A Bustos García de Castro1, J Ferreirós Domínguez2, R Delgado Bolton3, C Fernández Pérez4, B Cabeza Martínez2, M García García-Esquinas2, J L Carreras Delgado5. 1. Servicio de Radiodiagnóstico, Hospital Clínico San Carlos, Madrid, España. Electronic address: abustos.hcsc@salud.madrid.org. 2. Servicio de Radiodiagnóstico, Hospital Clínico San Carlos, Madrid, España. 3. Departamento de Diagnóstico por Imagen y Medicina Nuclear, Hospital de La Rioja, Logroño, España. 4. Instituto de Investigación Sanitaria San Carlos, Universidad Complutense de Madrid, Madrid, España. 5. Servicio de Medicina Nuclear, Hospital Clínico San Carlos, Madrid, España.
Abstract
OBJECTIVE: To assess the importance of false-negative and false-positive findings in computed tomography (CT) and 18F-FDG positron emission tomography (PET) in mediastinal lymph node staging in patients undergoing surgery for non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: This retrospective study included 113 consecutive patients and 120 resected NSCLCs; 22 patients received neoadjuvant treatment. We compared the findings on preoperative 18F-FDG PET-CT studies with the postoperative pathology findings. Lymph node size and primary tumor size were measured with CT, and lymph nodes and primary tumors were evaluated qualitatively and semiquantitatively (using standardized uptake values (SUVmax)) with PET. RESULTS: Metastatic lymph nodes were found in 26 (21.7%) of the 120 tumors and in 41 (7.7%) of the 528 lymph node stations analyzed. 18F-FDG PET-CT yielded 53.8% sensitivity, 76.6% specificity, 38.9% positive predictive value, 85.7% negative predictive value, and 71.7% diagnostic accuracy. The false-negative rate was 14.2%. Multivariable analysis found that the factors associated with false-negative findings were a moderate degree of differentiation in the primary tumor (p = 0.005) and an SUVmax of the primary tumor >4 (p = 0.027). The false-positive rate was 61.1%, and the multivariable analysis found that lymph node size >1cm was associated with false-positive findings (p < 0.001). CONCLUSIONS: In mediastinal lymph node staging in patients with NSCLC, 18F-FDG PET-CT improves the specificity and negative predictive value and helps clinicians to select the patients that will benefit from surgery. Given the high rate of false positives, histological confirmation of positive cases is recommendable.
OBJECTIVE: To assess the importance of false-negative and false-positive findings in computed tomography (CT) and 18F-FDG positron emission tomography (PET) in mediastinal lymph node staging in patients undergoing surgery for non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: This retrospective study included 113 consecutive patients and 120 resected NSCLCs; 22 patients received neoadjuvant treatment. We compared the findings on preoperative 18F-FDG PET-CT studies with the postoperative pathology findings. Lymph node size and primary tumor size were measured with CT, and lymph nodes and primary tumors were evaluated qualitatively and semiquantitatively (using standardized uptake values (SUVmax)) with PET. RESULTS: Metastatic lymph nodes were found in 26 (21.7%) of the 120 tumors and in 41 (7.7%) of the 528 lymph node stations analyzed. 18F-FDG PET-CT yielded 53.8% sensitivity, 76.6% specificity, 38.9% positive predictive value, 85.7% negative predictive value, and 71.7% diagnostic accuracy. The false-negative rate was 14.2%. Multivariable analysis found that the factors associated with false-negative findings were a moderate degree of differentiation in the primary tumor (p = 0.005) and an SUVmax of the primary tumor >4 (p = 0.027). The false-positive rate was 61.1%, and the multivariable analysis found that lymph node size >1cm was associated with false-positive findings (p < 0.001). CONCLUSIONS: In mediastinal lymph node staging in patients with NSCLC, 18F-FDG PET-CT improves the specificity and negative predictive value and helps clinicians to select the patients that will benefit from surgery. Given the high rate of false positives, histological confirmation of positive cases is recommendable.
Authors: Tara Pereiro-Brea; Antonio Golpe-Gómez; Antonio Miguel Golpe-Sánchez; Luís Valdés; Anxo Martínez de Alegría; José Martín Carreira-Villamor; Alberto Ruano-Raviña Journal: Can Respir J Date: 2020-06-05 Impact factor: 2.409