PURPOSE: We describe the diagnostic performance of EBUS-TBNA in a heterogeneous population of patients with mediastinal and hilar lymphadenopathy in a geographical region with a high prevalence of histoplasmosis related granulomatous inflammation.
METHODS: A review was performed of all patients referred for EBUS-TBNA over a 7 month period at two institutions. Cytological analysis of EBUS-TBNA aspirates were compared to a reference standard of definitive pathological tissue diagnosis or a composite of ≥6 month's clinical follow-up with radiographic imaging. Pre-EBUS CT chest studies were screened for evidence of calcified granulomatous inflammation. Definitive lymph node sampling was defined by lymphoid tissue, granulomatous inflammation or tumor. The results were classified as malignant, benign disease, normal or inadequate sample. The frequency of definitive lymph node sampling in those patients with and without calcified granulomatous mediastinal/hilar nodal inflammation was compared using a chi squared test with significant p value <.05. Institutional review board approval was attained.
RESULTS: All 38 patients (20 female, mean age 59) undergoing EBUS-TBNA were included. In total, 66 lymph nodes (mean size=12.8mm) and 4 masses were biopsied. Definitive lymph node sampling was achieved in 29/38 (76%) (excluding n=3 necrosis). The sensitivity, specificity, positive and negative predictive value and diagnostic accuracy of EBUS-TBNA for malignancy was 79%, 100%, 100%, 85% and 90% respectively. On pre-EBUS CT chest, 23 (61%) had calcified granulomatous inflammation (13 (34%) mediastinal/hilar lymph node involvement). The prevalence of cancer was similar in those with and without calcified granulomatous inflammation (35% and 40%). There was a trend towards a reduction in frequency of definitive lymph node sampling in those patients with (8/13) and without (21/25) mediastinal/hilar nodal calcified granulomatous inflammation, however this was not statistically different (p=0.12).
CONCLUSION: The presence of calcified granulomatous inflammation in a region with endemic histoplasmosis infection did not statistically influence the frequency of definitive lymph node sampling by EBUS-TBNA.
CLINICAL IMPLICATIONS: Calcified granulomatous inflammation consistent with histoplasmosis infection is not a contraindication to EBUS-TBNA.
DISCLOSURE: Yousef Shweihat, No Financial Disclosure Information; No Product/Research Disclosure Information