Pathomorphological and endoscopic study of large bronchi in lung cancer

Abstract

Diffuse progressive atrophy of the bronchial epithelium and mucosa are the main changes detected in the biopsy specimens of large bronchi in lung cancer. Unstability of the bronchial epithelium in lung tumors (alternating atrophy, metaplasia, hyperplasia, and dysplasia) is described. Key Words: lung cancer; bronchial epithelium; bronchial biopsy; atrophy; instability phenomenonPathomorphosis of respiratory diseases [7,8] and many new lung diseases induced by ecological factors [3,4,6,11] are responsible for modification of pretumor processes. Reduced capacity to DNA repair and induced and spontaneous mutations facilitate malignant transformation of target cells [1]. Normal cell can be transformed into tumor cell not only due to gene mutations, but also due to epigenomic, or regulatory disorders [1,10]. Initial sign of central lung cancer is desquamation of bronchial epithelium (BE), one of the most important markers of its atrophy, denudation of the basal layer, and damage to basal cells, followed by their hyperplasia and metaplasia. Unstable tissue proliferation is believed to play an important role in this process [2]. Atrophic processes, highly prevalent in recent years, attracted our attention, because of the priority importance of early diagnosis of cancer.Our purpose was a pathomorphological and endoscopic study of the large bronchi in lung cancer for evaluating the role of structural changes in the airways in the morphogenesis of cancer of the respiratory organs. MATERIALS AND METHODSClinical, endoscopic, and pathomorphological studies were carried out in 250 patients with central and peripheral cancer. Among histological forms of lung cancer, squamous-cell (52%) and small-cell (30%) cancer and adenocarcinoma (15%) predominated, in the rest cases mixed forms were identified. Specimens of large bronchi were examined under light optic and electron microscopes and analyzed by autoradiography. For light microscopy the fragments were fixed in 10% neutral formalin and treated routinely. Paraffin sections were stained with hematoxylin and eosin with Pearl's reaction, elastic fibers were stained by the method of Van-Gieson followed by Weigert's resorcin-fucsin poststaining, and periodic acid Schiff reaction was performed.For electron-microscopy, small fragments (no more than 1 mm 3) were fixed in 4% paraformaldehyde and 1% OsO 4. After standard treatment for electron microscopy, the tissue was embedded in epon-araldite. Scmithin sections were stained with 1% azur II and Schiff reagent. Ultrathin sections after double-contrasting were examined under a JEM 1010 electron microscope at accelerating voltage of 80 kV.

Invasive Procedures withQuestionable Indications used in Russia: Recent History

“…Endoscopic monitoring of the therapy efficiency has been applied in pulmonary Tb with non-specific bronchial lesions, also recently [147,158]. Bronchial biopsy specimens were used for research, often being suboptimal quality [2], descriptions sometimes being stereotype, morphometric and other quantitative indices changing according to the concept [2,86,159,160]. Some histological descriptions were doubtful e.g.…”

“…In some bronchial biopsy studies, scanning electron microscopy was the only morphological method used [139]. Biopsies were taken for research from large bronchi of patients with known lung cancer, whereas quality of histological and ultrastructural images was low (Figure 1) [159], which means additional discomfort with no impact on the therapy. Another example: lavage fluid collected by Bs from patients with lung cancer and from those with Tb (including focal forms, tuberculoma etc.)…”

On the endoscopic methods used in pediatrics with questionable indications

“…As mentioned above, bronchial biopsy specimens were used for research, whereas some morphological illustrations were suboptimal quality, descriptions being stereotype, morphometric and other quantitative indices uniformly improving after a medical or surgical asthma treatment [22] , [36] , [37] , [38] . Some morphological descriptions were doubtful e.g.…”

“…Bronchoscopy was used as a screening method in young (mean age 19.5 years) patients diagnosed with community-acquired pneumonia (1478 bronchoscopies in 977 patients), while the most frequent finding was mucopurulent bronchitis [40] . Biopsies were collected for research from large bronchi of patients with known lung cancer, whereas quality of histological and ultrastructural images was suboptimal [37] . Besides, gastrodoudenoscopy with biopsies used for research were applied in children with rheumatoid arthritis, dermatomyositis, scleroderma, systemic lupus erythematosus, respiratory and hepatobiliary diseases [40] , [41] , [42] , [43] , [44] , [45] , [46] .…”

Instability of bronchial epithelium in chronic pulmonary diseases

“…Thickness of the epithelium greatly varied, especially, in neoplastic processes. Atrophy and epithelial instability phenomenon are interpreted as morphological markers of ecological and oncological risk.Key Words: chronic pulmonary diseases; bronchial epithelium; atrophy; bronchial biopsy; radioautography; electron microscopy Atrophy is now a predominant phenotypical modification of the bronchial epithelium under conditions of chronic pulmonary diseases of different origin [4,8,9,11,13]. New types of structural reactions formed today reflect the interaction between the organism and adverse exo-and endogenous factors [3,[14][15][16].…”