Tumours of the lung

Question 1

What are the key epidemiological features of Adenocarcinoma?

Answer 1

Most common primary lung cancer in women.
Most common lung cancer in never-smokers.
Typically located peripherally in the lung.

Question 2

What genetic mutation is associated with Adenocarcinoma?

Answer 2

EGFR mutations

Question 3

What are the microscopic and histologic features of Adenocarcinoma?

Answer 3

May be preceded by Atypical Adenomatous Hyperplasia.
Histologic variants:
Acinar
Papillary
Solid with mucous formation
Bronchiolo-Alveolar (lepidic growth along pre-existing alveolar walls).

Question 4

What is the synonym for Small Cell Lung Carcinoma?

Answer 4

Oat cell carcinoma

Question 5

Localisation of small cell lung carcinoma?

Answer 5

Peri-hilar localization.

Question 6

What are the macro-/microscopic features of Small Cell Lung Carcinoma?

Answer 6

High Nucleus to Cytoplasmic (N:C) ratio.
Neuroendocrine features.
Immunopositivity for Synaptophysin and Chromogranin.

Question 7

Why is Large Cell Carcinoma a diagnosis of exclusion?

Answer 7

Poorly differentiated tumours.
No evidence of squamous or glandular differentiation.
Does not meet criteria for Small Cell Carcinoma.

Question 8

What are common metastatic sites of Large Cell Carcinoma?

Answer 8

Hilar lymph nodes.
Adrenal gland (50% of cases).
Liver (30% of cases).
Brain (20% of cases).

Question 9

What are the primary cancers that metastasize to the lungs?

Answer 9

Breast cancer, colon cancer, and renal cell carcinoma.

Question 10

What are the common sites of lung metastasis?

Answer 10

Lung parenchyma.
Pleura and pleural space (can cause malignant effusions).
Lymphatics

Question 11

What is the main symptom of metastatic cancer to the lungs?

Answer 11

Dyspnoea

Question 12

What is the most common fatal cancer in both men and women?

Answer 12

Lung cancer

Question 13

What percentage of cancer deaths are caused by lung cancer in men and women?

Answer 13

30% M
25% F

Question 14

What is the peak incidence age range for lung cancer?

Answer 14

55–65 years.

Question 15

What is the leading cause of lung cancer?

Answer 15

Cigarette smoking (85–90% of cases).

Question 16

Which lung cancer types are most common in smokers?

Answer 16

Small Cell and Squamous Cell Carcinomas

Question 17

What type of lung cancer is more frequent in never-smokers, and in which gender is it more common?

Answer 17

Adenocarcinoma; more common in women.

Question 18

Name other risk factors for lung cancer apart from smoking.

Answer 18

Radiation (e.g., radium and uranium workers).
Asbestos exposure.
Exposure to certain metals (chromium, cadmium, beryllium, arsenic, nickel).

Question 19

What oncogenes and tumour suppressor genes are associated with lung cancer?

Answer 19

Oncogenes: KRAS, MYC, HER-2/neu, BCL-2, EGFR.
Tumour suppressor genes: p53, RB1, p16.

Question 20

What are the common symptoms of lung cancer?

Answer 20

Cough.
Haemoptysis.
Bronchial obstruction → Atelectasis and Pneumonitis.
Bloody pleural effusion.

Question 21

What is Superior Vena Cava Syndrome, and what causes it?

Answer 21

Compression or invasion of the Superior Vena Cava.
Causes facial swelling, cyanosis, and dilated veins in the head, neck, and upper extremities.

Question 22

What paraneoplastic endocrine syndromes are associated with lung cancer?

Answer 22

Small Cell Carcinoma:
ACTH-like activity.
Syndrome of Inappropriate Antidiuretic Hormone (SIADH).
Squamous Cell Carcinoma:
Parathyroid-like activity.

Question 23

What is a Pancoast tumour, and what syndrome is associated with it?

Answer 23

A tumour involving the lung’s apex.
Ass w Horner Syndrome (ptosis, miosis, anhidrosis) due to cervical sympathetic plexus involvement.

Question 24

Which type of lung cancer is generally not indicated for surgical intervention?

Answer 24

Small cell carcinoma

Question 25

Which types of lung cancer may be treated with surgery?

Answer 25

Non-Small Cell Carcinoma (NSCLC)

Question 26

Arrange the types of lung carcinoma in decreasing order of incidence.

Answer 26

Adenocarcinoma. Squamous Cell Carcinoma. Small Cell Lung Carcinoma. Large Cell Carcinoma. Bronchial Carcinoid.

Question 27

What is a papilloma?

Answer 27

Benign tumour of the lung

Question 28

How does the occurrence of papillomas differ between children and adults?

Answer 28

Multiple papillomas: Seen in children and associated with HPV. Solitary papillomas: Occur in middle to advanced age, not associated with HPV.

Question 29

What are the macroscopic findings of a papilloma?

Answer 29

Mucosal protrusions. Pedunculated lesions. Lobular pattern

Question 30

What are the microscopic findings in papilloma?

