Examining the Role of Bronchoscopy in Patients with Hematological Malignancies

Pulmonary infections have been shown to be the primary cause of infectious death in patients with hematological malignancies.[1] Rapid diagnosis and treatment are therefore crucial when patients present with pulmonary infiltrates, often associated with prolonged neutropenia. There are currently no specific guidelines for diagnosing and treating pulmonary infections in this subgroup of patients. However, bronchoscopy with brochoalveolar lavage (BAL) has been regarded as the first diagnostic tool when immunosuppressed patients develop pulmonary infiltrates with a reported diagnostic yield of 23-66%.[2]Nevertheless, it is important to note that many of these studies preceded the general use of aspergillus prophylaxis for leukemic patients, galactomannan antigen testing in serum, CMV PCR testing, routine PCP prophylaxis in patients with ALL and the availability of PCR testing for the detection of viral infection from nasopharyngeal swabs.

We have hypothesized that with more effective fungal prophylaxis and non-invasive testing the utility of bronchoscopy in immunosuppressed patients with pulmonary infiltrates is not as high as previously stated and may delay more definitive diagnosis such as with the use of video-assisted thoracoscopic surgery (VATS). As thrombocytopenia often precludes accessing tissue by bronchoscopic biopsy, VATS is also the only reliable procedure to diagnose inflammatory diseases such as organizing pneumonia and diffuse alveolar damage.

Methods:

We performed a retrospective review of hospitalized hematologic malignancy patients at our institution from April 2013 to April 2016 who underwent fiberoptic bronchoscopy with BAL with or without transbronchial biopsy for lung infiltrates found on imaging studies. The patients' medical records were reviewed for age, sex, underlying hematologic illness, WBC count, chest imaging findings, BAL and biopsy results, and treatment modification. Treatment modification was defined as the addition or change of therapy that was directly related to findings from either BAL or biopsy.

Results:

Forty patients with hematologic malignancies and lung infiltrates underwent bronchoscopy with or without biopsy between April 2013 and April 2016. Of these patients, 24 had AML, 8 had MM, 3 had ALL, 4 had DLBCL, and 1 had Marginal Zone Lymphoma. Of note, 13 patients had transbronchial biopsies in addition to BAL, and one of these patients experienced a pneumothorax from the biopsy. 22 of 40 patients (55%) were neutropenic at the time of the procedure. 24 of 40 BAL samples were negative by stain and culture. 11 of 40 showed Candida species considered to be a contaminant. Positive results included two patients with Pneumocystis, and one patient each with Mucormycosis, mixed bacteria (E. coli, Klebsiella, Enterobacter), and Streptococcus Viridans. One patient was also positive for Influenza A, however this patient was noted to be positive for this on a nasopharyngeal swab prior to the procedure. Of the 13 transbronchial biopsies performed, a single specimen (1/13) showed organizing pneumonia. Excluding Candida as a contaminant, the overall yield of BAL was 13% and the yield for biopsy was 8%. Only 4 patients had their treatments modified secondary to BAL or biopsy findings. These 4 modifications were the addition of steroids for organizing pneumonia, trimethoprim-sulfamethoxazole for Pneumocystis which occurred twice, and levofloxacin for the patient with mixed bacteria. Treatment modification secondary to BAL or biopsy results occurred in 10% of patients.

Discussion:

We conclude that in the current era of improved prophylaxis and non-invasive detection of respiratory pathogens and aspergillus, that the results from bronchoscopy rarely result in a substantive change in management and perhaps with the exception of BAL for patients with suspected diffuse alveolar hemorrhage, patients should proceed to VATS.

1. Choi, Moon. Acute Pulmonary Complications in Patients with Hematologic Malignancies.RadioGraphics 2014; 34: 1755-1768

2. Kim, Sei. Diagnostic value of bronchoscopy in patients with hematologic malignancy and pulmonary infiltrates. Ann Hematol 2015; 94: 153-159

3. Chellapandian D, Lehrnbecher T, Phillips B, et al. Bronchoalveolar lavage and lung biopsy in patients with cancer and hematopoietic stem-cell transplantation recipients: a systematic review and meta-analysis. J Clin Oncol 2015; 33: 501-9