Hee Chul Yang

Predictive factors for node metastasis in patients with clinical stage I non-small cell lung cancer.

BACKGROUND Accurate clinical staging of non-small cell lung cancer (NSCLC) is essential for developing a treatment plan and evaluating suitability for minimally invasive surgery. The aim of this study was to evaluate predictive factors for metastasis of N1 and N2 nodes in clinical stage I NSCLC. METHODS Records of patients with clinical stage I NSCLC who had undergone pulmonary resection with systematic node dissection or node sampling between 2003 and 2011 were retrospectively reviewed. To identify predictive factors for node metastasis, univariate and multivariate logistic regression analyses were performed. RESULTS Among the 770 patients in this study, the overall prevalence of node metastasis was 19.4%, which included 11.3% of N1 nodes and 8.1% of N2 nodes. Predictive factors for N1 node metastasis included male sex, current smoker, non-adenocarcinoma, solid consistency, centrally located tumor, clinical T stage, cytokeratin fragment 21-1 level, tumor size, maximum standardized uptake value of the mass, and ground-glass opacity proportion. Adenocarcinoma, solid consistency, clinical T stage, carcinoembryonic antigen level, tumor size, and ground-glass opacity proportion were identified as predictors for N2 node metastasis. Both tumor size and solid consistency were independent predictive values of N1 node and N2 node metastasis by multivariate analysis. CONCLUSIONS Among the patients with clinical stage I NSCLC, 19.4% of the patients showed unexpected node metastasis, and large size and solid consistency of the tumor were predictive factors of node metastasis in clinical stage I NSCLC. Preoperative staging should be performed more thoroughly to increase the accuracy of preoperative staging, especially in those who have the larger size and solid consistency of the tumor.

Prognostic factors of pulmonary metastasis from colorectal carcinoma

OBJECTIVES This study was conducted to investigate the prognostic factors of pulmonary metastases, focusing on the time of detection of pulmonary metastases related to adjuvant chemotherapy in patients with colorectal cancer (CRC). METHODS Between June 2003 and December 2010, 84 patients underwent pulmonary metastasectomy for pulmonary metastasis (PM) from CRC. The clinicopathological data of colorectal surgery and pulmonary metastasectomy were analysed retrospectively. Disease-free intervals (DFIs) were specifically classified into the following three groups related to adjuvant chemotherapy after colorectal operation: Group 1, metastasis detected at initial presentation; Group 2, metastasis detected during adjuvant chemotherapy; Group 3, metastasis detected after completion of chemotherapy. The prognostic influence of these variables on disease-free survival was analysed using the log-rank test for univariate analysis and the Cox proportional hazards model for multivariate analysis. RESULTS The median follow-up durations for patients after curative resection of CRC and pulmonary metastasectomy were 48.6 and 28.8 months, respectively. After pulmonary metastasectomy, recurrence was seen in 49 (58.3%) patients-pulmonary recurrence in 37 and extrathoracic recurrence in 12. Young age (<54 years old) at CRC operation, more than one PM, a DFIs of <12 months, detection synchronously or under adjuvant chemotherapy, and high CEA level before metastasectomy were worse prognostic factors by univariate analysis. From multivariate analysis, the number of pulmonary metastases (multiple metastases, HR=2.121, 95% confidence interval 1.081-4.159, P=0.029) and DFIs related with adjuvant chemotherapy (Group 1+2, HR=1.982, 95% confidence interval 1.083-3.631, P=0.027) were found to be independent predictors of disease-free survival. CONCLUSIONS Disease-free intervals in association with the time of adjuvant chemotherapy and number of metastases were independent poor prognostic factors for pulmonary metastases from colorectal cancer.

The effect of postoperative change in bronchial angle on postoperative pulmonary function after upper lobectomy in lung cancer patients

