PURPOSE: The visualization of the parabronchial structures is very important especially in case of lymph node staging, diagnosis of intrapulmonary tumors and/or unknown hilar or mediastinal lympadenopathy and of mediastinal tumors. Today, real time endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA) is used very effectively for tissue confirmation in these occasions. Lymph node selection for TBNA is of bronchoscopist's decision. Endosonographic features of the lesions have long been discussed and published mostly for the breast lesions and gastrointestinal tumors but rarely for mediastinal lymph nodes.
METHODS: According to literature on peripheral lung lesions and other organ lesions, endosonographic features consistent with malignancy were reported as the round shape, absence of the blood vessel in the lymph node, hypoechogenicity, heterogeneity, irregular and hyperechoic margin, presence of hyperechoic dots, septations and anechoic cystic cavities. In this preliminary study, EBUS images of pathologic lymph nodes obtained in 32 consecutive patients (aged 39–89 mean 61, 12 malignant and 20 benign) were evaluated retrospectively by three readers blinded of the final diagnosis. Structural analysis of the pathologically proven lymph node image was based on the presence or absence of these nine features.
RESULTS: Initial statistical analysis showed that although absence of a blood vessel and presence of an irregular margin of the lymph node have a more powerful correlation with the malignancy, none of the features were found significantly correlated with the malignant pathology (r <0.50, p> 0.10).
CONCLUSION: We conclude that the characteristic EBUS features for benign and malignant lymph nodes need to be further analysed in a larger sample and our findings need to be further tested.
CLINICAL IMPLICATIONS: Endosonographic features consistent with malignancy have not been so far analysed together in a single study for mediastinal lymph nodes imaged under EBUS according to the published literature.
DISCLOSURE: Meltem Tor, Other Dr Tor is a bursary recipient from The Scientific and Technical Research Council of Turkey for her research visit to University of Pennsylvania Interventional Pulmonology Unit in 2007.; No Product/Research Disclosure Information