How is it Diagnosed?
Lung cancer diagnosis involves a combination of imaging, histopathological evaluation,
and molecular testing. The process often starts with symptoms like persistent cough,
hemoptysis, chest pain, unexplained weight loss, or dyspnea, especially in smokers or
individuals with significant exposure to carcinogens.
Chest X-ray is typically the first investigation and may reveal a mass, nodule, or pleural
effusion. However, contrast-enhanced CT scan of the thorax is more sensitive and
provides detailed information about tumor size, location, lymph node involvement, and
metastasis. PET-CT scans are used to assess the metabolic activity of lesions and
detect distant spread.
Sputum cytology can detect malignant cells in centrally located tumors. Bronchoscopy
is used for visual assessment and biopsy of endobronchial lesions. For peripheral
lesions, CT-guided transthoracic needle aspiration/biopsy is performed.
Once malignancy is confirmed, further testing including MRI brain, bone scans, and
abdominal imaging may be done for staging. Molecular testing (e.g., EGFR, ALK, PD-L1
mutations) is crucial for non-small cell lung cancer to guide targeted therapy.
Histological classification (non-small cell vs. small cell) is vital for treatment planning.
Multidisciplinary evaluation ensures precise staging (TNM classification) and
management, combining surgery, chemotherapy, radiation, or targeted therapy.