OBJECTIVES Upper lobectomy inevitably leads to an upward displacement of the remaining lower lobe. Such displacement may result in bronchial angulation, thereby narrowing the airway. We hypothesized that the degree of displacement of the bronchus is associated with the degree of exacerbation of postoperative pulmonary dysfunction. This study investigated whether bronchial angulation affects postoperative pulmonary function. METHODS Patients undergoing upper lobectomy for lung cancer were retrospectively evaluated. A check for the presence of dyspnoea, pulmonary function test, chest X-ray and chest computed tomography (CT) were performed at 3 and 12 months postoperatively in these patients. The angle formed by the main bronchus and the bronchus intermedius on the right side and that by the main bronchus and the lower lobar bronchus were measured using the coronal view of the chest CT. We analysed the relationship between the change in bronchial angle and pulmonary function. RESULTS Ninety-nine patients were enrolled in this study. Among these patients, 50 underwent left upper lobectomy (LUL) and 49 underwent right upper lobectomy (RUL). Nine patients who underwent LUL showed worsening symptoms, and among them, 8 presented an increase in the angle. However, among the 9 patients with worsening symptoms after RUL, only 4 presented an increase in the angle. Decreased forced expiratory volume in 1 s (FEV1) from 3 to 12 months after surgery was observed in 16 patients in the LUL group and 14 in the RUL group. Exacerbation of pulmonary dysfunction was associated with an increase in the bronchial angle (P = 0.04 for LUL and P = 0.02 for RUL). The degree of angle change was also associated with the extent of FEV1 reduction (P = 0.02 for LUL and P = 0.02 for RUL). CONCLUSIONS Although the change in the bronchial angle is a physiological condition, it can reduce postoperative pulmonary function. The measurement of the change in the angle using the coronal view of a chest CT is a useful screening tool for predicting the postoperative reduction in FEV1.

Preoperative thrombocytosis is a significant unfavorable prognostic factor for patients with resectable non-small cell lung cancer

BackgroundPrevious studies have reported that pretreatment thrombocytosis is associated with poor outcomes in several cancer types. This study was designed to evaluate the prognostic significance of preoperative thrombocytosis in patients with non-small cell lung cancer (NSCLC) who undergo surgery.MethodsWe retrospectively reviewed the records of 199 patients who underwent R0 resection for NSCLC between May 2003 and July 2006 at Seoul National University Bundang Hospital, Seongnam, Korea.ResultsThe frequency of preoperative thrombocytosis was 7.5% (15/199). Patients with preoperative thrombocytosis had shorter overall survival (OS, P = 0.003) and disease-free survival (DFS, P = 0.005) than those without thrombocytosis. In multivariable analysis, patients with preoperative thrombocytosis had a significantly greater risk of death and recurrence than those without preoperative thrombocytosis (risk of death: hazard ratio (HR) 2.98, 95% confidence interval (CI) 1.39 to 6.37, P = 0.005; risk of recurrence: HR 2.47, 95% CI 1.22 to 5.01, P = 0.012). A tendency towards a shorter OS and DFS was observed in three patients with persistent thrombocytosis during the follow-up period when compared with those of patients who recovered from thrombocytosis after surgery.ConclusionsPreoperative thrombocytosis was valuable for predicting the prognosis of patients with NSCLC. Special attention should be paid to patients with preoperative and postoperative thrombocytosis.

Inactivation of multidrug resistant (MDR)- and extensively drug resistant (XDR)-Mycobacterium tuberculosis by photodynamic therapy

We investigated the effects of photodynamic therapy (PDT) on anti-tuberculosis (TB) activity by measuring inactivation rates, expressed as D-value, of MDR- and XDR-Mycobacterium tuberculosis (M. tb) clinical strains in vitro. Approximately 10(6) colony forming unit per milliliter (CFU/ml) of the bacilli were irradiated with various doses of laser light after exposure to photosensitizers. Survival of M. tb was measured by enumerating CFU in 7H10 medium to measure D-values. No inactivation of M. tb was observed when exposed to photosensitizers (radachlorin or DH-I-180-3) only or laser light only (P>0.1). Treatment with a combination of photosentizer and laser inactivated M. tb although there was a significant difference between the types of photosensitizers applied (P<0.05). Linear inactivation curves for the clinical M. tb strains were obtained up to laser doses of 30 J/cm(2) but prolonged irradiation did not linearly inactivate M. tb, yielding sigmoid PDT inactivation curves. D-values of M. tb determined from the slope of linear regression lines in PDT were not significantly different and ranged from 10.50 to 12.13 J/cm(2) with 670 nm laser irradiation at 100 mW/cm(2) of the fluency rate, except for a drug-susceptible strain among the clinical strains tested. This suggests that PDT inactivated M. tb clinical strains regardless of drug resistance levels of the bacilli. Intermittent and repeated PDT allowed acceleration of the inactivation of the bacilli as a way to avoid the sigmoid inactivation curves. In conclusion, PDT could be alternative as a new option for treatment for MDR- and XDR-tuberculosis.

