[Chinese expert consensus on the clinical application of lung biopsy in interstitial lung disease].
Interstitial lung disease (ILD) comprises a highly heterogeneous group of pulmonary disorders, whose diagnosis often requires the integration of clinical, radiologic, and pathologic evidence. Lung biopsy is a key method for obtaining a histopathologic diagnosis, but unified standards are lacking for determining indications, selecting biopsy techniques, managing patients perioperatively, and integrating pathologic and clinical information. To address these gaps, the Respiratory Physicians Branch of the Chinese Medical Doctor Association and the ILD Group of the Chinese Thoracic Society spearheaded this initiative, collaborating with national experts in respiratory medicine, radiology, pathology, thoracic surgery, and rheumatology to formulate this consensus. Developed in strict adherence to evidence-based medicine principles, this consensus is founded on systematic literature reviews and evidence grading, utilizing the Delphi method for anonymous voting. It culminates in 15 recommendations, each explicitly annotated with the level of evidence and strength of recommendation. This consensus systematically delineates the multidisciplinary discussion (MDD)-centered full-process management of lung biopsy. The main contents encompass: assessment of the necessity and feasibility of lung biopsy; indication stratification strategies based on HRCT patterns; applicability scenarios and selection pathways for the four major lung biopsy techniques; shared decision-making; perioperative comprehensive management; management strategies for acute exacerbation of ILD (AE-ILD); standardization of tissue processing and pathological reporting; the post-biopsy MDD process for integrated diagnosis; and biopsy decision-making in special clinical contexts, such as ILD complicated by lung cancer or connective tissue disease-associated ILD (CTD-ILD). This consensus aims to provide clinicians with clear, safe, and practical guidance on lung biopsy, promote standardized and precise decision-making, and improve patient outcomes.Summary of RecommendationsRecommendation 1: For patients with suspected ILD, a comprehensive multidisciplinary discussion (MDD) is mandatory prior to lung biopsy. This evaluation should establish the diagnostic certainty of the preliminary clinical assessment, evaluate the clinical utility of the biopsy, and facilitate shared decision-making (SDM) that incorporates patient preferences (Level of evidence: 3, Recommendation: strong).Recommendation 2: For ILD patients in whom the diagnosis remains uncertain following a comprehensive non-invasive evaluation, or when precise histopathologic subtyping is required, a lung biopsy is recommended to establish a definitive diagnosis and guide the therapeutic management (Level of evidence: 4, Recommendation: strong).Recommendation 3: For patients with an interstitial pattern, a lung biopsy is strongly discouraged if HRCT demonstrates a definite UIP pattern and secondary etiologies have been excluded. A conditional recommendation for a lung biopsy applies to patients with a probable UIP patterns in whom NSIP or fibrotic HP cannot be ruled out. A lung biopsy is strongly recommended to achieve a definitive diagnosis in patients with an indeterminate or non-UIP patterns and insufficient clinical evidence (Level of evidence: 4, Recommendation: conditional).Recommendation 4: For patients with an alveolar filling pattern, a lung biopsy is recommended to clarify the etiology once infection, alveolar hemorrhage, and pulmonary edema have been systematically excluded, and there is either a lack of response to empirical therapy or a clinical necessity to differentiate the lesion from malignancy (Level of evidence: 2, Recommendation: strong).Recommendation 5: For suspected rare ILDs, including PAP, iEP, LAM, and LIP, non-invasive or minimally invasive diagnostic modalities should be prioritized; a lung biopsy is conditionally recommended if these approaches are non-diagnositic. Conversely, a lung biopsy is strongly recommended for patients with clinically suspected AFOP or PLCH (Level of evidence: 2, Recommendation: conditional).Recommendation 6: Lung biopsy is not recommended for patients with acute respiratory failure, severe pulmonary functional impairment, recent cardiovascular events, hemodynamic instability, significant pulmonary hypertension, severe coagulopathy, or end-stage systemic debilitation (Level of evidence: 1, Recommendation: strong).Recommendation 