Utility of flexible bronchoscopy in patients with hematologic malignancy seen in the chest unit of the National Cancer Institute.

Utilidad de la broncoscopia flexible en pacientes con neoplasia hematológica atendidos en la unidad de tórax del Instituto Nacional de Cancerología

Introduction. Pulmonary complications are common in patients with hematologic neoplasms, occurring in up to 60% of cases, which can be of infectious or non-infectious origin, increasing morbidity and mortality. (1) (2).  Previous studies have shown that bronchoalveolar lavage (BAL) and transbronchial or endobronchial biopsies can identify pathogens in a significant percentage of patients, facilitating adjustments to initial empirical treatment. (3) (4) . Despite advances in medical literature, there are still limitations in understanding the diagnostic utility of bronchoscopy in patients with hematologic neoplasms, especially in those already receiving empirical treatment. Additionally, there is a lack of consensus on the actual impact of bronchoscopy on treatment modification and its influence on clinical outcomes.

Materials and Methods. A retrospective cohort study was conducted in patients over 18 years of age with hematologic neoplasms, treated in the thoracic service of the National Cancer Institute between January 2017 and April 2022. A total of 162 patients with a confirmed diagnosis of hematologic neoplasm requiring flexible bronchoscopy with bronchoalveolar lavage (BAL) and/or transbronchial/endobronchial biopsy were included, excluding those with contraindications such as severe oxygenation disorders, hemodynamic instability, or severe thrombocytopenia. Patients in intensive care were excluded due to lack of information on bronchoscopy results.

Data were obtained from electronic medical records, and a validated collection instrument was used. Statistical analysis included measures of central tendency and dispersion for quantitative variables, and absolute and relative frequencies for qualitative variables. Diagnostic utility was defined as the proportion of patients whose treatment was modified following bronchoscopy.

Results. Microbiological isolation was identified in 28% of cases, with Mycobacterium tuberculosis being the most frequent pathogen (20%), followed by Pseudomonas aeruginosa and Klebsiella pneumoniae (13% each). Histopathological findings were documented in 5% of cases, with non-Hodgkin lymphoma being the most frequent pathology. Bronchoalveolar lavage (BAL) was performed in 56.2% of cases, BAL + transbronchial biopsy in 34%, and BAL + endobronchial biopsy in 7.4%. Findings impacted treatment in 16% of patients (n=26).

Conclusions: Bronchoscopy with BAL and/or transbronchial or endobronchial biopsy is a diagnostic tool whose utility varies depending on the type of disease, progression, and prior empirical treatment. In the current era of improved prophylaxis in these patients, bronchoscopy results may lead to only minimal changes in treatment.