Frequency of Lymph Node Metastasis According to the Size of Tumors in Resected Pulmonary Adenocarcinoma with a Size of 30 mm or Smaller

Background: This study analyzed the relation between the tumor size and the lymph node metastasis in adenocarcinoma of the lung with a size of 30 mm or smaller. Methods: Four hundred thirteen patients who had undergone curative resection for lung adenocarcinoma were enrolled. If the tumor presented ground-glass opacities on the preoperative high-resolution computed tomography, both the total size including ground-glass opacities and the solid size alone were measured. To calculate the rates of lymph node metastasis by the tumor size, the tumors were divided into six groups by their sizes: 5 mm or less, 6 to 10 mm, 11 to 15 mm, 16 to 20 mm, 21 to 25 mm, and 26 to 30 mm. Results: The average numbers of dissected lymph nodes and dissected lymph node stations were 17 and 5, respectively. Seventy-five patients (18%) were postoperatively discovered to have positive nodes. The rates of node metastasis in each total size group were 0/1 (0%), 0/29 (0%), 5/77 (7%), 17/121 (14%), 27/101 (27%), and 26/84 (31%), respectively. The rates of node metastasis in each solid size group were 0/37 (0%), 1/53 (2%), 9/88 (10%), 17/104 (16%), 23/78 (30%), and 25/53 (47%), respectively. The area under the curve of receiver operating characteristic curves for the total size was measured as 0.701, and that for the solid size was measured as 0.777. By multivariate analysis, solid size, maximum standardized uptake value, and lymphovascular invasion were independent significant predictive factors. Conclusions: Solid size, maximum standardized uptake value, and lymphovascular invasion were independent predictors for lymph node metastasis of lung adenocarcinoma. The size of the solid component explained the relation between the tumor size and the lymph node metastasis more accurately than that explained by the total tumor size on high-resolution computed tomography.

Prognostic factors for post-recurrence survival in patients with completely resected Stage I non-small-cell lung cancer

OBJECTIVES The clinical course from recurrence to cancer-related death after curative resection has not been clearly elucidated in non-small-cell lung cancer (NSCLC). This study examined the clinical outcomes after postoperative recurrence in patients with completely resected Stage I NSCLC. METHODS This study included patients who had recurrence after complete resection for pathological Stage I NSCLC between 2003 and 2009. Clinical data evaluated in this study included the diagnostic process of recurrence, recurrence pattern, treatment process and prognosis. A number of clinicopathological factors were analysed for post-recurrence survival by univariate and multivariate analyses. RESULTS Seventy-two patients experienced recurrence during a median follow-up period of 37.5 months. Thirteen patients (18%) presented symptoms at the initial recurrence. Tumour markers, computed tomography (CT) and positron emission tomography/CT were chosen as the initial diagnostic tools and detected recurrences in 1 (1%), 51 (71%) and 7 (10%) patients, respectively. The mean recurrence-free interval (RFI) was 15.4 months (≤12 months in 34, >12 months in 38 patients). The patterns of recurrence were presented as loco-regional recurrence in 36 (50%) and distant metastasis in 36 patients (50%). Types of the initial treatment included operations in 28 (39%), chemotherapy and/or radiotherapy in 38 (53%) and radiofrequency ablation in 2 patients (3%). Four patients (6%) rejected treatment. Forty-three patients (62%) presented a good response to the initial treatment. Thirty-seven patients (51%) died, and the cause of death in all of these patients was cancer-related. The median survival duration after recurrence was 43.6 (1-136) months. Univariate analysis identified no recurrence of symptoms, a good response to treatment and a longer RFI as good prognostic factors, while a good response to treatment and a longer RFI were independent prognostic factors in multivariate analysis. CONCLUSIONS Most postoperative recurrences were detected in an asymptomatic condition during the routine follow-up period, and a good response to initial treatment and a longer RFI were significant predictors of better post-recurrence survival in patients with completely resected Stage I NSCLC.

