1. Chest p56-63 (Lung Cancer, Other Tumours)

Question 1

Solitary pulmonary nodule - definition (3)

Answer 1

Round or oval lesion <3cm in diameter (>3cm = mass).
Surrounded by normal lung parenchyma.
No associated adenopathy or pleural effusion.

Question 2

Classic benign calcification patterns (4)

Answer 2

Solid/diffuse.
Laminated.
Central.
Popcorn.

Question 3

Benign pulmonary nodule features (3)

Answer 3

Presence of fat.
Rapid doubling time (<1 month).
Slow doubling time (>16 months)

Question 4

Suspicious pulmonary nodule features (3)

Answer 4

Spiculated margins (corona Radiata sign).
Air bronchograms through the nodule (usually adenocarcinoma in situ).
Part solid/part ground glass lesions.

Question 5

Solid vs ground glass nodules - suspicion (3)

Answer 5

Part solid/part ground glass is most sus.
Only ground glass is intermediate.
Totally solid is least sus.

Question 6

when to use PET for SPNs

Answer 6

Can be used for SPNs >1cm.

Question 7

Hot on PET - DDx (2)

Answer 7

Cancer is supposed to be hot (SUV > 2.5).
Infectious or granulomatous nodules can also be hot.

Question 8

Ground glass nodules - PET findings (2)

Answer 8

Cold suggests cancer.
Hot suggests infection.

Question 9

Lung cancer risk factors (5)

Answer 9

Being >30YO,
Exposure to arsenic, nickel, asbestos, chromium, beryllium, radon),
Lung fibrosis,
COPD,
FHx

Question 10

Lung cancer - Types (4)

Answer 10

Squamous,
Small cell,
Large cell,
Adenocarcinoma

Question 11

Squamous cell Ca - features (5)

Answer 11

Usually centrally located.
Strong smoking association.
Cavitation is common.
Ectopic PTH production.
Good prognosis, late to metastasize

Question 12

Small cell Ca - features (5)

Answer 12

Usually central (common near main/lobar bronchi).
May only get central lymphadenopathy.
Paraneoplastic syndromes - SIADH and ectopic ACTH.
Poor prognosis.
Lambert Eaton - proximal weakness due to abnormal acetylcholine release at NMJ

Question 13

Large cell Ca - features (2)

Answer 13

Peripheral and large (>4cm).
Poor prognosis.

Question 14

Adenocarcinoma - features (3)

Answer 14

Usually peripheral, often upper lobes.
Commonest subtype and commonest to present as solitary pulmonary nodule.
Associated with lung fibrosis.

Question 15

BAC (Broncho-Alveolar Carcinoma) - definition

Answer 15

Subtype of adenocarcinoma

Question 16

Atypical adenomatous hyperplasia of the lung (AAH) - definition

Answer 16

Precursor to Adenocarcinoma of lung

Question 17

Adenocarcinoma in Situ (ACIS) - features (2)

Answer 17

<3cm.
Multiple subtypes, commonest is non-mucinous.

Question 18

Minimally invasive adenocarcinoma (MIA) (5)

Answer 18

<3cm with <5mm of stromal invasion (>5mm = lepidic predominant adenocarcinoma).
Usually ground glass.
Usually COLD on pet.
Fried egg sign (ground glass around nodule).
Pseudocavitation (bubble like lucencies).

Question 19

Part solid nodules - malignancy predictor

Answer 19

Larger the solid part, the more likely to be malignant.

Question 20

Staging threshold for unresectable lung cancer

Answer 20

3B (Implies N3 or T4 disease)

Question 21

Lung cancer staging - multicentric tumours (3)

Answer 21

T3 - 2 lesions in same lobe
T4 - 2 lesions in different lobes (same lung)
M1a - 2 lesions in different lungs

Question 22

Non-resectable features of lung Ca (4)

Answer 22

Supraclavicular or Scalene nodes.
Contralateral mediastinal or hilar nodes.
Tumour in same lung but different lobes.
Malignant pleural effusion.

Question 23

Radiation changes - features (3)

Answer 23

Varied appearance, based on volume of lung involved, time involved and whether chemo also given.
Early (1-3 months): Homogenous or patchy ground glass opacities.
Late: Dense consolidation, traction bronchiectasis and volume loss

Question 24

Bronchopulmonary fistula - features (4)

Answer 24

Uncommon complication of pneumonectomy.
Normally: Empty space will fill with fluid.
Fistula: Empty space fills with air over time.
Can confirm with xenon NM test, shows xenon in the pneumonectomy space.

Question 25

Mets to the lungs - types (3)

Answer 25

Direct invasion, Haematogenous, Lymphangetic Carcinomatosis (LC)

Question 26

Direct invasion mets - sources (4)

Answer 26

Cancer of the mediastinum, pleura or chest wall. Commonly oesophageal carcinoma, lymphoma or malignant germ cell tumour. Rarely mets to the pleura which directly invade lung. Even rarer - mesothelioma invading the lung.

