鈴木 秀海

PURPOSE: Recently, segmentectomy has been considered as an alternative to lobectomy in early peripheral non-small lung cancer (NSCLC); however, controversy has remained regarding the long-term functional advantage after segmentectomy. The aim of this study was to analyze the postoperative lung function after segmentectomy and lobectomy for non-small cell lung cancer. METHODS: Patients with p-T1aN0M0 NSCLC who had undergone segmentectomy (n = 37) or lobectomy (n = 33) were retrospectively analyzed. The ratios of postoperative to preoperative forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were defined as the recovery rates. The radiological lung volume and weight were evaluated before and more than 6 months after surgery, and the postoperative values were compared with the predicted values that were calculated from the preoperative values, subtracting the resected lobes or segments. RESULTS: The clinical characteristics, including the preoperative lung function showed no significant differences between the groups. No statistical differences were recognized in the trend lines for recovery ratios of FVC and FEV1.0 (P = 0.96 and P = 0.33). The recovery ratios for radiologic lung volume and weight showed no significant differences (P = 0.46 and P = 0.22). The postoperative lung volume and weight were almost the same as the predicted values after segmentectomy, whereas those after lobectomy were significantly higher than the predicted values. CONCLUSIONS: No functional advantage for segmentectomy was observed during long-term follow-up, possibly due to compensatory lung growth after lobectomy.

Objectives: Patients with thymoma are reported to have an increased risk for developing second malignancies. The aim of this study was to assess the incidence of second malignancies among patients with thymoma. We focused especially on the impact that lung cancer has on survival in these patients. Methods: Three hundred and thirty-five patients who underwent surgery for thymoma in Chiba University Hospital from January 1971 to November 2012 were included in this study. Patient records were reviewed retrospectively for data on background, treatment, second malignancies and clinical outcome. Results: Fourteen patients had a history of malignancy until the time of operation, with an additional 20 diagnosed simultaneously with the thymoma. Forty-three malignant lesions in 33 patients were found post-thymectomy. Lung cancer was diagnosed in 17 patients, far exceeding the expected number in the cohort, which was calculated according to Japanese national data. The median survival time of the thymoma patients who had lung cancer at the time of surgery was 5.8 years. The survival of patients with thymoma and lung cancer was poor in comparison with that of others. Conclusions: Secondary lung cancer is frequently found in thymoma patients and could be one of the factors limiting survival. We recommend an annual computed tomographic scan of the thorax to detect not only recurrent thymoma but also lung cancer at an early stage in order to improve the survival of these patients.

BACKGROUND: Lung carcinoma is often associated with interstitial lung disease (ILD), and the prognosis of lung cancer accompanied by ILD is unfavorable. In this study, cases of patients with primary lung cancer with or without ILD were reviewed to analyze surgical outcome, with special interest in the conformity of clinical and pathologic stages, pathologic findings of pleural invasion, malignant pleurisy first detected at the time of thoracotomy, and survival. METHODS: Retrospective chart review was performed for 1,264 primary lung cancer patients who underwent surgery from 2004 to 2015. Concomitant ILD was diagnosed by pathological examination or preoperative chest computed tomography findings. RESULTS: ILD was found in 104 patients (8.2%) with primary lung cancer. Conformity of clinical and pathological stages in the ILD-positive patients was poor, with a lower kappa value than that for the 1,160 ILD-negative patients (0.34 versus 0.51). The ILD group had significantly higher incidences of pleural invasion and unexpected malignant pleurisy than did the non-ILD group (for pleural invasion, 49.0% versus 24.5%, p < 0.0001; for malignant pleurisy, 7.69% versus 1.47%, p < 0.0001). The 5-year overall survival rates of the ILD group showed significantly lower than those of the non-ILD group (45.2% versus 70.1%; p = 0.0014) after propensity score matching. CONCLUSIONS: In lung cancer, the concomitant existence of ILD is a risk factor for pleural invasion. Concomitant ILD might cause underestimation of clinical staging, increase the chance of unexpected malignant pleurisy during surgery, and shorten survival time.