Video-assisted thoracic surgery for lung cancer

Video-assisted thoracic surgery (VATS) lobectomy is currently accepted as an appropriate procedure for selected patients with early-stage non-small-cell lung cancer (NSCLC). Evidence has demonstrated that VATS lobectomy is not only a safe and feasible technique, it provides better functional recovery and oncological efficacy similar to that achieved with conventional thoracotomy. However, there are still ongoing issues concerning VATS in terms of terminology, oncological efficacy, functional recovery, benefit of screening detected lung cancer, and its role in limited resection. As the number of VATS procedures are increasing and VATS is becoming a dominant procedural choice, it would be wise to collect evidence and come to a consensus to justify the expansion of surgical indications for VATS.

Pain control of thoracoscopic major pulmonary resection: is pre-emptive local bupivacaine injection able to replace the intravenous patient controlled analgesia?

BACKGROUND The aim of this open-label, non-inferiority trial was to evaluate whether pre-emptive local bupivacaine injection (PLBI) can replace intravenous patient controlled analgesia (IV PCA) in video-assisted thoracic surgery (VATS) major pulmonary resection. METHODS A total of 86 patients scheduled for VATS segmentectomy/lobectomy were randomly assigned into two groups. The PLBI group (n=42) received 0.5% bupivacaine wound infiltration before skin incision, and the IV PCA group (n=44) received a continuous infusion of fentanyl with a basal rate of 10 µg/mL/h. Visual analogue scale (VAS; range, 0-10) was measured as the primary endpoint. The secondary endpoint was an additional use of analgesics and drug induced side effects. RESULTS Both groups showed no difference in terms of age, sex, disease entity, operation time, chest tube indwelling time, and hospital stay. Serial pain scores between the PLBI and IV PCA groups demonstrated no statistical differences (non-inferiority margin; ΔVAS =1.0) (Recovery room: 8.3±2.1 vs. 8.5±1.7; Day 0: 5.1±1.6 vs. 5.2±1.4; Day 1: 3.5±1.6 vs. 3.3±1.2; Day 2: 2.7±1.3 vs. 2.5±1.2; Day 3: 2.3±1.3 vs. 2.1±1.5; 1 week after discharge: 3.0±1.7 vs. 2.8±1.5; 1 month: 1.9±1.2 vs. 2.3±1.4 and 2 months: 1.5±1.2 vs. 1.3±1.2; 95% confidential interval (CI) of ΔVAS <1.0; P>0.05). The mean one-additional usage of IV analgesics was needed in the PLBI group (3.3±2.1 vs. 2.3±1.3; P=0.03). The occurrence of nausea/vomiting was higher in the IV PCA group (12.5% vs. 38.9%; P=0.026) and 41.7% of IV PCA patients experienced drug side effects that required IV PCA removal within postoperative day (POD) 1. CONCLUSIONS PLBI is a simple, safe, effective, and economical method, which is not inferior to IV PCA in VATS major pulmonary resection.

Evaluation of decortication in patients with chronic tuberculous empyema by three-dimensional computed tomography densitometry.

BACKGROUND Decortication for chronic pleural empyema (CPE) is to restore lung volume by removing empyema sac and thickened pleura. Extent of lung volume restoration after decortication has been undefined. This study aims to evaluate lung volume restoration using densitometry with three-dimensional reconstruction computed tomography (CT). METHODS We studied 23 patients with CPE who underwent decortication and follow-up CT. CT and pulmonary function test (PFT) were evaluated at a median of 19.1 months postoperatively. The volumes of operated and nonoperated lung were measured by pre- and postoperative CT-densitometry. Preoperative and postoperative values of lung volumes, PFTs, and thoracic asymmetry rates were compared statistically. RESULTS The mean preoperative volumes of operated and nonoperated lung were 1,239 and 2,094 mL, respectively and 1,848 and 2,311 mL postoperatively. The postoperative lung expansion rate was 71% on the operated side (p < 0.001) and 15% on the nonoperated side (p = 0.026). The mean improvement rate of total lung volume was 31%. The postoperative value of forced vital capacity, forced expiratory volume during 1 second and lung diffusion capacity of carbon monoxide improved 28.0%, 27.4% (p < 0.001), and 17.9% (p < 0.012), respectively. The thoracic asymmetry decreased from 4.3% before surgery to 2.8% after surgery (p = 0.026). CONCLUSIONS With the use of CT-densitometry, we quantified the changes of each lung volume. Decortication for CPE can improve re-expansion of diseased and healthy lung. Improvement of nonoperated lung may be due to the overall improvement of chest wall elasticity. Coincidentally, we discovered that the improvement of total lung volume was positively associated with the improvement of PFT after decortication.