S11: molecular pathology + overview of neoplasia

Question 1

Describe the key molecular tests that are performed on lung cancer

Answer 1

Bronchoscope – gets biopsy for diagnosis
Lung markers: EGRF, ALK, ROS1, KRAS & BRAF
Targeted treatments: gefitinib, crizotinib etc
Immunotherapy

Question 2

Describe lung marker EGFR

Answer 2

Mutated in ~60% of Asians
Mutations lead to activation of TK signalling pathway -> cell differentiation & proliferation
Specific drug treatment for this mutation: gefitinib

Question 3

Describe lung marker ALK

Answer 3

Commonly seen in young, never smoked
Mutation causes activation of downstream signals -> cell proliferation & survival etc
Specific drug treatment for this mutation: crizotinib

Question 4

Describe lung marker KRAS

Answer 4

25% lung adenocarcinomas
SMOKERS
No drugs available yet, clinical trials going on (many cancers harbour this mutation)

Question 5

Describe the key molecular tests that are performed on melanomas

Answer 5

Molecular markers: BRAF & NRAS
Target therapies – anti BRAF (tumour resistance can develop)
Immunotherapies – PDL1