Regression of bronchial epithelial cancer in hamsters

Is there a relationship between the presence of lung mucosa preinvasive lesions and lung cancer incidence? Influence of tobacco consumption

Although studied for years, the nature of the relationships between tobacco consumption, bronchial preinvasive lesions and lung cancer are still not completely elucidated. Objectives were to determine the relationship between tobacco consumption and lung mucosa preinvasive and invasive lesions and to describe patients' evolution according to baseline characteristics.

METHODS

Bronchial biopsy specimens were taken at six predetermined sites in 156 males, current smokers, aged above 18 years. Relationships between smoking characteristics and preinvasive lesions indexes and between baseline characteristics and lung cancer occurrence during a prospective follow-up were examined.

RESULTS

Maximum grade was hyperplasia for 16.7% of patients, metaplasia 33.3%, dysplasia 25.0%, and carcinoma in situ 1.3%. For 23.7% of patients, all biopsies were considered normal. Preinvasive lesion indexes were related to smoking intensity (cigarettes/day). Lung cancer incidence during the follow-up was 19.9%. No association between severity of mucosa lesions at baseline and incidence of cancer during the follow-up period was observed.

CONCLUSION

The majority of smokers had mucosa lesions, but a relatively small number of them would have a cancer, and there was a poor correlation between severity of mucosalesions and incidence of cancer. Even if an evolution from preinvasive lesions to an invasive cancer is plausible and coherent with current concepts, this link does not appear strong enough to recommend the use of systematic classic endoscopy for targeting of a sub-group of higher risk smokers who would require a closer follow up.

Early lung cancer: methods for detection

Early detection and surgical resection are essential for the treatment of lung cancer. It would be ideal to be able to detect and treat preinvasive bronchial lesions, defined as dysplasia and carcinoma in situ before progressing to invasive cancer. Advanced airway-assessment techniques have opened an avenue for early detection and surveillance of endobronchial malignancy. This article reviews currently available advanced imaging techniques for early detection of lung cancer, including autofluorescence bronchoscopy, narrow-band imaging, high-magnification bronchovideoscopy, endobronchial ultrasonography, and optical coherence tomography. Also discussed are the more recently developed endocytoscopy system and confocal fluorescence microendoscopy, currently used only for research purposes.

A Pilot Study of Narrow-Band Imaging Compared to White Light Bronchoscopy for Evaluation of Normal Airways and Premalignant and Malignant Airways Disease

BACKGROUND

The objectives of this study were to characterize the appearance of normal, dysplastic, and frankly malignant airway lesion appearance under narrow-band imaging (NBI), and to determine if NBI, when used in conjunction with white light (WL) bronchoscopy, could improve detection of dysplasia and malignancy.

PATIENTS AND METHODS

This was a prospective, partially blinded study at a university teaching hospital. Bronchoscopy was performed on 22 patients with known or suspected bronchial dysplasia or malignancy. Full airway examination was performed first under WL bronchoscopy and then under NBI. Directed endobronchial biopsies of likely dysplastic, malignant, and normal (control) areas were then performed and sent for examination by a pathologist blinded to the gross description of the lesion. Pathology interpretations were then compared to the corresponding WL and NBI images.

RESULTS

There were one malignant and four dysplastic lesions in 22 patients detected by NBI when findings by WL imaging were considered normal. In cases when the WL appearance was abnormal, NBI did not improve the diagnostic yield. The increased rate of detection of dysplasia and malignancy by NBI was statistically significant (p = 0.005).

CONCLUSION

NBI identified dysplasia or malignancy that was not detected by WL inspection in 23% of subjects. Further studies are needed to determine the efficacy of NBI in detection of premalignant airways lesions in an at-risk population.

Cigarette smoking, preinvasive bronchial lesions, and autofluorescence bronchoscopy

STUDY OBJECTIVES

Autofluorescence bronchoscopy (AFB), when used as an adjunct to standard white light bronchoscopy (WLB), enhances the bronchoscopist's ability to localize small neoplastic lesions, especially intraepithelial lesions. The current study was undertaken in order to define the population in which the rate of detection is higher using AFB.

