Katsuo Yoshiya

Risk factor analysis of locoregional recurrence after sublobar resection in patients with clinical stage IA non-small cell lung cancer.

OBJECTIVE Although lobectomy is the standard surgical procedure for operable non-small cell lung cancer (NSCLC), sublobar resection also has been undertaken for various reasons. The aim of this study was to identify risk factors of locoregional recurrence and poor disease-specific survival in patients with clinical stage IA NSCLC undergoing sublobar resection. METHODS We retrospectively reviewed 328 patients with clinical stage IA NSCLC who underwent segmentectomy or wedge resection. Demographic, clinical, and pathologic factors were analyzed using the log-rank test as univariate analyses, and all factors were entered into a Cox proportional hazards regression model for multivariate analyses to identify independent predictors of locoregional recurrence and poor disease-specific survival. RESULTS The 5- and 10-year locoregional recurrence-free probabilities were 84.8% and 83.6%, respectively, and the 5- and 10-year disease-specific survivals were 83.6% and 73.6%, respectively. Four independent predictors of locoregional recurrence were identified: wedge resection (hazard ratio [HR], 5.787), microscopic positive surgical margin (HR, 3.888), visceral pleural invasion (HR, 2.272), and lymphatic permeation (HR, 3.824). Independent predictors of poor disease-specific survival were identified as follows: smoking status (Brinkman Index; HR, 1.001), wedge resection (HR, 3.183), microscopic positive surgical margin (HR, 3.211), visceral pleural invasion (HR, 2.553), and lymphatic permeation (HR, 3.223). All 4 predictors of locoregional recurrence also were identified as independent predictors of poor disease-specific survival. CONCLUSIONS Segmentectomy should be the surgical procedure of first choice in patients with clinical stage IA NSCLC who are being considered for sublobar resection. Patients having tumors presenting with no suspicious of pleural involvement would be suitable candidates for sublobar resection.

Efficacy and safety of extended thymectomy for elderly patients with myasthenia gravis

BACKGROUND The number of elderly patients who are diagnosed as myasthenia gravis (MG) is increasing in Japan. Although several factors affecting thymectomy have been well documented, few studies have focused on the efficacy and safety of thymectomy for elderly patients older than 60 years. METHODS We evaluated 94 patients with MG who underwent extended thymectomy, and divided them into two groups: patients younger than 59 years and patients older than 60 years. Preoperative patient data, pathology of the thymus, complications, and clinical outcome were evaluated. RESULTS In 69 young patients and 25 elderly patients, we observed no significant differences between the two groups with regard to preoperative data. Thymic hyperplasia was present in 45% of the young group and 16% of the elderly group. Remission and improvement rate were 40% and 57% in the young group and 8% and 75% in the elderly group, respectively. There were no serious complications, except one early death due to gastrointestinal bleeding in the elderly group. CONCLUSIONS We conclude that thymectomy is a safe and effective alternative for elderly patients with MG.

Predictive Risk Factors for Mediastinal Lymph Node Metastasis in Clinical Stage IA Non–Small-Cell Lung Cancer Patients

Introduction: Even for patients with clinical N0 non–small-cell lung cancer (NSCLC), several invasive tests are available to pathologically confirm the presumptive mediastinal stage by radiologic modalities. The aim of this study was to determine a high-risk population for mediastinal nodal metastasis in patients with clinical stage IA NSCLC, which would be suitable for mediastinal staging by invasive modalities, such as mediastinoscopy or endobronchial ultrasound-guided transbronchial needle aspiration. Methods: We retrospectively reviewed peripheral clinical stage IA NSCLC patients who had undergone surgical resection with systematic mediastinal lymphadenectomy from 1998 to 2011. To identify predictors for mediastinal nodal metastasis, univariate and multivariate logistic regression analyses were performed. For the significant factors, optimal cutoff points were determined with a receiver operating characteristic analysis. Results: Among the 894 patients eligible for this study, the overall prevalence of mediastinal nodal metastasis was 7.5%. The following four predictors for mediastinal nodal metastasis were identified: age, preoperative serum carcinoembryonic antigen level, tumor size on preoperative radiologic findings, and consolidation/tumor ratio on high-resolution computed tomography. Of the patients with all four predictors identified by the multivariate analyses and receiver operating characteristic analyses (age ⩽67 years, carcinoembryonic antigen ≥ 3.5 ng/ml, tumor size ≥ 2.0 cm, and consolidation/tumor ratio ≥ 89%), the prevalence of mediastinal nodal metastasis was 33.8%. Conclusions: Among the clinical stage IA NSCLC patients in whom all four predictors were identified, one third of the patients showed mediastinal nodal metastasis, and thus, those patients should be a target for mediastinal node assessment by invasive modalities, such as mediastinoscopy or endobronchial ultrasound-guided transbronchial needle aspiration.

