Lung Carcinoma

Question 1

What route of metastasis are lung cancers prone?

Answer 1

Lymphatics due to the extensive number of lymph vessels surrounding the bronchiole vascular bundles

Question 2

What can occur in transcoelmic spread of lung cancer?

Answer 2

Increased fluid production in the pleural cavity leading to pleural effusion

Question 3

What is lymphagitis carcinoma?

Answer 3

Lymphangitis carcinoma = thickening of the vessels and a characteristic spread through the lymphatics in the lungs only. Occurs with metastisis to the lungs or from primary lung tumor. Leads to severe SOB

Question 4

What are the main types of lung cancers?

Which are smoker’s more prone to?

Answer 4

Small cell carcinoma, large cell carcinoma, SCC and adenocarcinoma

Smokers = SCC and adenocarcinoma

Question 5

What is the dysplasia-carcinoma sequence for lung SCC?

Answer 5

Begins with goblet cell hyperplasia, sqamous metaplasia, dysplasia and then carcinoma in situ and invasion

Metaplasia occurs due to exposure to irritants i.e. smoke and dysplasia arises when mutation occurs i.e. carcinogens in smoke

Question 6

What are some differences in pathological features between SCC and adenocarcinoma of the lung?

Answer 6

They are typically pale masses arising in the bronchus
Adenocarcinomas more proximal and SCC more proximal bronchi
SCC are usually necrotic and form cavities
Both can lead to obstructive pneumonia, bronchiectasis or a collapsed lung

Question 7

How can tumour type be determined?

Answer 7

H&E from biopsy

Immunohistochemistry if can’t tell from H&E - staining for certain antigens/markers

Question 8

How can specific mutations allow targeted therapy?

Answer 8

Same cancer type has different mutations i.e. TP53, KRAS and STK11 most common in lung adenocarcinoma

Can determine the responsiveness to certain treatments

Specific treatments can used based on the mutation i.e. inhibition of specific growth factors or monoclonal Abs for specific receptors or proteins