Yukio Saitoh

High magnification bronchovideoscopy combined with narrow band imaging could detect capillary loops of angiogenic squamous dysplasia in heavy smokers at high risk for lung cancer

Background: We investigated the use of high magnification bronchovideoscopy combined with narrow band imaging (NBI) for the detailed examination of angiogenic squamous dysplasia (ASD). This was carried out in relation to bronchial vascular patterns with abnormal mucosal fluorescence in heavy smokers at high risk for lung cancer. Methods: Forty eight patients with sputum cytology specimens suspicious or positive for malignancy were entered into the study. Conventional white light and fluorescence bronchoscopic examination was first performed. Observations by high magnification bronchovideoscopy with conventional white light were made primarily at sites of abnormal fluorescence, and then repeated with NBI light to examine microvascular networks in the bronchial mucosa. Spectral features on the RGB (Red/Green/Blue) sequential videoscope system were changed from the conventional RGB broadband filter to the new NBI filter. The wavelength ranges of the new NBI filter were B1: 400–430 nm, B2: 420–470 nm, and G: 560–590 nm. ASD tissues were also examined using a confocal laser scanning microscope equipped with argon-krypton (488 nm) and argon (514 nm) laser sources. Results: The microvessels, vascular networks of various grades, and dotted vessels in ASD tissues were clearly observed in NBI-B1 images. Diameters of the dotted vessels visible on NBI-B1 images agreed with the diameters of ASD capillary blood vessels diagnosed by pathological examination. Capillary blood vessels were also clearly visualised by green fluorescence by confocal laser scanning microscopy. There was a significant association between the frequency of dotted vessels by NBI-B1 imaging and tissues confirmed as ASD pathologically (p=0.002). Conclusions: High magnification bronchovideoscopy combined with NBI was useful in the detection of capillary blood vessels in ASD lesions at sites of abnormal fluorescence. This may enable the discrimination between ASD and another pre-invasive bronchial lesion.

Smoking before surgery predicts poor long-term survival in patients with stage I non-small-cell lung carcinomas.

PURPOSE The majority of lung carcinoma patients requiring resection have smoking habits prior to surgical treatment, and the correlation of smoking with postoperative complications is well known. However, few studies have investigated the correlation between long-term survival and cigarette smoking in patients with primary, resected lung carcinoma. We analyzed the relationship between clinical factors, including cigarette smoking before surgery, and 10-year survival in stage I non-small-cell lung carcinoma (NSCLC). PATIENTS AND METHODS Cigarette smoking habit and other factors influencing either the overall survival or the disease-specific survival rates of patients with stage I primary, resected NSCLC were evaluated according to the Cox proportional hazards model using a total of 369 patients with stage I-NSCLC. RESULTS Comparison of the cause of death in patients with 30 or more pack-years and patients with less than 30 pack-years showed significant differences in the prevalence of recurrent disease and onset of nonmalignant disease. Multivariate analysis demonstrated significant correlations between overall survival and age and pack-years. Disease-specific survival showed significant correlations with age, tumor classification, and visceral pleural invasion. CONCLUSION Smoking pack-years is an important clinical prognostic factor in evaluating overall long-term survival in patients with stage I primary, resected NSCLC.

Fluorescence bronchoscopy in the detection of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy

BACKGROUND A new strategy in the treatment of squamous cell carcinoma of the tracheobronchial tree is the detection and eradication of preinvasive bronchial lesions before they become invasive cancers. It is, however, difficult to detect preinvasive lesions by conventional white-light bronchoscopy alone. PURPOSE we conducted a detailed investigation on the use of fluorescence bronchoscopy in the detection of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy. METHODS 64 participants with sputum cytology suspicious or positive for malignancy were examined with both white light and fluorescence bronchoscopy (LIFE group). Earlier to this study, before fluorescence bronchoscopy became available in our institute, 48 participants having sputum cytology suspicious or positive for malignancy were examined with white light bronchoscopy alone (control group). Biopsy specimens for pathological examinations were taken of all abnormal areas discovered by white light or fluorescence bronchoscopy examination. RESULTS In sputum cytology suspicious or positive for malignancy, the diagnosis of preinvasive bronchial lesions was greatly enhanced in the LIFE group as compared with the control group (45 vs. 7 lesions). The percentage of participants with preinvasive bronchial lesions was also significantly higher in the LIFE group than in the control group (40.6 vs. 12.5%, P = 0.00087, respectively). CONCLUSIONS Our study suggests that the use of fluorescence bronchoscopy in addition to conventional white-light examination could greatly enhance the detection and localization of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy.