7: Site selection for lung biopsy should target active lesions identified on HRCT (e.g., ground-glass opacities or fine reticulation). Specimens must include the interface between diseased and normal parenchyma to facilitate pattern assessment. High-risk areas, such as major vessels and severe bullae, must be strictly avoided. Multi-lobar sampling from at least two sites of varying severity is recommended to adequately capture disease heterogeneity (Level of evidence: 4, Recommendation: strong).Recommendation 8: A TBLB is recommended as the first-line diagnostic approach for suspected granulomatous diseases (e.g., sarcoidosis) and specific alveolar filling patterns. If a TBLB is non-diagnostic, escalation to TBLC or SLB is advised. A TBLB is not recommended for the evaluation of predominantly fibrotic ILDs (e.g., UIP or NSIP) (Level of evidence: 4, Recommendation: strong).Recommendation 9: TBLC is recommended as the preferred modality in expert centers, particularly for patients who are poor candidates for or are averse to SLB. The procedure should be standardized under general anesthesia with prophylactic balloon placement for hemorrhage control and integrated with imaging or navigational guidance to optimize diagnostic yield while minimizing procedural complications (Level of evidence: 2, Recommendation: strong).Recommendation 10: SLB is recommended for patients in whom TBLC yields a non-diagnostic result, provided their cardiopulmonary physiological reserve permits surgical intervention. Video-assisted thoracoscopic surgery (VATS) is the preferred approach, requiring sampling from at least two distinct lobes. Biopsies should prioritize the dependent segments of the upper lobes or the superior segments of the lower lobes; sampling from the lingula or the right middle lobe should only be considered if these sites harbor the most representative lesions and no superior alternatives exist (Level of evidence: 2, Recommendation: strong).Recommendation 11: PTNB is recommended for the diagnosis and differential diagnosis in ILD patients presenting with solitary nodules, masses, or focal consolidations, particularly to rule out malignancy. However, it is not recommended for the histopathological evaluation of diffuse fibrosing ILDs (Level of evidence: 2, Recommendation: strong).Recommendation 12: A shared decision-making model is recommended throughout the biopsy selection process. Clinicians should thoroughly counsel patients regarding the benefits, risks, and alternatives of the procedure, ultimately formulating a clinical plan that aligns medical evidence with patient values (Level of evidence: 4, Recommendation: strong).Recommendation 13: Histological or imaging patterns of usual interstitial pneumonia (UIP), active disease phase, and reduced diffusing capacity for carbon monoxide (DLCO) are the main risk factors for acute exacerbation of interstitial lung disease (AE-ILD). Routine prophylactic use of glucocorticoids or antifibrotic therapy is not recommended for all patients; instead, meticulous perioperative management is recommended to prevent acute exacerbations. Once AE occurs, the underlying cause should be promptly investigated, and high-dose glucocorticoids along with supportive therapy may be considered (Level of evidence: 2, Recommendation: strong).Recommendation 14: Histopathological reports must adhere to current international standardized nomenclature, prioritizing the description of the predominant histological patterns and their salient features, while specifically noting any findings indicative of a specific etiology. Diagnostic limitations secondary to suboptimal specimen quality must be explicitly stated. Pathologists are required to provide a systematic and standardized microscopic description of the tissue pathology, formulate a histopathological classification, and offer etiological insights whenever feasible (Level of evidence: 4, Recommendation: strong).Recommendation 15: Post-biopsy MDD is central to formulating an integrated diagnosis and should be conducted by the same cohort of clinicians, radiologists, and pathologists involved in the initial evaluation. A systematic correlation between the histopathology and the clinical andradiologic data is required; any discordances must be thoroughly analyzed to achieve a consensus integrated diagnosis and guide therapeutic planning. If an integrated diagnosis cannot be established, a subsequent MDD or referral to an expert center for a repeat biopsy is warranted (Level of evidence: 2, Recommendation: strong).