Value of computed tomography and mediastinoscopy in preoperative evaluation of mediastinal nodes in non-small cell lung cancer A study of 569 patients

Abstract

The efficacy of computed tomography (CT) and mediastinoscopy as staging modalities to assess mediastinal lymph node status was evaluated in 569 patients with a presumed resectable non-small cell lung cancer (NSCLC). Computed tomography scan was performed in every patient and followed by mediastinoscopy in 331 and by thoracotomy in 477 patients. Mediastinal lymph nodes on CT larger than 1.5 cm were considered pathological. Overall, CT had a sensitivity of 69%, a specificity of 71% and an accuracy of 71% in identifying mediastinal lymph node metastases. For mediastinoscopy these figures were 72%, 100% and 89%, respectively. Computed tomography accuracy was distinctly lower in squamous cell carcinomas and in central tumors, as CT sensitivity was significantly lower in left-sided tumors. The positive predictive value (PPV) of CT in T1 lesions (29%) and PPV and negative predictive value (NPV) of CT in T2 squamous cell carcinomas (30% and 83%, respectively) were low, so questioning its use in those instances. We perform a mediastinoscopy in every situation except for squamous cell carcinomas or small (less than 3 cm) peripheral tumors in the absence of enlarged mediastinal lymph nodes. This selective attitude is rewarding since a) the number of pN2 in the straight thoracotomy group was only 16% versus 41% in the mediastinoscopy group, b) the exploratory thoracotomy rate in the straight thoracotomy group was low (4.6%).

The role of positron emission tomography with18F-fluoro-2-deoxy-D-glucose in respiratory oncology

“…In prospective data from the Radiological Diagnostic Oncology Group, the sensitivity and speci®city of thoracic CT were only 52% and 69%, respectively [68]. In the authors9 (the University Hospital Gasthuisberg), the best results were obtained when LNs ¢1.5 cm at their maximal cross-sectional diameter were considered to be metastatic [69]. Using this criterion, the sensitivity was 69% and the speci®city 71%.…”

Integrated PET/CT in the staging of nonsmall cell lung cancer: technical aspects and clinical integration

“…The current consensus considers a node .10 mm in short axis diameter as suspect for metastatic lymph node [33]. Different studies with CT have shown a marked heterogeneity in the results, going from 69% to 82% for specificity and from 52% to 69% for sensitivity [41].…”

Mediastinoscopy in Assessing Mediastinal Lymphadenopathy and Lung Disease

“…A mediastinum that appears normal upon CT may harbor metastatic disease in 13% of cases. It is well known that a positive CT result predicts actual metastatic involvement in half of the patients, and these patients require mediastinoscopy to confirm or rule out micrometastasis [8]. Mediastinoscopy has proved to be a safe procedure with an extremely low complication rate.…”