The ability to accurately diagnose mediastinal lymph node involvement is significantly important in patients with nonsmall cell lung cancer (NSCLC). Positron emission tomography (PET) imaging has become a standard technique to assess lymph node involvement in patients with NSCLC. The purpose of this study is to evaluate the accuracy of PET scan imaging as a mediastinal staging tool in patients with NSCLC at our regional teaching institution. We performed a single-institution, retrospective review of patients diagnosed with NSCLC from January 1, 2006, through December 31, 2007. We included only those patients who underwent computed tomography (CT), PET, and pathologic assessment of mediastinal lymph nodes. Using pathologic assessment as the criterion standard, the overall accuracy, sensitivity, specificity, and positive and negative predictive values of CT and PET were calculated. One hundred seventeen patients were identified for inclusion in the study. The overall accuracy was 81.2 per cent for CT and 91.5 per cent for PET. Sensitivity was 42.1 per cent for CT and 52.6 per cent for PET. Specificity was 88.8 per cent for CT and 99.0 per cent for PET. Positive predictive values were 42.1 per cent for CT and 90.9 per cent for PET; negative predictive values were 88.8 per cent for CT and 91.5 per cent for PET. False-negative result rates were 9.4 per cent for CT and 7.7 per cent for PET; false-positive result rates were 9.4 per cent for CT and 0.9 per cent for PET. Our analysis confirms the use of PET scan imaging in the staging of patients with NSCLC at a regional teaching institution.
Small tumor of the medial breast presenting with a contralateral lymph node involvement detected on positron emission tomography scan