lung neoplasms: pathology

Question 1

What are the different types of lung neoplasms that occur?

Answer 1

Primary: benign (rare) malignant (very common)

Metastases (common)

Question 2

What are 6 risk factors for lung malignancy?

Answer 2

• smoking
• Asbestos
• nickel
• chromates
• radiation
• atmospheric pollution
• genetics

Question 3

What ectopic hormone production is produced by squamous cancer vs small cell cancer?

Answer 3

Squamous = PTH therefore can have hypercalcaemia (can also be caused by bony mets)
Small cell cancer = ACTH

Question 4

What are the four common smoking assoc. type of lung cancer? what 2 other tumours occur?

Answer 4

Smoking:
Adenocarcinoma (35%)
Squamous carcinoma (30%)
Small cell carcinoma (25%)
Large cell carcinoma (10%)

Other:

• neuroendocrine tumours
• bronchial gland tumours

Question 5

Which type of lung tumour has the worst survival time? which is the second worst?

Answer 5

• Small cell is worst: almost all dead in 1 year

- Large cell worse than squamous or adenocarcinoma

Question 6

What is the most simple classification of lung cancer?

Answer 6

Small cell lung cancer
vs
non-small cell lung cancer

Question 7

What is the treatment of choice for small cell vs non-small cell lung cancer?

Answer 7

• Small cell known to be chemosensitive

- surgery the treatment of choice in other type but ‘non small cell’ regimens have been developed in chemo/radiotherapy

Question 8

What is the difference between the immunohistochemistry in adenocarcinoma vs squamous cell carcinoma for the lung?

Answer 8

Adenocarcinoma expresses thyroid transcription factor 1 (TTF1)

SCC expresses nuclear antigen p63 and high molecular wt. cytokeratins

Question 9

Which types of lung tumours respond to tyrosine kinase inhibitors e.g. erlotinib?

Answer 9

Specific point mutations render the EGFR gene active in the absence of ligand (epidermal growth factor) binding
These mutations can be identified in DNA extracted from biopsy or cytology samples
Mutation seen almost exclusively in adenocarcinoma (esp. non-smokers and in Asian populations)
These tumours respond to tyrosine kinase inhibitors (erlotinib)
EML4-ALK fusion oncogene also identifies a target for specific drug treatment (crizotinib)

Question 10

Describe the progression of bronchial tumours?

Answer 10

Squamous metaplasia leads to dysplasia leads to carcinoma in situ leads to invasive malignancy

Question 11

What is metaplasia?

Answer 11

one differentiated cell type is replaced by another differentiated cell type

Question 12

what is dysplasia?

Answer 12

abnormal change in the cells characteristics often resulting in the presence of immature cells

Question 13

What does atypical adenomatous hyperplasia mean?

Answer 13

Spread of neoplastic cells along alveolar walls (bronchioloalveolar carcinoma)
True invasive adenocarcinoma
THIS PATTERN IS BECOMING COMMONER

Question 14

Where are small cell lung cancers usually located?

Answer 14

around the hilum/central

Question 15

Where are adenomas usually located in the lung?

Answer 15

More often found peripherally – therefore present late because they less likely to cause obstruction symptoms

Question 16

Where are large cell lung cancers usually located?

Answer 16

centrally

Question 17

How do squamous cell carcinomas usually present?

Answer 17

obstructive lesions of the bronchus

Question 18

Which type of lung tumour cavitates? what does this mean?

Answer 18

-squamous cell: part of the tumour undergoes necrosis