Microanatomy 3 Respiratory Flashcards
what is it called when the epithelium change shape
mesoplasia
where does squamous cell carcinoma of the lung usually arise
- usually arises in the main bronchi and is associated with areas that have previously undergone squamous metaplasia
what can lung carcinoma be divided into
- small cell and non small cell carcinoma
what is more malignant small cell or non small cell carcinoma
small cell carcinoma
describe what small cell carcinoma tumours look. like
- small
- ovid
- densely packed and darkly stained tumour cells
- disseminated
how is small cell carcinoma treated
- systemic chemotherapy
how is non small cell carcinoma treated
- iti is more localised and usually treated by combinations of surgery and radiotherapy in the first instant
what is an important transcription factor for development of the lung
- thyroid transcription factor
what is thyroid transcription factors use when it comes to cancer
- most primary tumours in the lung of this type will stain for this antigen
- this is used to differentiate primary from secondary tumours with similar characteristics
what is a granuloma in tb
macrophage lymphocyte fibroblast defensive reaction
- this is a characteristic of tuberculosis
- there is a central area of caseous necrosis surrounded by epithelia macrophages
- some of these macrophages fuse and form multinucleate langhans giant cells
- the caseous material contains mycobacteria which can only be visualised with special stains
- peripheral to macrophages there is a rim of lymphocytes
- in the lymphocyte layer of the tubercle fibroblasts are stimulated to lay down collagen in the extracellular matrix acting to wall off the tubercle
what is the resulting lesion called when a successful macrophage lymphocyte fibroblast defensive reaction occurs
- fibrocaseous tubercular nodule
when does tuberculous brnochopneumonia occur
- this occurs when the mycobacterium tuberculosis bacilli are released into the bronchi and gravitate to lower parts of the conducting airways
- through he destruction of the bronchiolar walls they can gain entry into the surrounding peribronchial lung tissue
- numerous tubercles may form and merge thus destroying large areas of lung tissue
describe primary TB
- this is when small lesions show restriction to the sub pleural area in the mid-zone of the lung and the draining hilarity lymph nodes
- gohn focus
describe what happens in post primary or secondary TB
- there is a focus of apical often bilateral lesions which occurs in the lungs
- ashman focus
describe what Millary tb is
- this occurs with the spread of the bacilli via the bloodstream to many locations and can occur in the lung and many other organs
why is normal lung a dark colour
- the normal lung is dark colour due to its blood content and the carbon which becomes trapped in interstitial macrophages
what type of defence cell is usually found in alveolar spaces
neutrophil