Question 27

Haematogenous mets - features (4)

Answer 27

Tends to be multiple, random distribution, favouring lower lobes. Nodules smoother than primary neoplasm. Squamous mets can cavitate. Cannonball mets typically from renal cell or choriocarcinoma (testis)

Question 28

Haematogenous mets - sources (5)

Answer 28

Breast, Kidney, Thyroid, Colon, Head and neck squamous Ca.

Question 29

Feeding vessel sign (2)

Answer 29

Prominent vessel heading into a nodule. Suggests haematogenous origin. Either due to mets or septic emboli.

Question 30

Lymphagetic carcinomatosis (LC) - sources (5)

Answer 30

Commonest is bronchogenic carcinoma invading lymphatics. Non-lung common causes include: - Breast - Stomach - Pancreas - Prostate

Question 31

Lymphangetic carcinomatosis (LC) - features (2)

Answer 31

Nodular thickening of interlobular septa and sub-pleural interstitium. Thickening does NOT distort the pulmonary lobule, unlike fibrosis.

Question 32

Carcinoid - classification (4)

Answer 32

By distribution: - peripheral pulmonary - bronchial By histologic type: - typical - atypical

Question 33

Typical carcinoid - trivia (2)

Answer 33

Slow growing, locally invasive (10% met to nodes). No smoking association.

Question 34

Typical carcinoid - features (5)

Answer 34

Occur centrally within a bronchus and cause obstructive symptoms. Can cause haemoptysis, as they're highly vascular. Localised by Octreotide scan. Pulmonary tumours cause carcinoid syndrome w/flushing. Valvular degeneration occurs on left side (GI carcinoid tumours cause right sided valve degeneration)

Question 35

Atypical carcinoids (2)

Answer 35

Rarer, seen in older people. More likely to be a mass.

Question 36

Adenoid cystic (cylindroma) (3)

Answer 36

Commonest bronchial gland tumour. NOT associated with smoking. Usually main or lobar bronchus.

Question 37

Pulmonary lymphoma - types (4)

Answer 37

Primary, Secondary, PTLD, AIDS related.

Question 38

Pulmonary lymphoma - imaging (3)

Answer 38

Radiographic pattern varies. Lymphangitic spread (uncommon), Perihilar airspace opacities, Mediastinal adenopathy

Question 39

Primary pulmonary lymphoma - features (3)

Answer 39

Rare, usually non-hodgkin. Defined as lack of extrathoracic involvement for 3 months. 80% are low grade MALToma

Question 40

Secondary pulmonary lymphoma - features (4)

Answer 40

More common than primary. Pulmonary involvement of systemic lymphoma. NHL is more common than HL (80-90% lymphoma vs 10-20%) But NHL is less likely to involve the lungs. (45% intrathoracic, 25% parenchymal disease, vs 85% intrathoracic and 40% parenchymal) HL affects nodes and parenchyma, NHL can just affects parenchyma.

Question 41

PTLD (Post transplant lung disease) - features (4)

Answer 41

Usually within a year of solid organ or stem cell transplant. Late presentations (>1 year) are more agressive. B Cell lymphoma, with relationship with EB virus. Can get nodal and extra-nodal disease.

Question 42

PTLD - imaging (4)

Answer 42

Typically: Well defined pulmonary nodules/mass, Patchy airspace consolidation, Halo sign and interlobular septal thickening

Question 43

AIDS Related Pulmonary Lymphoma (ARL) - Features (4)

Answer 43

Second most common lung tumour in AIDS (behind Kaposi), Almost all high grade NHL. Relationship with EBV. Seen in CD4 <100.

Question 44

Aids related lymphoma- imaging (2)

Answer 44

Commonest: Multiple, peripheral nodules ranging 1-5cm. Extranodal locations are common (CNS, bone marrow, lung, liver, bowel)

Question 45

AIDS pt with lung nodules, pleural effusion and lymphadenopathy

Answer 45

Lymphoma

Question 46

Kaposi sarcoma - imaging (3)

Answer 46

Favours tracheobronchial mucosa and perihilar lung. Flame shaped. Bloody pleural effusion is common (50%)

Question 47

Kaposi sarcoma - trivia (5)

Answer 47

Commonest lung tumour in AIDS (requires CD4 <200), Most common hepatic neoplasm in AIDS, Buzzword - flame shaped opacities. Slow growth & asymptomatic, despite lungs looking terrible. Thallium positive, gallium negative.

Question 48

Hamartoma - imaging/features (4)

Answer 48

Macroscopic fat and popcorn calcifications. Usually incidental. Can cause problems if endobronchial (2%) Can be hot on PET, still benign.

Question 49

Hamartoma - trivia

Answer 49

Commonest benign lung mass.

Question 50

Thallium vs Gallium

Answer 50

Kaposi - Thallium positive, Gallium negative Lymphoma - Gallium positive, Thallium negative