A lung biopsy serves as the definitive diagnostic tool when diagnostic imaging, such as computed tomography (CT) or positron emission tomography (PET), identifies abnormal tissue within the lung parenchyma, airways, or pleura. The core objective of the procedure is to extract adequate tissue for histopathology (microscopic cell examination), microbiological culture, and molecular profiling, including biomarker testing for targeted cancer therapies.

Pulmonary biopsies fall into three primary clinical categories: percutaneous transthoracic needle biopsy (guided by CT or ultrasound), flexible or rigid bronchoscopic biopsy (including endobronchial ultrasound and navigational bronchoscopy), and surgical lung biopsy (utilizing video-assisted thoracoscopic surgery or open thoracotomy). Method selection depends on lesion location, patient pulmonary function, and necessary tissue volume.

Lung biopsy procedures are performed using image-guided, endoscopic, or surgical approaches based on lesion characteristics. For CT-guided percutaneous needle biopsy, the patient is positioned on a scan table, and local anesthesia is infiltrated into the skin and chest wall tissue down to the pleura. Guided by real-time CT acquisition, an interventional radiologist advances a coaxial needle through the chest wall into the target pulmonary lesion. Core biopsy samples are obtained using an automated spring-loaded cutting needle, often accompanied by fine-needle aspiration (FNA) for cytological review. For bronchoscopic approaches, a flexible endoscope or robotic catheter is advanced through the mouth or nose into the tracheobronchial tree under conscious sedation or general anesthesia. Using fluoroscopy, radial endobronchial ultrasound (r-EBUS), or electromagnetic navigation, the pulmonologist guides biopsy forceps or needles to sample parenchymal or mediastinal lesions. Surgical biopsies involve direct thoracic access under general anesthesia to resect wedge samples of lung tissue.

Undergoing a lung biopsy offers essential diagnostic advantages when evaluating abnormal lung tissue:

• Definitive Histological Diagnosis: Establishes tissue diagnosis, eliminating ambiguity associated with radiological imaging alone (American College of Chest Physicians [ACCP] Guidelines 2013).
• Enables Molecular Profiling: Yields adequate tissue for genomic biomarker testing, essential for selecting targeted biological agents and immunotherapy in non-small cell lung cancer (National Comprehensive Cancer Network [NCCN] Guidelines 2024).
• Prevents Diagnostic Delay: Facilitates timely identification of active infectious or rapidly progressive malignant diseases, allowing prompt therapeutic intervention.
• Guides Non-Cancer Management: Provides histological subtyping of complex interstitial lung diseases, steering appropriate corticosteroid or immunosuppressive management (ATS/ERS/JRS/ALAT Clinical Practice Guideline 2022).
• High Diagnostic Yield: Modern image-guided percutaneous and robotic-assisted endoscopic procedures demonstrate diagnostic accuracy rates exceeding 85% to 90% for accessible lesions.

Recovery timelines vary according to the biopsy procedure performed. Following percutaneous CT-guided needle biopsy or flexible bronchoscopy, patients remain in a recovery area for two to four hours while vital signs and breath sounds are regularly evaluated. A routine post-procedure chest radiograph is performed to verify absence of pneumothorax. Minor hemoptysis (blood-streaked sputum) and mild local chest wall discomfort are common during the initial 24 to 48 hours.

Patients undergoing outpatient needle or bronchoscopic biopsies may resume light sedentary daily activities within 24 to 48 hours, while strenuous physical exercise, heavy lifting (>10-15 lbs), and commercial air travel must be avoided for one to two weeks to reduce pneumothorax risks. Recovery following surgical lung biopsy (VATS or open thoracotomy) requires an inpatient hospital stay of one to four days with chest tube management, with full functional recovery typically achieved over two to six weeks.

Lung biopsy procedures are indicated for diagnosing and evaluating a broad spectrum of pulmonary conditions, including:

• Pulmonary Nodules and Masses: Evaluation of indeterminate pulmonary nodules, solitary pulmonary nodules (SPNs), or expanding lung masses detected on chest radiographs or CT scans.
• Primary and Metastatic Malignancies: Histological identification and staging of non-small cell lung carcinoma (NSCLC), small cell lung carcinoma (SCLC), primary pulmonary lymphomas, and secondary metastatic tumors originating from other organs.
• Diffuse Parenchymal Lung Diseases (DPLD): Subtyping of interstitial lung diseases, including idiopathic pulmonary fibrosis (IPF), sarcoidosis, hypersensitivity pneumonitis, and connective tissue disease-associated ILD.
• Unexplained Pulmonary Infections: Identification of atypical infectious pathogens, including fungal infections (e.g., aspergillosis, histoplasmosis), mycobacterial diseases (e.g., tuberculosis), and opportunistic infections in immunocompromised individuals.
• Benign Pulmonary Lesions: Diagnosis of benign entities such as pulmonary hamartomas, vascular malformations, inflammatory pseudotumors, and granulomas.

Pre-procedure preparation requires a thorough clinical assessment, including a complete blood count, coagulation profile (PT/INR, aPTT), and baseline renal panel. Patients must disclose all prescription antiplatelet medications (such as aspirin, clopidogrel, or ticagrelor) and anticoagulants (such as warfarin, rivaroxaban, or apixaban), which are typically discontinued three to seven days prior to the procedure under physician guidance to mitigate bleeding risks. Fasting (nil per os) is required for six to eight hours prior to biopsy procedures involving sedation or anesthesia. Pre-procedure pulmonary function tests (PFTs) may be performed to evaluate baseline ventilatory reserve, particularly in patients with underlying chronic obstructive pulmonary disease or pulmonary fibrosis.

Complications associated with lung biopsy depend on procedure type, lesion location, and underlying lung function. The primary risk of percutaneous transthoracic needle biopsy is pneumothorax, occurring in approximately 15% to 25% of cases, with roughly 2% to 6% requiring intercostal chest tube placement for lung re-expansion. Pulmonary parenchymal hemorrhage and minor hemoptysis occur in 5% to 10% of percutaneous biopsies, typically self-limiting. Rare but severe risks include tension pneumothorax, major airway or vascular laceration, systemic air embolism (<0.1%), hemothorax, procedural infection, and anesthesia-related complications. Transbronchial biopsies carry a lower risk of pneumothorax (1% to 3%) but higher potential for localized airway bleeding.

The patient journey for a lung biopsy begins with a comprehensive pre-procedure evaluation, including thoracic imaging review, pulmonary function testing, and temporary cessation of blood-thinning medications. On the day of the procedure, local anesthesia, conscious sedation, or general anesthesia is administered based on the chosen biopsy technique. During the procedure, image guidance or endoscopic visualization ensures targeted sampling of the suspected lesion while minimizing trauma to surrounding lung tissue.

Following tissue collection, patients undergo immediate post-procedure monitoring and a chest X-ray to rule out a pneumothorax (air leakage into the pleural space causing partial or total lung collapse). Most outpatient biopsies allow discharge within two to six hours if post-procedure imaging is clear. Complete pathology results, including molecular biomarker analysis when indicated, are typically finalized within three to seven business days, guiding subsequent treatment strategies.