Using endobronchial ultrasound features to predict lymph node metastasis in patients with lung cancer.

PURPOSES: Reliable staging of the mediastinum determines TNM classification and directs therapy for non-small cell lung cancer (NSCLC). Our aim was to evaluate predictors of mediastinal lymph node metastasis in patients undergoing endobronchial ultrasound (EBUS). METHODS: Patients with known or suspected lung cancer undergoing EBUS for staging were included. Lymph node radiographic characteristics on chest CT/PET scan and ultrasound characteristics of size, shape, border, echogenicity, and number were correlated with rapid on-site evaluation (ROSE) and final pathology. Logistic regression (estimated with generalized estimating equations to account for correlation across nodes within patients) was used with cancer (vs normal pathology) as the outcome. ORs compare risks across groups, and testing was performed with two-sided α of 0.05. RESULTS: Two hundred twenty-seven distinct lymph nodes (22.5% positive for malignancy) were evaluated in 100 patients. Lymph node size, by CT scan and EBUS measurements, and round and oval shape were predictive of mediastinal metastasis. Increasing size of lymph nodes on EBUS was associated with increasing malignancy risk (P = .0002). When adjusted for CT scan size, hypermetabolic lymph nodes on PET scan did not predict malignancy. Echogenicity and border contour on EBUS and site of biopsy were not significantly associated with cancer. In 94.8% of lymph nodes with a clear diagnosis, the ROSE of the first pass correlated with subsequent passes. CONCLUSIONS: Lymph node size on CT scan and EBUS and round or oval shape by EBUS are predictors of malignancy, but no single characteristic can exclude a visualized lymph node from biopsy. Further, increasing the number of samples taken is unlikely to significantly improve sensitivity.

Bronchoscopy for the diagnosis and staging of lung cancer.

Bronchoscopy is an invaluable tool utilized for the diagnosis, staging, and management of lung cancer. Advancements in computer technology and engineering have allowed for the emergence of newer modalities to evaluate endobronchial, parenchymal, and mediastinal pathology. Established techniques such as white light video bronchoscopy and its ancillary procedures (forceps biopsy, brush biopsy, bronchoalveolar lavage, bronchial washings, and transbronchial needle aspiration) are discussed here, with their accuracy described in relation to tumor location, size, and type. Newer technologies such as autofluorescence bronchoscopy, narrow band imaging, endoscopic ultrasound, endobronchial ultrasound, electromagnetic navigation, optical coherence tomography, and confocal fluorescent laser microscopy are introduced and put into perspective. Special emphasis has been placed on their role in the early detection and staging of lung cancer. Some technology requires further study to delineate its role in the disease, whereas other modalities are emerging as the new gold standard in evaluation of lung cancer. The future holds great promise with further miniaturization of equipment and improvements in computer processing power that may allow for in vivo pathological evaluation of abnormal tissue.

Real-time endobronchial ultrasound-guided transbronchial lymph node aspiration.

BACKGROUND: Accurate staging of lung cancer requires noninvasive and pathologic examination of intrathoracic lymphadenopathy, which determines both the treatment options and prognosis. The gold standard for mediastinal staging has been mediastinoscopy. Other options include video-assisted thoracoscopic surgery, blind transbronchial needle aspiration, and endoscopic ultrasound-guided fine-needle aspiration. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has recently been introduced. Here we report the use of EBUS-TBNA as a diagnostic modality for mediastinal adenopathy and staging modality for lung cancer. METHODS: This was a retrospective analysis of 152 consecutive patients who underwent EBUS-TBNA with undiagnosed intrathoracic adenopathy or cancer staging as the primary indications. The procedures occurred between January 2005 and June 2006 at a single academic medical center. Of the 152 patients, 117 were included in the final statistical analysis after excluding those with benign disease diagnosed by EBUS-TBNA. Rapid on-site cytopathologic examination was used in all cases. RESULTS: Malignancy was identified in 113 patients, of which 67 (59.3%) had non-small cell lung carcinoma, and 20 (17.7%) underwent surgical resection. Four patients had benign diagnoses at surgical pathology. Only 1 surgical patient was found to have nodal metastasis at a lymph node station previously biopsied by EBUS-TBNA (negative predictive value, 97%). Compared with radiologic staging, EBUS-TBNA down-staged 18 of 113 (15.9%) and up-staged 11 (9.7%). Sensitivity was 98.7%, with 100% specificity. No major complications were associated with the procedure. CONCLUSIONS: EBUS-TBNA is useful in accessing mediastinal and hilar lymph nodes for the diagnosis and staging of non-small cell lung cancer and other disorders of the mediastinum. Thoracic surgeons and pulmonologists are well positioned to use this tool in everyday practice.