Answer 30

Fibro-vascular stalk. Squamous epithelium without atypia or mitosis.

Question 31

What is another name for a solitary pulmonary nodule?

Answer 31

Coin lesion

Question 32

How is a solitary pulmonary nodule characterized on a chest X-ray?

Answer 32

Discrete, well-marginated, rounded opacity of ≤3 cm in diameter. Completely surrounded by lung parenchyma. No relation to the hilum or mediastinum. No association with adenopathy, atelectasis, or pleural effusion.

Question 33

What is the risk of malignancy for a coin lesion in individuals under 35 years old?

Answer 33

1%

Question 34

What is the risk of malignancy for a coin lesion in individuals over 50 years old?

Answer 34

50-60%

Question 35

What are common causes of a solitary pulmonary nodule?

Answer 35

Granulomas (e.g., tuberculosis, histoplasmosis). Malignancy (primary cancer). Bronchial (chondroid) hamartoma.

Question 36

What is a synonym for a hamartoma?

Answer 36

Adenochondroma

Question 37

What is the most common benign lesion of the lung?

Answer 37

Hamartoma

Question 38

How does a hamartoma appear on imaging?

Answer 38

As a peripheral, round, or lobulated opacity.

Question 39

What is the typical size of a hamartoma?

Answer 39

3-4cm

Question 40

How do endo-bronchial hamartomas appear macroscopically?

Answer 40

Sessile or pedunculated.

Question 41

How do parenchymal hamartomas appear macroscopically?

Answer 41

Sub-pleural with cystic foci.

Question 42

What is the appearance of a hamartoma’s cut surface?

Answer 42

Grey or yellow (in case of fat presence).

Question 43

What connective tissue is most commonly found in a hamartoma?

Answer 43

Cartilage.

Question 44

How are epithelial clefts in a hamartoma lined?

Answer 44

By ciliated columnar epithelium or non-ciliated epithelium.

Question 45

What intersects the nodules of connective tissue in a hamartoma?

Answer 45

Epithelial clefts

Question 46

What is the primary population affected by squamous cell carcinoma of the lung?

Answer 46

Almost exclusively in smokers.

Question 47

Where is squamous cell carcinoma typically located?

Answer 47

Centrally in the lung.

Question 48

What are the differentiation levels observed in squamous cell carcinoma?

Answer 48

Tumours can range from well to poorly differentiated.

Question 49

What lesion often precedes squamous cell carcinoma?

Answer 49

Squamous Dysplasia.

Question 50

What type of tumour are bronchial carcinoids classified as?

Answer 50

Broncho-pulmonary neuroendocrine tumours (NETs).

Question 51

What is the incidence of bronchial carcinoids among primary lung tumours?

Answer 51

1-5% of all primary lung tumours.

Question 52

From which cells do bronchial carcinoids originate?

Answer 52

Normal neuroendocrine components of bronchial epithelium.

Question 53

What are the two subtypes of bronchial carcinoids?

Answer 53

Typical carcinoids and atypical carcinoids.

Question 54

What genetic abnormalities are seen in atypical carcinoids?

Answer 54

p53 mutations & abnormalities in BCL-2 and BAX expression.

Question 55

Describe the typical macroscopic appearance of bronchial carcinoids.

Answer 55

Tumour growth in the form of a finger-like or spherical polypoid mass projecting into the bronchial lumen, often covered by intact mucosa.

Question 56

What is a “collar-button” lesion in bronchial carcinoids?

Answer 56

A lesion where the tumour penetrates the bronchial wall to spread into peri-bronchial tissue.

Question 57

What are the growth patterns seen in bronchial carcinoids microscopically?

Answer 57

Solid, trabecular, gyriform, or glandular growth patterns.

Question 58

What are key microscopic features of bronchial carcinoid cells?

Answer 58

Uniform round nuclei, salt-and-pepper chromatin, moderate eosinophilic cytoplasm, & delicate fibrovascular stroma.

Question 59

Name immunohistochemistry markers positive in bronchial carcinoids.

Answer 59

Serotonin, Neuron-Specific Enolase (NSE), & Calcitonin.

Question 60

What is the mitotic rate in typical carcinoids?

Answer 60

<2 mitoses per 10 High Power Fields (HPF).

Question 61

Do typical carcinoids show necrosis or metastatic potential?

Answer 61

No, they lack necrosis and have no metastatic potential.

Question 62

What is the prognosis for typical carcinoids?

Answer 62

Excellent; 5-year survival rate of 90%.

Question 63

What features distinguish atypical carcinoids from typical carcinoids?

Answer 63

Increased pleomorphism, cytologic atypia, prominent nucleoli, 2-10 mitoses per 10 HPF, and presence of necrosis.

Question 64

What are common symptoms caused by the intraluminal growth of bronchial carcinoids?

Answer 64

Persistent cough, haemoptysis, secondary infections, bronchiectasis, emphysema, & atelectasis.

Question 65

What is carcinoid syndrome, and what symptoms does it include?

Answer 65

A syndrome caused by secretory activity, including intermittent attacks of diarrhoea, flushing, and cyanosis.