Bleeding risk and diagnostic yield of bronchoscopy in hematologic malignancies: Platelet count as a predictor

Patients with hematologic malignancies frequently require diagnostic bronchoscopy for the evaluation of pulmonary complications, but thrombocytopenia complicates procedural safety and decision-making. We aimed to identify a platelet count threshold associated with increased intraprocedural bleeding risk during bronchoscopy with biopsy or brushing in this population.

We conducted a single-centre retrospective cohort study of adults with hematologic malignancies who underwent diagnostic bronchoscopy between 2010 and 2023. Bleeding was graded according to the Nashville Bleeding Scale (grade 1-4). Among procedures including transbronchial lung biopsy (TBLB) and/or endobronchial brushing, receiver operating characteristic (ROC) curve analysis was used to identify the platelet count cut-off associated with grade 2-4 bleeding.

Overall, 122 bronchoscopies were performed in 117 patients; 16 procedures (13.1%) were complicated by grade 2-4 bleeding. Among the 89 procedures involving TBLB and/or brushing, the optimal platelet count cut-off for predicting grade 2-4 bleeding was 8.2 × 10⁴/μL (area under the ROC curve 0.73, 95% CI 0.59-0.88; sensitivity 85.7%; specificity 65.7%). No procedure-related deaths occurred. TBLB yielded a pathological diagnosis in 22.4% (17/76) of procedures, while brushing cytology was diagnostic in 3.6% (2/55). Organizing pneumonia was the most frequent histopathological diagnosis, followed by lung cancer and fungal infection.

In patients with haematologic malignancies and thrombocytopenia, bronchoscopy with biopsy or brushing provides clinically useful diagnostic information but carries an increased bleeding risk at lower platelet counts. A platelet count of approximately 8.2 × 10⁴/μL may serve as a reference point indicating increased bleeding risk at lower counts during TBLB and brushing, rather than a definitive "safe" threshold. However, given the limited number of bleeding events, this should be regarded as an exploratory finding requiring validation in larger, prospective studies.