Natural History of Lung Cancer

General points:

• 5% of Lung Cancers are detected in asymptomatic phase (i.e.: good prognosis)

• 95% of Lung Cancers are detected in symptomatic phase (i.e.: poor prognosis, metastatic disease)

Modes of spread

Usually, carcinoma of the lung begins as an area of thickening or piling up of bronchial mucosa. Over time it appears warty and elevates/erodes the lining epithelium. From here a variety of pathways can be followed:

• fungate into bronchial lumen to produce intraluminal mass

• penetrate beneath the bronchial mucosa into the peribronchial tissue -->mediastinum

• grows within the parenchyma and produces a large intraparenchymal mass

These are all local lesions. Metastatic lesions include:

• lymphatic spread – involvement of mediastinal, supraclavicular, and cervical lymph nodes  lymphangitis carcinomatosa.

• Haematogenous spread

Category: Pathology Notes