Subepithelial vascular patterns in bronchial dysplasias using a high magnification bronchovideoscope

Background: We have developed a method of high magnification bronchovideoscopy that enables improved observation of subepithelial vascular patterns of the bronchial mucosa. A study was undertaken to investigate the value of high magnification bronchovideoscopy in the detailed examination of dysplasia in the bronchial mucosa of patients with abnormal mucosal fluorescence. Methods: Thirty one patients with sputum cytology specimens suspicious or positive for malignancy were entered into the study. Conventional white light examination was first performed under local anaesthesia and fluorescence bronchoscopy was also carried out using a light induced fluorescence endoscopy (LIFE) lung system. A high magnification bronchovideoscope (XBF 200HM2) was then used to examine the microvascular network in the bronchial mucosa at sites of normal and abnormal fluorescence and the images obtained were compared with pathological diagnoses from bronchial biopsy specimens. Vascular area ratios were calculated using image analysing apparatus. Results: Vascular networks with regular patterns were observed at 20 of 22 abnormal fluorescence sites in biopsy specimens from patients with bronchitis. However, vascular networks with increased vessel growth and complex networks of tortuous vessels of various sizes were observed in 15 of 21 abnormal fluorescence sites in dysplasia specimens. There was a significant difference between bronchitis and dysplasia specimens (OR=25, 95% CI 5.5 to 113, p<0.0001). Mean vascular area ratios from 16 normal bronchial epithelium specimens with normal fluorescence, and 22 bronchitis and 21 dysplasia specimens with abnormal fluorescence were 0.054 (95% CI 0.039 to 0.07), 0.095 (95% CI 0.072 to 0.118), and 0.173 (95% CI 0.143 to 0.203), respectively. The results indicate a statistically significant increase in vascular area in the three groups (p<0.0001). Conclusion: Areas of increased vessel growth and complex networks of tortuous vessels in the bronchial mucosa detected using a high magnification bronchovideoscope at sites of abnormal fluorescence may enable discrimination between bronchitis and dysplasia.

Impact of interstitial lung disease on surgical morbidity and mortality for lung cancer: analyses of short-term and long-term outcomes

BACKGROUND This study investigated postoperative morbidity, mortality, and the long-term survival for patients with lung cancer who have interstitial lung diseases. METHODS A retrospective chart review of 931 patients with lung cancer who underwent pulmonary resection at Chiba University Hospital between 1990 and 2000 was undertaken. Interstitial lung disease was defined by medical history, physical examination, and abnormalities compatible with bilateral lung fibrosis on chest computed tomography or high-resolution computed tomography (36 patients: 3.9%, interstitial lung diseases group). The remaining 895 patients (96.1%) were categorized as non-interstitial lung disease group. RESULTS The incidence of postoperative pneumonia and acute or exacerbation of interstitial pneumonia was higher in the interstitial lung disease group (all P <.05). Thirty-day mortality was statistically equivalent between the interstitial lung disease and the non-interstitial lung disease groups (P =.30). The 5-year overall survivals were 62.5% (non-interstitial lung disease) and 35.6% (interstitial lung disease). Respiratory failure was the second main cause of death after the recurrence of primary cancer in the interstitial lung disease group. The risk factors for long-term mortality were interstitial lung diseases, advanced pathologic stage, male sex, high age, and positive smoking history (all P <.05). CONCLUSIONS Interstitial lung disease was a risk factor for developing postoperative morbidity and mortality and poor long-term survival due to the occurrence of respiratory failure.

Minimal alteration of pulmonary function after lobectomy in lung cancer patients with chronic obstructive pulmonary disease.

BACKGROUND The aim of this study was to evaluate the influence of chronic obstructive pulmonary diseases (COPD) on postoperative pulmonary function and to elucidate the factors for decreasing the reduction of pulmonary function after lobectomy. METHODS We conducted a retrospective chart review of 521 patients who had undergone lobectomy for lung cancer at Chiba University Hospital between 1990 and 2000. Forty-eight patients were categorized as COPD, defined as percentage of predicted forced expiratory volume at 1 second (FEV1) less than or equal to 70% and percentage of FEV1 to forced vital capacity less than or equal to 70%. The remaining 473 patients were categorized as non-COPD. RESULTS Although all preoperative pulmonary function test data and arterial oxygen tension were significantly lower in the COPD group, postoperative arterial oxygen tension and FEV1 were equivalent between the two groups, and the ratio of actual postoperative to predicted postoperative FEV1 was significantly better in the COPD group (p < 0.001). With multivariable analysis, COPD and pulmonary resection of the lower portion of the lung (lower or middle-lower lobectomies) were identified as independent factors for the minimal deterioration of FEV1. Actual postoperative FEV1 was 15% lower and higher than predicted, respectively, in the non-COPD patients with upper portion lobectomy and the COPD patients with lower portion lobectomy. Finally, we created a new equation for predicting postoperative FEV1, and it produced a higher coefficient of determination (R(2)) than the conventional one. CONCLUSIONS The postoperative ventilatory function in patients with COPD who had lower or middle-lower lobectomies was better preserved than predicted.

