Surgical lung biopsy analyses differ by race and ethnicity in interstitial lung disease.

Aim: Establishing an interstitial lung disease (ILD) diagnosis may require surgical lung biopsy (SLB). While prior studies have described the epidemiology of ILDs among different races and ethnicities, the pathological and clinical diagnoses based on SLBs associated with these demographics are unexplored. Methods: We reviewed SLBs performed between 2000 and 2022 at the University of California San Francisco (UCSF) and the University of Chicago (UChicago) assessing histopathology using structured data collection forms. We analysed differences in histopathological features among White, Black, Asian, Hispanic and Native American participants. Results: A total of 1100 patients (899 UCSF and 201 UChicago study subjects, respectively) with chronic ILD underwent SLBs. 80.6% of patients were White, 6.7% Black, 5.7% Asian, 5% Hispanic and 1.9% Native American. The mean age was 61 years, with Black participants being younger (53 years). Notable histopathological differences include higher frequency of germinal centre formation in Black participants who also had less microscopic honeycombing, and less frequency of organising pneumonia in Hispanic participants. Hispanic participants had pathological nonspecific interstitial pneumonia (NSIP) whereas Native American participants mostly had fibrosing interstitial pneumonia. Hypersensitivity pneumonitis (HP) was the most common clinical diagnosis in White and Hispanic participants, connective tissue disease-ILD in Black participants and unclassifiable ILD in Native American participants. HP and NSIP frequently require SLB. Conclusions: This study demonstrates significant racial and ethnic differences in pathological and clinical diagnoses among ILDs. Recognising these differences is critical for tailoring diagnostic approaches and may impact precision medicine approaches for ILD management.