Successful tracheal transplantation using cryopreserved allografts in a rat model

OBJECTIVES The purpose of this study was to determine the appropriate cryopreservation period of tracheal allografts based on morphological and immunological findings and to test the possibility of tracheal transplantation in rats using cryopreserved allografts without immunosuppression. METHODS Morphological and immunological studies were performed to compare the differences between non-cryopreserved grafts and cryopreserved grafts. Orthotopic tracheal transplantation using cryopreserved allografts, non-cryopreserved allografts, and non-cryopreserved autografts was performed and the rejection score of each group was evaluated. RESULTS Epithelial cells were lost when the grafts were cryopreserved for more than 20 days. Immunohistochemical staining of the trachea revealed that the MHC classII antigen was expressed on normal epithelium. These findings suggest that cryopreservation for more than 20 days decreased the antigeneicity of allografts because of epithelial desquamation. All rats that received allografts cryopreserved for more than 20 days survived until the scheduled sacrifice day. Microscopically, cryopreserved allografts that had been preserved for more than 20 days had a significantly lower rejection score than that of non-cryopreserved allografts (P < 0.05). CONCLUSIONS We conclude that the appropriate period for cryopreservation of allografts would be 20 days or more, because cryopreservation for more than 20 days depleted epithelium, which possessed the MHC classII antigen. Therefore, a longer period of cryopreservation decreases the antigeneicity of allografts. Rat tracheal transplantations using cryopreserved allografts is possible without immunosuppression when the grafts have been cryopreserved for more than 20 days.

Prognostic predictors in non-small cell lung cancer patients undergoing intentional segmentectomy.

BACKGROUND Despite recent studies reporting on the results of prospective intentional sublobar resection for patients with small non-small cell lung cancer (NSCLC), few studies have investigated predictors for prognosis or recurrence exclusively in patients undergoing intentional sublobar resection. METHODS We retrospectively reviewed 223 patients with small (2 cm or less) peripheral NSCLC who underwent intentional segmentectomy at the Niigata Cancer Center Hospital between 1992 and 2009. The significant demographic, clinical, and pathologic factors identified with the log rank test in univariate analyses were analyzed with the Cox proportional hazards regression model to examine independent predictors for prognosis and recurrence in multivariate analysis. RESULTS The 5-year and 10-year overall survival rates were 89.6% and 81.0%, respectively, and the 5-year and 10-year recurrence-free probabilities were 91.1% and 91.1%, respectively. Eight patients had locoregional recurrence, and 12 had distant recurrence. Multivariate analyses revealed that age more than 70 years (hazard ratio [HR] 2.389), male (HR 2.750), more than 75% consolidation/tumor ratio on high-resolution computed tomography (HR 2.750), and lymphatic permeation (HR 5.618) were independent poor prognostic factors, and lymphatic permeation (HR 16.257) was an independent predictor for recurrence. CONCLUSIONS The factors related to upstaging on pathologic diagnosis were not identified as independent predictors; therefore, the current patient selection criterion seems reasonable. If lymphatic permeation is present on pathologic findings, careful follow-up is recommended. The predictors identified in this study will support assessment and interpretation of the results of ongoing prospective randomized trials of lobar versus sublobar resection in patients with small peripheral NSCLC.

Results of surgical treatment for small (2 cm or Under) adenocarcinomas of the lung

PurposeThe objectives of this study were to identify the clinicopathologic characteristics and prognostic factors of small (2 cm or less in diameter) adenocarcinomas, and furthermore to assess the acceptability of performing a limited pulmonary resection in such patients.MethodsWe retrospectively reviewed 523 cases of cT1N0M0 peripheral adenocarcinoma measuring 2 cm or less on diagnostic images treated by a complete resection between 1991 and 2004.ResultsThe overall 5-year survival rate of the patients with small adenocarcinomas was 83.6%. Univariate and multivariate analyses identified an older age, male sex, wedge resection, advanced stage, and Noguchi classification of C, D, E, or F as independent prognostic factors that adversely affected overall survival. However, there were no significant differences in the survival according to surgical procedure in the patients whose tumors had a maximum diameter of 1.0 cm or less or in Noguchi type A and B cases.ConclusionsAge, sex, surgical procedure, p-stage, and Noguchi classification were independent prognostic factors for survival in patients with small adenocarcinomas. A segmentectomy is therefore considered to be an acceptable alternative to a lobectomy for adenocarcinomas of 2 cm or less in diameter. A wedge resection may be acceptable for tumors measuring 1 cm or less in diameter or Noguchi type A and B tumors.

Lobectomy Versus Segmentectomy in Radiologically Pure Solid Small-Sized Non-Small Cell Lung Cancer.