Serum endostatin correlates with progression and prognosis of non-small cell lung cancer

The relationship between non-small cell lung cancer and platelet counts, serum levels of vascular endothelial growth factor (VEGF) and endostatin, is unclear. Platelet counts and serum VEGF and endostatin levels were measured preoperatively in 99 patients with non-small cell lung cancer, and the relationship between these factors and clinicopathological features, including prognosis, was examined. Mean serum VEGF level was slightly higher in patients than in healthy subjects (P=0.23). Mean serum endostatin level was 42.4+/-40.4 ng/ml in patients compared to 16.3+/-10.3 ng/ml in healthy subjects (P=0.0003). Serum endostatin levels were significantly higher in patients with involvement greater than T2 or stage IB, compared to other patients. Platelet count and serum endostatin level greater than the median were associated with poor prognosis. Our results suggested that platelet count and serum endostatin level may be useful markers for non-small cell lung cancer.

Correlation between endobronchial ultrasonography (EBUS) images and histologic findings in normal and tumor-invaded bronchial wall

The aim of this study was to examine the ability of endobronchial ultrasonography (EBUS) to image the bronchial wall structure in order to assess the depth of bronchial tumor invasion. Sixty-one patients who underwent lobectomy, pneumonectomy or forceps biopsy were included in this study. In 21 patients with bronchoscopically visible bronchial malignant tumors, EBUS was performed during bronchoscopy. In the remaining 40 patients, ultrasonography was performed on the resected specimens. The EBUS findings obtained using thin ultrasonic probes (20 MHz radial scanner) were compared with the macroscopic and histologic findings of the corresponding areas in the resected specimens. When the bronchial walls were imaged while immersed in normal saline, six ultrasonically distinct layers were detected in the cartilaginous and membranous portions. A similar wall structure was imaged when EBUS was performed during bronchoscopy using a latex balloon sheath. The image of the lamina propria and submucosa was occasionally compressed and mixed with a balloon echo due to the latex balloon sheath, whereas the cartilage layer was always distinctly imaged. A good correlation was observed between the EBUS-determined cartilage thickness and the actual histologic measurement, as measured with vernier calipers. Malignant tissues were imaged as hypoechoic areas, and tumor invasion of the cartilage layer was clearly detected. In conclusion, using high-resolution (20 MHz) ultrasonic probes, the bronchial wall structure could be imaged as six distinct layers. The cartilage layer was easily identified and could be used as a reference to evaluate the rest of the bronchial wall structure.

Pulmonary large cell carcinomas with neuroendocrine features are high-grade neuroendocrine tumors

BACKGROUND In 1999, the World Health Organization (WHO) categorized large cell carcinoma with neuroendocrine features as variants of large cell carcinoma and reclassified neuroendocrine lung tumors, especially typical and atypical carcinoid tumors. However, to date, the clinical relationship between these categories of neuroendocrine lung tumors has not been clearly defined. METHODS We analyzed 133 cases of neuroendocrine tumors from primary lung carcinoma cases surgically resected. Using electron microscopy and immunohistochemical staining, we classified these cases as typical carcinoid (TC), atypical carcinoid (AC), large cell carcinoma with neuroendocrine features (LCNF), or small cell lung carcinoma (SCLC) based upon the WHO classification. RESULTS TC and AC tumors were not related to smoking (p < 0.001) and, unlike LCNF, were found in younger patients (p < 0.001) without a male predominance (p < 0.001). Multivariate analysis revealed that LCNF predicted poorer overall and disease-free survivals comparable with SCLC (overall survival, p = 0.019, hazards ratio, 6.34; disease-free survival, p = 0.007, hazards ratio, 8.19). CONCLUSIONS The prognoses of LCNF are comparable with those of SCLC, and LCNF should be classified as high-grade neuroendocrine tumors.

Video-assisted thoracoscopic surgery does not deteriorate postoperative pulmonary gas exchange in spontaneous pneumothorax patients

Objectives: Video-assisted thoracoscopic surgery (VATS) is generally recognized as a less invasive method than thoracotomy. However, the influence of VATS on postoperative pulmonary gas exchange has yet to be evaluated. Methods: Thirty eight patients with spontaneous pneumothorax were randomized into bullectomy by VATS (na 20) or axillary thoracotomy (na 18). Gas exchange was assessed by using hot wire mass spectrometer, and blood gas analysis preoperatively and postoperatively at 1, 3, 6, 12, 24, and 48 h and on days 4 and 6. Post operative pain control was managed by continuous epidural morphine injection and administration of diclofenac sodium orally or suppository. Postoperative atelectasis was assessed by daily chest roentgenograms. Results: VATS patients had continuously higher PaO2 than axillary thoracotomy at 12, 48 h and day 4 postoperatively (P , 0:05). Alveolar-arterial oxygen tension gradient in VATS patients was significantly less than that in patients with axillary thoracotomy from the 6th h throughout to the 4th day postoperatively (P , 0:01). Use of postoperative analgesics and the incidence of peripheral atelectasis were more frequent in patients with axillary thoracotomy. Conclusions: Bullectomy via VATS was less deleterious to pulmonary gas exchange. Axillary thoracotomy caused worsening of gas exchange postoperatively due to incisional pain, chest wall deformity, and peripheral atelectasis. q 1999 Elsevier Science B.V. All rights reserved.