DESIGN AND PATIENTS

Two hundred forty-four consecutive patients, who were symptomatic smokers or patients who previously had been treated for lung cancer or head and neck cancers, underwent WLB and AFB. All patients with endoscopic abnormalities underwent biopsies. Data concerning smoking history were prospectively registered.

RESULTS

We report the prevalence of high-grade or invasive lesions at the time of examination. On a lesion-by-lesion analysis, 92 low-grade lesions, 42 high-grade lesions (ie, moderate dysplasia, severe dysplasia, and carcinoma in situ), and 39 invasive carcinomas were diagnosed. There was no effect of age, gender, and age at smoking initiation on the prevalence of preinvasive or invasive lesions. The 10 patients who previously had undergone surgery for lung cancer and exhibited high-grade preinvasive lesions had a history of carcinoma of the epidermoid histologic type (p = 0.01). These 10 patients displayed multiple lesions in the bronchial tree (mean No. of lesions, 1.8 per patient). In current smokers, the prevalence of high-grade or invasive lesions were both related to the number of pack-years smoking had occurred (p = 0.01) and to the duration of smoking (p = 0.01). In contrast, the prevalence of preinvasive lesions in former smokers was related to a history of epidermoid carcinoma.

CONCLUSIONS

AFB should be recommended in patients with a history of epidermoid carcinomas of the lung. Current smokers with a prolonged smoking history appear to comprise a population in which the rate of detection of preneoplastic lesions is high with AFB.

Long-term results of reoperations for recurrent angina with internal mammary artery versus saphenous vein grafts

OBJECTIVE

To evaluate the long term results of coronary reoperations for recurrent angina with internal mammary (thoracic) arteries versus vein grafts.

DESIGN

Inception cohort of 103 patients with a mean follow up of 7.1 years (range 1.0-11.6).

SETTING

Regional cardiothoracic centre.

PATIENTS

Among 103 consecutive patients, mean (SD) age 61.8 (9.7) years, who were reoperated for recurrent angina between January 1982 and December 1991, 53 patients had unilateral or bilateral internal mammary artery (IMA) grafting supplemented or not with saphenous vein (SV) grafts (group A), and 50 patients underwent reoperative coronary surgery using SV grafts only (group B). The two groups were comparable in terms of demographic and clinicopathological data.

MEASUREMENTS AND RESULTS

Operative mortality was 5.6% (95% confidence interval 4.6 to 6.6) for group A, and 10% (8.2 to 11.8) for group B (p > 0.05). Probability of freedom from new recurrence of angina was 86% at 5 and 10 years in group A, compared with 56% and 25% respectively in group B (p = 0.005). Freedom from cardiac events was estimated to be 81% at 5 and 10 years in group A, v 52% and 20% for group B, respectively. Actuarial survival was 95% v 93% at 3 years, 95% v 85% at 5 years, and 88% v 71% at 10 years after reoperation (p > 0.05).

CONCLUSIONS

The long term results of IMA are superior to SV grafts in terms of freedom from new recurrence of angina and other cardiac events. The IMA is thus the conduit of choice in coronary revascularisation.

Bronchial carcinogenesis in syngeneic hamsters

Endobronchial sustained release implants of carcinogen were placed in males (m) and females (f) of four varieties of syngeneic hamsters: BIOF1D; BIO87.20; BIO1.5; BIO15.16. The sequential progression of carcinogenesis that occurred was faster for 1.5m than for 1.5f (P = 0.01) and less rapid for 15.16m than for 87.20m and F1Dm (P < 0.05). Fewer invasive cancers occurred in 15.16m than in the other male varieties (P < 0.01), in 1.5m than in 87.20m (P < 0.05), and in 87.20f than in 87.20m (P < 0.05). Adenocarcinoma occurred with greater frequency in the 1.5 variety than in the F1D variety (P < 0.05). Significant variability in susceptibility, incidence, and types of invasive cancers formed exists, providing new opportunities for further study of bronchial carcinogenesis.