Unfair diagnosis - Lung cancer pathology

Question 1

LUNG CANCER DIAGNOSIS

i) what is the first imaging method that should be requested?
ii) if a mass is seen on imaging - what should be looked at next?
iii) what does radical treatment depend on?
iv) give two examples of further investigations (one imaging and one biopsy)

Answer 1

i) CXR then chest CT
ii) look at mediastinal nodes - are they enlarged?
iii) radical treatment depends on nodal status
iv) can go on to do endobronchial US and/or transbronchial needle aspiration

Question 2

BIOPSY AND STAGING

i) what is stage defined as?
ii) which staging criteria is used for lung cancer?
iii) the combination of which two procedures can be used to sample the tumour?

Answer 2

i) stage = anatomical extent of a neoplasm
ii) TNM staging
iii) use endobronchial US to guide transbronchial needle aspiration

Question 3

LUNG NEOPLASIA

i) which main group makes up 75-85% of lung cancers?
ii) what is the most common histological subtype?
iii) which type are neurendocrine tumours and which are not?
iv) name a type of lung cancer that originates from the pleural
v) which tumour looks like small cell but is not?
vi) which type of carcinoma has cells that make keratin/shows desomosomes?

Answer 3

i) non small cell lung carcinoma = 75-85%
ii) adenocarcinomas are the most common (epithelial origin)
iii) non small cell are not neurendo and small cell are neuroendo tumours
iv) mesothelioma originate from the pleura and are non small cell
v) large cell carcinoma looks like small cell but is non small cell
vi) squamous cell carcinoma makes keratin / shows desmosomes

Question 4

ADENOCARCINOMA

i) which location is it most commonly found in?
ii) name two types of cells found within it
iii) name three markers it may be positive for?
iv) name four molecular markers that may be tested to see if it is lung cancer primary?
v) which type of tumour may this mimic? why?

Answer 4

i) usually found peripherally in the lung
ii) find columnar/glandular cells
iii) positive for TTF1, MOC31, BerEP4
iv) molec markers - EGFR, ALK, PDL1, ROS1
v) can mimic mesothelioma as it can invade the pleura and cause it to thicken

Question 5

BONE METASTASIS

i) name four tumour types that are likely to travel to the bone
ii) name three cancer types that like to travel everywhere
iii) what is the primary bony location of mets? name three others?
iv) what injury are people predisposed to if they have bony mets?

Answer 5

i) lung, breast, prostate, ovary
ii) melanoma, kidney, thyroid
iii) spine is most common, then pelvis, femur, humerus, ribs
iv) bony mets - predispose to pathological fractures as mechanically unstable

Question 6

SQUAMOUS CELL CARCINOMA

i) where is it usually anatomically located in the lung? what structure are they often close to?
ii) name two defining features of SCC on histology
iii) name four associated proteins
iv) what cells are characteristically seen on micro in squamous tissue?
v) why are these tumours predisposed to bleeding?

Answer 6

i) usually located centrally close to the hilum
ii) SCC = keritinisation & desmosomes
iii) P40, P63, CK5, CK6
iv) see eosinophils in squamous tissue
v) SCC = cavitation and central necrosis > bleed

Question 7

SMALL CELL/NEUROENDOCRINE CARCINOMA

i) what colour is seen on micro? why?
ii) name one other charac feature seen microscopically that is charac of NE tumours
iii) name three NE markers
iv) name a general lung tumour marker
v) if a tumour is P40, P63 and CK5/6 neg - is it likely to be NE?

Answer 7

i) blue/purple cells as very cellular
ii) NE tumours - see smudging
iii) NE markers - CD56, chromogranin and synaptophysin
iv) general lung tumour marker - TTF-1
v) P40/63 and CK5/6 are markers for adenocarcinoma - so if negative then it is likely to be NE

Question 8

PLEURAL EFFUSION

i) is this a adverse prognostic factor?
ii) name three characterstics that may be seen in an aspirate on micro if there are malignant cells?

Answer 8

i) yes - may indicate progression of disease
ii) on micro - see visible mitoses, variable nuclear size, large cells, generally very cellular

Question 9

MESOTHELIOMA

i) where does it originate?
ii) which two markers will it be positive for that are not expressed in other lung tumours?
iii) name four markers it may be negative for?
iv) what is it associated with?
v) what may be seen macroscopically? what molecule does it deposit?

Answer 9

i) originates in the pleura
ii) positive for WT1 & calretinin
iii) neg for TTF1, MOC31, napsin, P40
iv) associated with asbestos exposure
v) macro - see thickened pleura due to collagen deposits made by the tumour

Question 10

MOLECULAR LUNG PATHOLOGY

i) name four molecular markers that may be assessed
ii) name a technique this can be done by

Answer 10

i) ALK, EGFR, PDL1, ROS1
ii) IHC

Question 11

METS TO THE LUNGS

i) name four characteristics of lung mets
ii) how is the primary tumour elucidated? name four cancer types that may spread to the lung?

Answer 11

i) multiple, bilateral, sharply outlined, rapid growing, necrotic

ii) find the primary by looking at morphol/immunopheno to find primary
- colon, breast, prostate, melanoma