Training for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has focused on the procedure itself; however, the techniques for obtaining adequate sample are also important for achieving a pathological diagnosis as well as for molecular testing. The aim of this study was to evaluate the feasibility and efficacy of a biosimulator for training subjects in adequate sample acquisition during EBUS-TBNA.A total of 19 bronchoscopists voluntarily participated in this study. A biosimulator (ArtiCHEST, HARADA Corporation, Tokyo, Japan) was used for the training. After a 10-minute briefing, the first pass was performed by pairs of trainees. The trainees then received a 30-minute lecture that focused on the acquisition of samples using EBUS-TBNA. The trainees next performed their second pass under the supervision of the trainers. Each participant obtained a cytological smear that was coded and evaluated for quantity as well as quality by an independent cytotechnologist.The trainees had an average of 5.9 years of bronchoscopy experience. With regard to the quantity evaluation, 9 (47.4%) subjects sampled a greater number of lymphocytes on the second pass than on the first, whereas 2 were better on the first pass, and the others sampled roughly the same amount both times. With regard to the quality assessment, 9 (47.4%) subjects obtained better quality samples on the second pass, whereas the quality of the first and second pass was deemed to be roughly the same for the remaining subjects.A biosimulator can be used to train doctors in specimen acquisition and evaluate their skills with sampling using EBUS-TBNA.

背景. EBUS-TBNA施行後の脳梗塞に対し、遺伝子組み換え組織型プラスミノゲン活性化因子(rt-PA)による血栓溶解療法を施行した症例を経験した。症例. 77歳男性。左肺癌に対し左肺上葉切除後1年で、呼吸困難を主訴に入院となった。胸部CT上心嚢水の貯留、#7リンパ節の腫大を認めた。悪性心嚢水は認めなかった。#7リンパ節に対しEBUS-TBNAを施行し、炎症による反応性リンパ節腫大と診断した。EBUS施行後、病棟での経過観察中(EBUS施行後8時間)に左片麻痺が出現し、脳梗塞が疑われた。脳MRIを施行し、急性期脳梗塞に矛盾しない所見を認め、ICU管理のもとで経静脈的にrt-PA投与を行った。rt-PA療法に伴う気道出血などの合併症は認めなかった。左片麻痺は徐々に改善し、EBUS施行後第21病日にリハビリ目的に転院となった。考察. 生検後脳梗塞発症症例に対してのrt-PA療法は慎重投与の適応とされる。EBUS-TBNA施行後にrt-PA療法を行った報告はこれまでなく、文献的考察も含めて報告する。(著者抄録)

Primary chest wall tumors (PCWTs) are relatively rare entities, and their clinical characteristics as well as appropriate treatments are not fully known. Previously reported studies, including ours, are reviewed here, taking into account the clinical approach and findings in Japan for the diagnosis, distribution of histological types, surgical procedures, and prognosis of these entities. Surgery for PCWTs comprised that approximately 0.7 % of surgeries in 2012 in Japan and 28.3 % of PCWTs were malignant with an extremely low rate of mortality within 30 days from surgery. Surgical biopsy is recommended for the differential diagnosis of chest wall tumors to determine if they are primary, metastatic, benign, or malignant lesions. Of the 297 PCWT cases reported in nine published studies, neurogenic tumors were the most common benign PCWT, and chondrosarcoma was the most common malignant PCWT. Reconstruction of the resected chest wall was performed for 41.3 % of cases, and the materials used were e-PTFE or polypropylene. The prognosis of patients with benign tumors is usually good if complete resection is achieved; however, the 5-year recurrence rate and disease-related mortality were approximately 22.5 and 18.1 %, respectively, for patients with malignant tumors. Surgery for PCWTs is safe; however, surgical treatment for patients with malignant PCWTs remains challenging, and multimodal treatments for each histological tumor type should be considered.

BACKGROUND: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is a life-threatening complication of lung cancer operation for patients with IPF, and no effective prophylaxis has ever been reported. In this study, we investigate the effect of perioperative treatment with an anti-IPF agent on reduction of the risk of developing AE-IPF. METHODS: A consecutive series of 50 lung cancer patients with IPF who underwent operations at our institution from October 2006 to October 2014 was retrospectively investigated. Since September 2009, pirfenidone was orally administered to patients from 4 weeks before operation to 4 weeks after operation. Thirty-one patients received the perioperative pirfenidone treatment (PPT), and their clinical outcome was retrospectively compared with that of 19 patients who did not receive PPT. RESULTS: No differences were found in age, smoking history, sex, vital capacity, KL-6, procedure, or risk score (10.5 ± 2.2 versus 11.2 ± 1.5) between the PPT and non-PPT groups. The incidence of AE-IPF for the PPT/non-PPT groups was 0.0%/10.5% within 30 postoperative days (p = 0.07) and 3.2%/21.1% within 90 postoperative days (p = 0.04), respectively. Logistic regression analysis showed a significant association between PPT and the incidence of AE-IPF within 30 (p = 0.045) and 90 (p = 0.04) postoperative days. CONCLUSIONS: A prophylactic effect of PPT for postoperative AE-IPF in patients with lung cancer was suggested. Further confirmatory prospective studies should be considered for PPT.

