Intrathoracic Malignancies

Question 1

What are the primary sites of intrathoracic malignancy?

Answer 1

Lung (carcinoma), Pleura (mesothelioma), Thymus and mediastinum.

Question 2

What are common secondary intrathoracic malignancy sources?

Answer 2

Lung and pleura metastases from breast, GI, ovarian cancers, or unknown primary.

Question 3

What percentage of primary lung malignancies are carcinomas?

Answer 3

> 90%.

Question 4

What is the leading cause of cancer mortality worldwide?

Answer 4

Lung carcinoma.

Question 5

What percentage of lung cancers are linked to smoking?

Answer 5

90%.

Question 6

What is the global annual death toll from smoking-related lung cancer?

Answer 6

Over 1 million.

Question 7

How does lung cancer risk change after smoking cessation?

Answer 7

Relative risk reduces to 1.6 after 15 years.

Question 8

What is the relative risk of passive smoking?

Answer 8

1.25 (equivalent to 1 cigarette per day).

Question 9

Name 3 carcinogens in cigarette smoke.

Answer 9

Polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines, polonium-210.

Question 10

Name 2 carcinogenic metals in cigarette smoke.

Answer 10

Arsenic, cadmium.

Question 11

What percentage of smokers develop lung cancer?

Answer 11

10–15%.

Question 12

Name 4 occupational carcinogens linked to lung cancer.

Answer 12

Asbestos, arsenic, radon, chromates.

Question 13

What is radon and how does it cause lung cancer?

Answer 13

A radioactive gas from soil/rocks; emits alpha particles after inhalation.

Question 14

Which UK region has the highest radon levels?

Answer 14

Cornwall.

Question 15

How does smoking interact with asbestos exposure?

Answer 15

Additive/synergistic effect — 55-fold increased risk when combined.

Question 16

What is a driver mutation?

Answer 16

A genetic alteration essential for tumor survival and progression.

Question 17

What mutations are common in adenocarcinoma of the lung?

Answer 17

EGFR (non-smokers), KRAS, BRAF (smokers), ALK, ROS1.

Question 18

What hallmark mutation is seen in small cell carcinoma?

Answer 18

RB1 inactivation.

Question 19

Name 4 common symptoms of lung carcinoma.

Answer 19

Cough, weight loss, haemoptysis, chest pain.

Question 20

What causes hoarseness in lung cancer patients?

Answer 20

Invasion of recurrent laryngeal nerve.

Question 21

What is Horner’s syndrome?

Answer 21

Miosis, ptosis, enophthalmos — due to sympathetic plexus invasion.

Question 22

What is Pancoast tumor?

Answer 22

Apical tumor causing Horner’s syndrome and ulnar nerve pain.

Question 23

Name 3 common metastasis sites of lung carcinoma.

Answer 23

Brain, liver, adrenal glands.

Question 24

What hormone causes hyponatraemia in lung cancer?

Answer 24

ADH (via paraneoplastic syndrome).

Question 25

What is Lambert-Eaton Myasthenic Syndrome?

Answer 25

Autoimmune muscle weakness due to antibodies against neuronal calcium channels.

Question 26

Name 3 imaging modalities used in lung cancer diagnosis.

Answer 26

Chest X-ray, CT, PET-CT.

Question 27

What bronchoscopy techniques help in cytological diagnosis?

Answer 27

BAL, brushing, EBUS-TBNA.

Question 28

What are the main histological types of lung carcinoma?

Answer 28

Adenocarcinoma, squamous cell carcinoma, large cell carcinoma, small cell carcinoma.

Question 29

What percentage of lung cancers are non-small cell types?

Answer 29

85%.

Question 30

Describe histology of small cell carcinoma.

Answer 30

Small blue cells, nuclear molding, high mitotic rate, neuroendocrine differentiation.

Question 31

What is TNM staging used for?

Answer 31

To classify the extent of cancer (Tumor size, Node involvement, Metastasis).

Question 32

Which lung cancer type often requires immediate treatment?

Answer 32

Small cell carcinoma.

Question 33

What is the 5-year survival for early-stage non-small cell carcinoma?

Answer 33

23–60%.

Question 34

What is the median survival for extensive small cell carcinoma?

Answer 34

9 months.

Question 35

Name 2 EGFR-TK inhibitors.

Answer 35

Erlotinib, gefitinib.

Question 36

What do PD-1/PD-L1 inhibitors do?

Answer 36

Prevent T-cell suppression, allowing immune attack on tumors.

Question 37

Give 2 immune checkpoint inhibitors used in lung cancer.

Answer 37

Nivolumab, pembrolizumab.

Question 38

What is the primary cause of mesothelioma?

Answer 38

Asbestos exposure (>90%).

Question 39

What type of asbestos is most carcinogenic?

Answer 39

Crocidolite (blue asbestos).

Question 40

What is the latent period between asbestos exposure and mesothelioma?

Answer 40

Up to 50 years.

Question 41

What is asbestosis?

Answer 41

Interstitial fibrosis of the lung due to asbestos.

Question 42

What gene mutations are found in mesothelioma?

Answer 42

NF2, BAP1, TP53.

Question 43

Name 3 symptoms of mesothelioma.

Answer 43

Dyspnoea, chest pain, pleural effusion.

Question 44

What imaging findings suggest mesothelioma?

Answer 44

Pleural thickening > 1 cm, effusion.

Question 45

How is mesothelioma confirmed histologically?

Answer 45

Pleural biopsy via thoracoscopy (VATS).

Question 46

Name 3 histological types of mesothelioma.

Answer 46

Epithelioid (60-80%), sarcomatoid (<10%), biphasic (10-15%).

Question 47

What is the prognosis of mesothelioma?

Answer 47

1-year survival ~50%; very few survive beyond 2 years.

Question 48

What is pleurodesis?

Answer 48

Instilling talc into pleural cavity to cause fibrosis and obliterate it.

Question 49

What compensation systems exist for mesothelioma?

Answer 49

Industrial Injuries Disablement Benefit (IIDB), civil legal claims.

Question 50

Why is a coroner's inquest relevant in mesothelioma?

Answer 50

Determines unnatural cause of death for compensation eligibility.