Lung Cancer

Question 1

Causes of Lung cancer

Answer 1

Radiation therapy: Breast cancer and lymphoma patients
Environmental toxins: second-hand smoke, asbestos, radon, arsenic, chromium, nickel, and polycyclic aromatic hydrocarbons
Pulmonary fibrosis
Genetic factors
90% due to smoking

Question 2

Describe clinical syndromes of lung cancer

Answer 2

Central tumours, peripheral tumours, pancoast syndrome, paraneoplastic syndromes.
More peripheral now than central.

Question 3

Symptoms and signs of Central lung tumours

Answer 3

cough, hemoptysis, SOB, SVC Obstruction

Question 4

Symptoms and signs of peripheral lung tumours

Answer 4

usually asymptomatic, may present with chest wall pain or as a Pancoast tumor (apical - invade brachial plexus, etc.)
Pancoast syndrome – shoulder/arm pain, Horner’s syndrome, arm weakness/muscle atrophy

Question 5

Symptoms and signs of metastases from lung cancer

Answer 5

Nodal: neck mass
Bone: pain, pathological fracture, spinal cord compression
Liver: right upper quadrant pain, weight loss, fatigue anorexia
Brain: headache, neurological deficit, seizures, nausea
Other: can metastasize to any organ

Question 6

Signs and symptoms of paraneoplastic syndromes of lung cancer

Answer 6

other things caused by cancer
Endocrine: Hypercalcemia (PTH-RH), hyponatremia (SIADH), Cushing’s syndrome
Neurologic: Immune-mediated with autoantibodies
Hematologic: Anemia, leukocytosis, thrombocytosis
Dermatologic: Hypertrophic pulmonary osteoarthropathy (clubbing)

Question 7

Common metastases to lung

Answer 7

Breast, GI, Renal cell, Melanoma, Etc.

Question 8

Key lab tests and findings in lung cancer

Answer 8

MAJORITY require only histology Dx and CT of chest/upper abdomen to assess and come up with management
Biopsy: Non-small cell (usually Sx) versus small cell (almost never Sx)
Chest X-ray: central/peripheral, effusion, mediastinal nodes, other nodules, bone mets
CT Scan (chest/upper abd): mediastinal nodes, metastases
Bronchoscopy: tissue diagnosis and staging
Mediastinoscopy: tissue diagnosis and staging
Surgical procedure
Percutaneous transthoracic biopsy
Pulmonary function tests
Important to assess pulmonary reserve prior to treatment
Positron Emission Tomography (PET) Scan (more radioactive glucose take up by cancer

Question 9

Tx of lung cancer

Answer 9

NSCL I/II: Sx removal. Pneumonectomy vs lobectomy
III: chemo/radiation
IV: radiation, maybe chemo
SCL: chemo with radiation.

Question 10

Lung nodule vs a lung mass

Answer 10

Mass ≥ 3cm. More commonly malignant.

Nodule: 20-50% malignant

Question 11

What can a lung nodule be?

Answer 11

Cancer: metastases, primary lung cancer
Benign: granulomas, benign tumours, vascular malformation, lymph nodes

Question 12

Risks for lung cancer

Answer 12

Increasing age (>35 years)
Prior pulmonary disease (especially COPD)
History of tobacco exposure
Quantity smoked
Exposure to other carcinogens (asbestos)
History of cancer (either thoracic or extra-thoracic)

Question 13

CXR and CT findings on lung nodules

Answer 13

CXR and CT

• Size of the lesion: > 3 cm suggests cancer
• Doubling time: 2x increase in vol = 1.3x increase diameter - need repeat images. Benign is 2 yrs or shrink
• Margin characteristics: smooth, clear border = benign
• Calcification patterns: more in benign, unless erratic/eccentric

Question 14

Other Key investigations and findings for lung nodules

Answer 14

Bronchoscopy: useful for large airways, but not perfect
Transthoracic biopsy: good for Dx of malignancy, can cause bleeding/pneumothorax
PET scanning: higher uptake in malignancy
Sx biopsy: gold standard, whole chunk is removed anyways and can give info on staging, but more work/risks, etc.

Question 15

Tx and management

Answer 15

Wait and see if: Very low risk of malignancy, Poor surgical candidates, Refusal by patient to undergo invasive procedures, Benign lesion on non-surgical biopsy - follow up