Postoperative atrial fibrillation (POAF), the most frequent arrhythmia after pulmonary resection, is a cause of both morbidity and mortality. Being able to predict the risk of POAF before surgery would help us evaluate the surgical risk and plan prophylaxis. We investigated the reported preoperative risk factors associated with the incidence of POAF and found that the recommended predictive factors were quite variable. Therefore, we evaluated the previously reported preoperative risk factors for POAF using our institutional data. We discuss our findings in this short review. Male gender, resected lung volume, brain natriuretic peptide (BNP), and left ventricular early transmitral velocity/mitral annular early diastolic velocity (E/e′) calculated by echocardiography were suggested as independent predictors for POAF, but the predictive values of each individual parameter were not high. The lack of definitive predictors for POAF warrants further investigations by gathering the reported knowledge, to establish an effective preoperative examination strategy.

PURPOSE: Cerebral infarction is a rare complication of lung resection that can result in severe sequelae. Our aim was to investigate the characteristics of patients who suffer from cerebral infarction after surgery for lung cancer. METHODS: We retrospectively reviewed all patients who underwent resection of at least a single lobe for lung cancer at our institution between January 2008 and October 2013. We compared the patients who presented with cerebral infarction with those patients who did not within 30 days of surgery. RESULTS: A total of 562 patients underwent surgery, with five males and one female subsequently experiencing cerebral infarction. Five patients underwent left upper lobectomy and one underwent left lower lobectomy. Patient age, sex, body mass index, smoking index, and operative time were not significantly different between the six patients with postoperative cerebral infarction and the other 556 patients; only the type of operative procedure was significantly different (p < 0.001). Contrast-enhanced computed tomography revealed thrombosis in the stump of the left superior pulmonary vein in patients with postoperative cerebral infarction. CONCLUSIONS: Cerebral infarction occurs at a high frequency in patients who undergo left upper lobectomy for lung cancer. Thrombosis in the left superior pulmonary-vein stump might cause cerebral infarction.

OBJECTIVE: Pulmonary adenocarcinoma with a micropapillary component (MPC) has aggressive malignant behavior even if resectable. The aim of this study was to determine clinicopathologic features of patients who underwent surgery for pulmonary adenocarcinoma harboring MPCs, with particular focus on coexistent free tumor clusters (FTCs). METHODS: We retrospectively reviewed 444 patients with pulmonary adenocarcinoma who underwent surgery from March 2007 to July 2013. An MPC was defined as a >5% micropapillary pattern. We also defined FTCs to be a group of more than 3 small clusters containing <20 nonintegrated micropapillary tumor cells that were spreading within air spaces, >3 mm apart from the main tumor. The clinicopathologic characteristics of patients with and without FTCs were retrospectively investigated in MPC-positive patients. RESULTS: MPCs were identified in 67 patients (15.1%), 31 of whom (46.3%) were positive for FTCs. The distance between the furthest edge of FTCs and main tumors did not exceed the diameter of the main tumor in each case (average, 7.3 mm). Locoregional recurrences were frequently observed in FTC-positive patients. FTC-positive patients experienced a significantly lower 5-year recurrence-free survival rate compared with FTC-negative/MPC-positive patients (20.4% vs 52.2%, P < .001). Recurrence-free survival of FTC-negative and -positive patients was equivalent to that of patients with p-T2 and p-T3 MPC-negative adenocarcinoma, respectively. CONCLUSIONS: Coexistence of FTCs resulted in a further negative impact on postoperative prognosis among MPC-positive adenocarcinomas and should be considered for upstaging the p-T factor and during evaluation of surgical margins.