BACKGROUND The indication for limited resection of radiologically pure solid non-small cell lung cancer (NSCLC) is controversial owing to its invasive pathologic characteristics. This study was performed to compare the outcomes after lobectomy and segmentectomy in these NSCLC patients. METHODS We retrospectively reviewed 251 patients with radiologically pure solid cT1a N0 M0 NSCLC who underwent lobectomy or segmentectomy, and the preoperative characteristics of the patients treated with the two operative techniques were matched using propensity score methods. Overall survival (OS) and disease-free survival (DFS) curves were compared using the log rank test, and differences in survival were also evaluated by the McNemar test. The preoperative factors and surgical procedure were analyzed with the multivariate Cox proportional hazards regression model to identify independent predictors of poor OS and DFS. RESULTS In the propensity score matched lobectomy and segmentectomy groups (87 patients per group), the 5-year and 10-year OS rates were 85% versus 84% and 66% versus 63%, respectively; and the 5-year and 10-year DFS rates were 80% versus 77% and 64% versus 58%, respectively. There were no significant differences between the two groups in OS or DFS by the log rank test, and also no significant differences in 3-year, 5-year, or 7-year OS or DFS by the McNemar test. Although age, smoking status, pulmonary function, and carcinoembryonic antigen were identified as significant predictors of both OS and DFS, the surgical procedure was not identified. CONCLUSIONS Similar oncologic outcomes after lobectomy and segmentectomy were indicated among patients with radiologically pure solid small-sized NSCLC.

Successful surgical treatment of a ruptured abdominal aortic aneurysm without homologous blood transfusion in a Jehovah's Witness: report of a case.

Abstract We report herein the case of a 47-year-old woman of the Jehovahs Witness faith in whom Y-grafting for a ruptured abdominal aortic aneurysm was successfully performed without a homologous blood transfusion. We used a Cell Saver (Haemonetics, Braintree, MA, USA) red cell salvaging device and an aortic occlusion balloon catheter, and performed gentle and minimal dissection during the operation. Postoperatively, the patient was kept heavily sedated and required hypothermic therapy for only 14 h. We treated her severe anemia using conventional drugs, including iron and folic acid, and her hemoglobin increased smoothly. Although her hemoglobin level decreased to 2.8 g/dl during the operation, her postoperative course was uneventful.

Diagnostic yield of preoperative computed tomography imaging and the importance of a clinical decision for lung cancer surgery

PurposeThis study aimed to evaluate the diagnostic yield of preoperative computed tomography (CT) imaging and the validity of surgical intervention based on the clinical decision to perform surgery for lung cancer or suspected lung cancer.MethodsWe retrospectively evaluated 1755 patients who had undergone pulmonary resection for lung cancer or suspected lung cancer. CT scans were performed on all patients. Surgical intervention to diagnose and treat was based on a medical staff conference evaluation for the suspected lung cancer patients who were pathologically undiagnosed. We evaluated the relation between resected specimens and preoperative CT imaging in detail.ResultsA total of 1289 patients were diagnosed with lung cancer by preoperative pathology examination; another 466 were not pathologically diagnosed preoperatively. Among the 1289 patients preoperatively diagnosed with lung cancer, the diagnoses were confirmed postoperatively in 1282. Among the 466 patients preoperatively undiagnosed, 435 were definitively diagnosed with lung cancer, and there were 383 p-stage I disease patients. There were 38 noncancerous patients who underwent surgery with a diagnosis of confirmed or suspected lung cancer. Among the 1755 patients who underwent surgery, 1717 were pathologically confirmed with lung cancer, and the diagnostic yield of preoperative CT imaging was 97.8%. Among the 466 patients who were preoperatively undiagnosed, 435 were compatible with the predicted findings of lung cancer.ConclusionDiagnostic yields of preoperative CT imaging based on clinical evaluation are sufficiently reliable. Diagnostic surgical intervention was acceptable when the clinical probability of malignancy was high and the malignancy was pathologically undiagnosed.

Long-term survival after removal of a malignant peripheral nerve sheath tumor originating in the anterior mediastinum

Malignant peripheral nerve sheath tumors (MPNSTs; malignant schwannomas) rarely occur in the anterior mediastinum, and their prognosis is poor. A 75-year-old man was referred to our hospital for examination of an anterior mediastinal tumor. A computed tomography-guided percutaneous needle biopsy revealed only fibrosis. The tumor was completely excised via a median sternotomy with partial resection of the pericardium and right upper lobe of the lung. Thereafter, the tumor was diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma. At 1 year after the surgery, a distant metastasis was found in the interlobular space between the right middle and lower lobes. The tumor was completely excised via a right posterolateral thoracotomy. Reexamination of the primary and secondary tumors revealed an MPNST. No recurrence was found up to 5 years after the second surgery without adjuvant chemotherapy or radiation therapy. However, he died from multiple lung metastases after 6 years.