Lung Cancer

Physical Examination

• General examination:

  • Cachexia or weight loss (common in lung cancer)

  • Signs of respiratory distress (e.g., use of accessory muscles, tachypnea)

  • Cyanosis (indicating hypoxia)

  • Horner's syndrome (ptosis, miosis, enophthalmos and anhidrosis) if the tumour is located at the lung apex (Pancoast tumour)

  • Clubbing of fingers or toes (suggesting chronic hypoxia)

  • Tar-stained in fingers

  • Peripheral lymphadenopathy (e.g., axillary or inguinal lymph nodes)

• Chest inspection:

  • Asymmetrical chest expansion (may indicate pleural effusion, lung collapse, or tumour)

  • Visible masses or deformities

  • Signs of pleural effusion (e.g., bulging intercostal spaces, reduced chest movement)

  • Superficial lymphadenopathy (e.g., supraclavicular lymph nodes)

• Palpation:

  • Chest wall tenderness or masses

  • Tracheal deviation (toward the lesion if lung collapse, away if large pleural effusion or tension pneumothorax)

  • Unequal tactile fremitus (reduced on the affected side)

  • Chest wall crepitus (suggesting pneumothorax or rib involvement)

• Percussion:

  • Dullness over the tumor, pleural effusion, or consolidated lung

  • Hyperresonance if pneumothorax is present

  • Stony dullness over an area of pleural thickening or pleural effusion

• Auscultation:

  • Decreased or absent breath sounds over the tumour or pleural effusion

  • Crackles (suggesting consolidation, fibrosis, or infection)

  • Wheezes (indicating airway obstruction)

  • Pleural rub (suggesting pleural inflammation)

• Additional examination (if required):

  • Low oxygen saturation (less than 95% on room air)

  • Signs of distant metastases (e.g., hepatomegaly, bone tenderness)

Investigations

• Laboratory tests:

  • Complete blood count (anaemia, thrombocytosis, leukocytosis)

  • Blood chemistry panel (renal and liver function, electrolytes)

  • Lactate dehydrogenase (LDH) (elevated in metastatic disease)

  • Serum calcium (hypercalcemia related to paraneoplastic syndrome)

  • Tumour markers (e.g., carcinoembryonic antigen, CEA)

• Imaging studies:

  • Chest X-ray (identify lung masses, pleural effusion, or lymphadenopathy)

  • Computed tomography (CT) scan of the chest (detailed imaging of lung parenchyma, mediastinum, and pleura)

  • Positron emission tomography (PET) scan (assess metabolic activity and possible metastasis)

  • Magnetic resonance imaging (MRI) (if needed for better assessment of chest wall, spine, or brain involvement)

  • Bone scan (detect possible bone metastases)

• Invasive tests:

  • Bronchoscopy (direct visualisation of airways, biopsy of suspicious lesions)

  • Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) (sampling mediastinal and hilar lymph nodes)

  • Percutaneous needle biopsy (transthoracic approach for peripheral lesions)

  • Thoracentesis (for pleural effusion evaluation and cytology)

  • Video-assisted thoracoscopic surgery (VATS) (biopsy and staging of lung cancer)

• Other tests:

  • Pulmonary function tests (PFTs) (assess baseline lung function and post-treatment predictions)

  • Electrocardiogram (ECG) (evaluate heart function and rule out cardiac-related symptoms)

  • Echocardiography (assess cardiac function, particularly in patients with symptoms suggestive of pericardial involvement)

  • Brain MRI or CT (evaluate for brain metastases if neurological symptoms present)

  • Genetic and molecular testing (identify targetable mutations or alterations, e.g., EGFR, ALK, ROS1)

Management

• General management:

  • Smoking cessation: reduce the risk of further lung damage and improve the overall health

  • Pulmonary rehabilitation: optimise lung function and exercise capacity

  • Nutritional support: maintain or improve weight and overall health

  • Psychosocial support: address anxiety, depression, and emotional challenges

• Medical management:

  • Chemotherapy: systemic therapy for non-resectable or metastatic disease

  • Targeted therapy: specific agents targeting molecular alterations (e.g., EGFR, ALK, ROS1)

  • Immunotherapy: immune checkpoint inhibitors to enhance the immune response against cancer cells

  • Palliative care: pain and symptom management, improving quality of life

• Surgical management:

  • Lobectomy: removal of affected lung lobe, the gold standard for early-stage non-small cell lung cancer (NSCLC)

  • Pneumonectomy: removal of entire lung, if tumour involves multiple lobes or central structures

  • Segmentectomy or wedge resection: removal of a lung segment or small part for patients with limited lung function or early-stage peripheral tumours

  • Lymph node dissection: removal and evaluation of lymph nodes for staging and prognosis

  • Video-assisted thoracoscopic surgery (VATS): minimally invasive surgery for early-stage tumours

• Other management:

  • Radiation therapy: definitive or adjuvant treatment for locally advanced NSCLC or palliative treatment for symptoms

  • Stereotactic body radiotherapy (SBRT): high-dose, precise radiation for early-stage NSCLC, especially in patients not suitable for surgery

  • Endobronchial therapies: laser ablation, stenting, or brachytherapy for airway obstruction management

  • Pleurodesis: management of recurrent malignant pleural effusions

  • Supportive care: oxygen therapy, bronchodilators, and antibiotics for infection management.

Causes of Lung Cancer

• Smoking: most significant risk factor, including cigarettes, cigars, and pipes; passive smoking also increases risk

• Environmental exposure:

• Asbestos: occupational exposure in construction, insulation, and shipbuilding industries; increased risk when combined with smoking

• Secondhand smoke: non-smokers exposed to tobacco smoke from smokers

• Occupational exposure:

• Asbestos: construction, insulation, shipbuilding industries; can cause asbestosis and increases lung cancer risk, especially when combined with smoking

• Medical history:

  • Family history: genetic predisposition or shared environmental risk factors

  • Prior radiotherapy: chest radiation for other cancers, such as breast or lymphoma

• Other factors:

  • Age: risk increases with age, most common in those over 65

  • Lifestyle: physical inactivity and excessive alcohol consumption may increase risk

Types of Lung Cancer

Lung cancer can be broadly categorized into two main types, which have distinct histological features, growth patterns, and treatment approaches:

1. Non-small cell lung cancer (NSCLC):

• Most common type, accounting for approximately 85% of lung cancer cases

• Subtypes:

  • Adenocarcinoma: originates in glandular cells, often found in peripheral lung tissue, and more common in non-smokers

  • Squamous cell carcinoma: arises from squamous cells lining the bronchi, typically found in central lung areas near bronchi

  • Large cell carcinoma: poorly differentiated tumor, can occur in any part of the lung, tends to grow and spread rapidly

• Generally slower-growing and more amenable to surgical intervention in early stages

1. Small cell lung cancer (SCLC):

• Less common, accounting for about 15% of lung cancer cases

• Strongly associated with smoking

• More aggressive, rapid growth, and early metastasis

• Typically managed with chemotherapy and radiation therapy rather than surgery