P1-096: 18Fluorodeoxyglucose Positron Emission Tomography in the diagnosis and staging of lung cancer: a systematic review and practitioner guideline in Ontario, Canada

Abstract

S588evaluate whether the value of SUVmax and RI can diagnose as lung cancer or the presence of lymph node metastasis. Results: Eighty-one patients were diagnosed as lung cancer and the median SUVmax was 9.2 (range, 0.8 to 24). Ten patients were diagnosed as benign nodules and the median SUVmax was 3.1 (range, 1.6 to 8.9). There was a significant difference of SUVmax between lung cancer and benign tumor (p<0.001). The correlation between tumor size in lung cancer and SUVmax were recognized (r=0.67). If the cutoff value of SUVmax was 3.5 or greater to depict malignant tumors, the sensitivity and specificity in all pulmonary nodules were 84% and 80%. The sensitivity and specificity in tumors more than 3cm in diameter were 98% and 100%. On the other hand, in tumors less than 3cm in diameter, the sensitivity and specificity were 48% and 86%. However, if the tumor with either RI of more than 10% or SUVmax of more than 3.5 is classified as lung cancer, the sensitivity and specificity was 83% and 86% in tumors less than 3cm in diameter. Four hundred and sixty lymph nodes of the hilum and the mediastinum were dissected. Twentyone of those were metastatic lymph nodes (4.6%). If the lymph nodes with 1cm or greater in minor diameter at the chest CT scan are judged with metastasis, the sensitivity, specificity and accuracy were 50%, 97% and 33%, respectively. Whereas if the cut-off value of SUVmax is 3.5 or greater to depict lymph node metastasis at FDG-PET/CT, the sensitivity, specificity and accuracy were 80%, 99% and 76%, respectively. There were 14 false-positive lymph nodes at the chest CT scan and 5 false-positive ones at FDG-PET/CT. Conclusion:In the tumors more than 3 cm in diameter, the value of SUVmax was a very useful tool for diagnosis of lung cancer. However, in the tumors less than 3 cm in diameter, the value of RI in addition to SUVmax was useful for diagnosis. FDG-PET/CT was significantly better than the chest CT scan for diagnosis of lymph node metastasis.