鈴木 秀海

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.