Pathology

Question 1

what are the three types of tumours?

Answer 1

• 4 common smoking associated types
• neuroendocrine tumours
• bronchial gland tumours

Question 2

what are the 4 types of smoking associated?

Answer 2

• adenocarcinoma
  small cell
  large cell
  squamous

Question 3

what is the most common one?

Answer 3

adenocarcinoma- it is common in non-smokers too

Question 4

what does adenocarcinoma often cause on CXR/CT?

Answer 4

peripheral lesions

Question 5

how does adenocarcinoma arise?

Answer 5

from mucus secreting glandular cells

it metastasises widely

Question 6

how does squamous carcinoma arise?

Answer 6

from epithelial cells

Question 7

what are some characteristics of sqaumous carcinoma?

Answer 7

local, slow metastasis

hypercalcaemia

PTH

produces keratin pearls

Question 8

what problems are often related to squamous ?

Answer 8

bronchiectasis and obstructive pneumonia as the tumour is often centrally located

Question 9

how does small cell arise?

Answer 9

from APUD cells- these are A GROUP OF unrelated endocrine cells
they secrete ACTH

Question 10

where is small cell often located?

Answer 10

centrally

Question 11

on CXR/CT what may be seen with small cell?

Answer 11

hilar mass with extension onto lymph nodes

Question 12

what are some features of small cell

Answer 12

its hard to treat because of rapid metastasis

Question 13

what is seen on a slide for small cell?

Answer 13

not much cytoplasm and lots of nuclei. The nuclei look like lymphocytes so it can be confused with lymphoma

Question 14

what are some characteristics of large cell carcinoma?

Answer 14

pooorly differentiated

metastasis early on

Necrosis and haemorrhage are frequent and there may be acute and/or chronic inflammation. They form large necrotic masses

Question 15

what is shown on slides for large cell?

Answer 15

it consists of sheets and nests of large cells with prominent vesicular nuclei and nucleoli

The cell borders are easily vascularised.

Question 16

what may happen to the pleura in large cell?

Answer 16

the large necrotic masses frequently invade the overlying pleura and grow into adjacent structures

Question 17

what is the pathophysiology of bronchial tumours - i.e. tumours of the lung ?

Answer 17

1. squamous metaplasia
2. dysplasia
3. carcinoma in situ
4. invasive malignancy

Question 18

what happens in peripheral adenocarcinoma

Answer 18

spread of neoplastic cells along alveolar walls (bronchioalveolar carcinoma) without invading underlying stroma.

Question 19

what are some examples of other lung neoplasms?

Answer 19

carcinoid

bronchial gland neoplasms (tumours often seen in salivary glands)

Question 20

what are two bronchial gland neoplasms

Answer 20

• adenoid cystic carcinoma

- mucoepidermoid carcinoma

Question 21

what are carcinoid neoplasms?

Answer 21

neuroendocrine neoplasms of low grade malignancy and they tend to occur in younger patients

Question 22

what are the pleural neoplasia kinds?

Answer 22

benign tumours are rare

the primary malignant neoplasms - mesothelioma

the pleura is a very common site of invasion of lung carcinomas and metastatic cancers

Question 23

what would mesothelioma look like on CXR?

Answer 23

usually unilateral, starting as small nodules over the visceral pleura and extending to cover the entire lung

Question 24

which cancer has the worst and best prognosis ?

Answer 24

small cell is the worst

large cell worse than squamous or adenocarcinoma

squamous worse than adenocarcinoma

Question 25

why is classification important?

Answer 25

for treatment purposes - small cell known to be chemosensitive but with rapidly emerging resistance - surgery is the treatment in other types

Question 26

for which cancer is pemetrexed contraindicated?

Answer 26

squamous carcinoma

Question 27

why is classification also quite difficult?

Answer 27

because its hard to subtype tumours on small biopsies

Question 28

how is immunochemistry often used to help classify biopsies?

Answer 28

in adenocarcinoma - expresses TTF (thyroid transcription factor ) 1 small cell carcinoma expresses nuclear antigen p63 and high molecular weight cytokeratins

Question 29

what else is used to classify biopsies?

Answer 29

molecular genetic abnormalities

Question 30

what oncogenes and tumour suppressor genes are expressed in SCLC?

Answer 30

oncogenes- myc | tumour suppressor genes - p53, Rb, 3p

Question 31

what oncogenes and tumour suppressor genes are expressed in NSCLC?

Answer 31

oncogenes - myc, K-ras, her2 (neu) | tumour suppressor genes - p53, 1q, 3p, 9p, 11p, Rb

Question 32

Molecular pathology and targeted treatment - Adenocarcinoma

Answer 32

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 mutations seen almost exclusively in adenocarcinoma (esp. non-smokers and asian populations) these tumours respond to tyrosine kinase inhibitors (erlotinib) EML4-ALK fusion oncogene also identifies a target for specific drug treatment (crizotinib)

Question 33

how are tumours classified?

Answer 33

TNM scale

Question 34

what does T stand for?

Answer 34

primary tumour 

Question 35

what does N stand for?

Answer 35

regional nodes

Question 36

what does M stand for?

Answer 36

distant metastasis

Question 37

what markers are in stage 1 ?

Answer 37

- carcinoma insitu/ ≤3cm, in lobar or more distal airway/>3cm and >2cm distal to carina or any size if pleural involvement or obstructive pneumonitis extending to hilum, but not all the lung N0- None involved (after mediastinoscopy) M0- none

Question 38

what markers are in stage 2 ?

Answer 38

≤3cm, in lobar or more distal airway/>3cm and >2cm distal to carina or any size if pleural involvement or obstructive pneumonitis extending to hilum, but not all the lung N1 Peribronchial and/or ipsilateral hilum M0 none

Question 39

what are the markers in stage 3a?

Answer 39

Involves the chest wall, diaphragm, mediastinal pleura, pericardium, or 7cm diameter and nodules in same lobe n1- Peribronchial and/or ipsilateral hilum M0 or T1-3 N2 M0

Question 40

what are the markers in stage 3b?

Answer 40

T1-4 T1 ≤3cm, in lobar or more distal airway T2 >3cm and >2cm distal to carina or any size if pleural involvement or obstructive pneumonitis extending to hilum, but not all the lung T3 Involves the chest wall, diaphragm, mediastinal pleura, pericardium, or 7cm diameter and nodules in same lobe T4 Involves mediastinum, heart, great vessels, trachea, oesophagus, verte- bral body, carina, malignant effusion, or nodules in another lobe N3 Contralateral mediastinum or hilum, scalene, or supraclavicular M0