal venous hemangioma is a very rare neoplasm. Here, we describe our experience in treating a patient demonstrating such a tumor. The patient, a 23-year-old man, was admitted to our hospital because of a mediastinal cyst. A biopsy of the cystic wall was performed by Video-Assisted-Thoracic-Surgery, in April 1999. Clear serous fluid was found in the cyst, and it was thus incorrectly diagnosed to be a thymic cyst. The cyst continued to increase in size, and the patient began to show an increased temperature after being discharged. A resection of the tumor was performed in June 1999. The cyst was filled with bloody fluid and, according to the pathological analysis, was diagnosed to be a mediastinal venous hemangioma.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 1999

Results of surgery for primary lung cancer based on the new international staging system

Teruaki Koike; Masanori Terashima; Tsuneyo Takizawa; Tadashi Aoki; Takehiro Watanabe; Hideki Akamatsu

OBJECTIVES This study clarified the results of surgery for primary lung cancer based on the new international staging system. BACKGROUND On December 1997, the Japan Lung Cancer Society adopted a new TNM staging system which had already received international recognition. SUBJECTS AND METHODS The subjects of this study were 1062 consecutive previously untreated patients who underwent pulmonary resection for primary non-small cell lung cancer between January 1975 and December 1992. RESULTS The postoperative 5-year survival rate for all patients was 58.5%. Pathological staging demonstrated a survival rate which was 73.2% in stage I, 46.8% in stage II, 26.7% in stage III, and 20.0% in stage IV. In the staging subgroups, the survival rate was 79.6% in stage IA, 62.4% in stage IB, 62.2% in stage IIA, 42.0% in stage IIB, 26.9% in stage IIIA, and 26.3% in stage IIIB. Concerning the pm patients, the survival rate was 20.2% in pm1 and 20.0% in pm2, while the survival rate of the patients with N0 was 45.7% in pm1 and 40.0% in pm2. CONCLUSIONS A significant difference in the 5-year survival rate was recognized between the new stages IA and IB, and between the new stages IIA and IIB. When pm patients are diagnosed without lymph node metastasis, the opportunity for resection should not be lost.


Lung Cancer | 1998

A resected case of hilar type double primary lung cancer following endobronchial brachytherapy.

Teruaki Koike; Masanori Terashima; Tsuneyo Takizawa; Takehiro Watanabe; Mari Saito; Yuzo Kurita; Akira Yokoyama

A 61-year-old man with squamous cell carcinoma of the right B1 and the left second carina which extended to the left main bronchus, was treated with low dose rate brachytherapy bilaterally prior to resection. A complete response was gained at the right B1 and the left main bronchus, a resection of the left apical segment and the second carina was carried out with bronchoplastic procedures. The patient remains disease-free 2 years after the operation and maintains a good quality of life. In this case, the preoperative treatment with brachytherapy was effective.

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Hideki Akamatsu

Tokyo Medical and Dental University

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