Squamous cell carcinoma

30% of lung cancer
Related to smoking
65% found in main, lobar, or segmental bronchi
Endobronchial mass
Bronchial obstruction
Infiltration of bronchial wall
Local invasion
Hilar mass
Atelectasis and consolidation common
30% solitary nodule or mass
Central necrosis and cavitation relatively common
Metastasis late
Relatively good prognosis

Right middle lobe syndrome

Most in child
Chronic inflammation
Congential heart disease
Asthma
Cystic fibrosis
Bronchopulmonary dysplasia
Obstructive lesion

Cause repeated pneumonia

Atelectasis

cause: tumor (most SCC), TB, sarcoidosis, Post operative atelectasis. Large left atrium.
Types:
Resorption - Obstruction
Relaxation - Passive, Pleural effusion, pneumothroax
Adhesive - ARDS (decrease in surfatant production)
Cicatricial - Lung fibrosis
ex. right middle lobe syndrome
Discoid atelectasis: Emoblus, Penumonia, Inadequate inspiration Carcinoma
Segmental atelectasis
Sign
Double lesion sign - RUL and RML collapse
Shifting granuloma sign
Golden's S sign - RUL
Juxtaphrenic peak - UL
Luftsichel sign - LUL - Apical cap
Falt waist sign - LLL
Comet-tail sign - Rounded
Rounded atelectasis - Posterior lower lobe. often free pleural effusion with inflammation