What are the signs of lung malignancy?

Signs of Lung Malignancy

Cough is the cardinal presenting symptom of lung cancer, occurring in 65% of patients at diagnosis, while approximately 25% remain asymptomatic with earlier-stage disease typically discovered incidentally. 1

Primary Pulmonary Manifestations

Respiratory Symptoms

• Chronic cough (65% of patients) results from endobronchial irritation, parenchymal infiltration, or postobstructive pneumonia—recurrent pneumonia in the same anatomic distribution or relapsing COPD exacerbations should raise immediate concern 1, 2
• Hemoptysis (25-33% of patients) warrants urgent evaluation for endobronchial tumor, particularly in smokers with COPD—even scant blood-streaking demands investigation as it may occur despite normal chest radiography 1, 3
• Dyspnea (17% at presentation) accompanies postobstructive pneumonia, pleural involvement, or pleural effusion 1, 4
• Chest pain (17.9% of patients) is initially nonspecific, but pleuritic quality strongly suggests pleural invasion 1, 4
• Localized or unilateral wheezing indicates endobronchial obstruction and mandates neoplasm evaluation 1

Physical Examination Findings

• Digital clubbing combined with pleural effusion or lobar collapse on examination is nearly pathognomonic for bronchogenic carcinoma in smokers 3
• Localized decreased breath sounds suggest lobar collapse or large mass effect 2

Signs of Intrathoracic Spread

Neurologic Involvement

• Hoarseness from recurrent laryngeal nerve palsy (more common with left-sided tumors due to the nerve's path under the aortic arch), causing vocal cord paresis and aspiration risk 1, 2
• Pancoast syndrome from superior sulcus tumors: shoulder/arm pain from brachial plexus invasion, Horner syndrome (ptosis, miosis, anhidrosis from sympathetic chain infiltration), and C8-T1-T2 distribution weakness with paresthesias 1
• Elevated hemidiaphragm from phrenic nerve dysfunction 1

Vascular and Structural Compression

• Superior vena cava syndrome (lung cancer is the leading cause): facial and neck swelling, dilated neck veins, prominent chest wall venous pattern, with possible dysphagia, cough, headache, or blurred vision 1
• Dysphagia from subcarinal adenopathy compressing the mid-esophagus 1
• Pleural effusion causing dyspnea or chest pain from direct tumor extension, metastatic implantation, or mediastinal lymphatic obstruction 1

Chest Wall Involvement

• Localized severe chest pain from pleural or chest wall invasion 2
• Painful soft tissue masses or rib destruction from chest wall invasion 2

Systemic and Metastatic Signs

Constitutional Symptoms

• Weight loss (8.3-33% of patients) with OR 2.1 for lung cancer diagnosis within 6 months 1, 4
• Fatigue (4.8% at presentation) with OR 1.6 for diagnosis within 6 months 1, 3
• Anorexia from chronic disease or paraneoplastic effects 5

Metastatic Disease Indicators

• Bone pain (5.9% initially, OR 2.7 at 6 months pre-diagnosis) suggesting skeletal metastases 1, 2
• Headaches potentially indicating brain metastases (present in 15% of small cell lung cancer at diagnosis) 1, 6
• Focal neurologic deficits from brain metastases 6
• Neck and supraclavicular lymphadenopathy (9.8% of patients, more common in nonsquamous carcinoma) 4

Paraneoplastic Manifestations

• Confusion, nausea, constipation, weakness from various paraneoplastic syndromes 2, 1
• Digital clubbing as a paraneoplastic sign significantly elevates diagnostic probability when combined with respiratory symptoms 3

Imaging Findings

• Central hilar lymphadenopathy (85% of small cell lung cancer cases) 6
• Mediastinal lymphadenopathy (75% of small cell lung cancer cases) 6

Critical Clinical Patterns

Symptomatic patients are more likely to have concurrent COPD and present with advanced disease (stage IIIB or IV), while asymptomatic patients typically have earlier-stage disease. 1, 2 Patients with squamous cell carcinoma are more likely to present with chronic cough and hemoptysis, while those with nonsquamous carcinoma more commonly present with metastatic pain and lymphadenopathy. 4 Stage IV disease correlates with higher rates of chest pain, dyspnea, weight loss, and fatigue compared to earlier stages. 4