What are the symptoms of lung cancer?

Symptoms of Lung Cancer

Lung cancer presents with a spectrum of symptoms ranging from primary pulmonary manifestations to signs of intrathoracic spread and distant metastases, with approximately 75% of patients symptomatic at diagnosis—though notably, 25% remain asymptomatic and are more likely to have earlier-stage disease. 1, 2

Primary Pulmonary Symptoms

The cardinal respiratory symptoms include:

• Cough is the most common presenting symptom, occurring in 25-84% of patients (most commonly cited as 65%), resulting from endobronchial irritation, parenchymal infiltration, or postobstructive pneumonia 1, 2, 3

  • Recurrent pneumonia in the same anatomic distribution or relapsing COPD exacerbations should raise concern for underlying neoplasm 1
  • Productive cough occurs in approximately 25% of patients 1

• Hemoptysis presents in 25-33% of patients and warrants immediate concern for endobronchial tumor, particularly in smokers with COPD 1, 2, 4

  • Even scant blood-streaking in sputum should raise suspicion, as it may occur despite normal or nonlocalizing chest radiography 1, 2
  • Persistent hemoptysis, even in small amounts, demands evaluation for endobronchial tumor 1

• Dyspnea affects approximately 17% at presentation and may accompany postobstructive pneumonia, pleural involvement, or airway obstruction 1, 2, 5

• Chest pain occurs in 17.9% of patients and is often nonspecific initially, but pleuritic pain suggests pleural invasion or chest wall extension 1, 2, 5

• Localized or unilateral wheezing reflects endobronchial obstruction and should prompt immediate evaluation for neoplasm 1, 2

Symptoms of Intrathoracic Spread

When tumor extends beyond the primary site, specific syndromes emerge:

• Hoarseness from recurrent laryngeal nerve palsy (more common with left-sided tumors due to the nerve's circuitous route under the aortic arch), causing vocal cord paresis and predisposing to aspiration 2

• Pancoast syndrome from superior sulcus tumors includes shoulder/arm pain from brachial plexus invasion, Horner syndrome (ptosis, miosis, anhidrosis from sympathetic chain infiltration), and C8-T1-T2 distribution weakness and paresthesias 2

• Superior vena cava syndrome (lung cancer is the most common cause) presents with facial and neck swelling, dilated neck veins, prominent chest wall venous pattern, and occasionally dysphagia, cough, headache, or blurred vision 2

• Dysphagia from subcarinal adenopathy compressing the mid-esophagus 1, 2

• Phrenic nerve dysfunction manifesting as elevated hemidiaphragm 2

• Pleural effusion causing dyspnea or chest pain, from direct tumor extension, metastatic implantation, or mediastinal lymphatic obstruction 1, 2

Systemic and Metastatic Manifestations

Constitutional symptoms indicate more advanced disease:

• Weight loss occurs in 8.3-33% of patients with an odds ratio of 2.1 for lung cancer diagnosis within 6 months 2, 4, 5

• Fatigue presents in 4.8% initially with an odds ratio of 1.6 for diagnosis within 6 months 2, 4, 5

• Bone pain occurs in 5.9% initially (odds ratio 2.7 at 6 months pre-diagnosis), suggesting skeletal metastases 2, 5

• Headaches potentially indicate brain metastases 2

• Anemia from chronic disease or bone marrow involvement 2

• Neck and supraclavicular lymphadenopathy occurs in 9.8% of patients 5

• Digital clubbing in a smoker with pleural effusion or lobar collapse on examination is almost pathognomonic for bronchogenic carcinoma 4

Critical Clinical Patterns

Symptomatic patients are significantly more likely to have advanced disease (stage IIIB or IV) and concurrent COPD, while asymptomatic patients typically present with earlier-stage disease. 1, 2

• In stage I disease, 59% of patients have no symptoms, though 40% present with at least one symptom 6
• In stage IV disease, 27.7% still have no symptoms at diagnosis, emphasizing that absence of symptoms does not rule out advanced lung cancer 6
• Patients with squamous cell carcinoma are more likely to present with cough and hemoptysis compared to other histologic types 5
• The odds of having both symptoms and physical signs increase with more advanced stage at diagnosis 5