F Moloney1, D Ryan2, L McCarthy3, J McCarthy4, L Burke5, M T Henry6, M P Kennedy7, J Hinchion8, S McSweeney9, M M Maher10, K O'Regan11. 1. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: fiachramoloney@hotmail.com. 2. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: ryansurgeon@gmail.com. 3. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: lauraghmccarthy1@hotmail.com. 4. Department of Pathology, Cork University Hospital, Cork - 0214922000, Ireland. Electronic address: julie.mccarthy@hse.ie. 5. Department of Pathology, Cork University Hospital, Cork - 0214922000, Ireland. Electronic address: louise.burke@hse.ie. 6. Department of Respiratory Medicine, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: michael.henry@hse.ie. 7. Department of Respiratory Medicine, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: marcus.kennedy@hse.ie. 8. Department of Cardiothoracic Surgery, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: John.Hinchion@hse.ie. 9. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: Sean.McSweeny@hse.ie. 10. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: m.maher@ucc.ie. 11. Department of Radiology, Cork University Hospital, Cork - 00353214922000, Ireland. Electronic address: kevin.ORegan1@hse.ie.
Abstract
INTRODUCTION: The aim of this study was to identify radiological factors that may reduce false-positive results and increase diagnostic accuracy when staging the mediastinum of patients with non-small cell lung carcinoma (NSCLC). METHODS: This was a retrospective, interdisciplinary, per-node analysis study. We included patients with NSCLC and mediastinal nodes with an SUV max in the range of 2.5-4.0 on PET-CT. We hypothesized that the greatest number of false positive cases would occur in this cohort of patients. RESULTS: A total of 92 mediastinal lymph nodes were analyzed in 44 patients. Mediastinal disease (N2/N3) was histologically confirmed in 15 of 44 patients and in 34 of 92 lymph nodes; positive predictive value of 37% and false positive rate of 63%. Lymph node SUV max, tumor size, ratio of node SUV max to tumor SUV max (SUVn/SUVp), and ratio of node SUV max to node size (SUV n/SADn) were significantly higher in true positive cases. Using a threshold of 0.3 for SUV node/tumor and 3 for SUV node/size yielded sensitivities of 91% and 71% and specificities of 71% and 69% respectively for the detection of mediastinal disease. Using both ratios in combination resulted in a sensitivity of 65% and a specificity of 88%. Concurrent benign lung disease was observed significantly more frequently in false-positive cases. CONCLUSION: SUVn/SUVpt and SUVn/SADn may be complimentary to conventional visual interpretation and SUV max measurement in the assessment of mediastinal disease in patients with NSCLC.
INTRODUCTION: The aim of this study was to identify radiological factors that may reduce false-positive results and increase diagnostic accuracy when staging the mediastinum of patients with non-small cell lung carcinoma (NSCLC). METHODS: This was a retrospective, interdisciplinary, per-node analysis study. We included patients with NSCLC and mediastinal nodes with an SUV max in the range of 2.5-4.0 on PET-CT. We hypothesized that the greatest number of false positive cases would occur in this cohort of patients. RESULTS: A total of 92 mediastinal lymph nodes were analyzed in 44 patients. Mediastinal disease (N2/N3) was histologically confirmed in 15 of 44 patients and in 34 of 92 lymph nodes; positive predictive value of 37% and false positive rate of 63%. Lymph node SUV max, tumor size, ratio of node SUV max to tumor SUV max (SUVn/SUVp), and ratio of node SUV max to node size (SUV n/SADn) were significantly higher in true positive cases. Using a threshold of 0.3 for SUV node/tumor and 3 for SUV node/size yielded sensitivities of 91% and 71% and specificities of 71% and 69% respectively for the detection of mediastinal disease. Using both ratios in combination resulted in a sensitivity of 65% and a specificity of 88%. Concurrent benign lung disease was observed significantly more frequently in false-positive cases. CONCLUSION: SUVn/SUVpt and SUVn/SADn may be complimentary to conventional visual interpretation and SUV max measurement in the assessment of mediastinal disease in patients with NSCLC.