Preliminary study of 18F-FDG PET-CT in defining lymph node radiation target volume for non-small-cell lung cancer patients / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the value of 18F-FDG PET-CT in detecting metastatic lymph node and radiation planning for patient with non-small-cell lung cancer (NSCLC).</p><p><b>METHODS</b>The data of 58 NSCLC patients were retrospectively analyzed. Preoperatively, Both 18F-FDG PET-CT and CT scan were performed for all patients. Blinded interpretation of these images was then carried out. The gross tumor volume defined by radiation oncologist based on imaging results of either PET-CT or CT alone was compared with pathological results eventually.</p><p><b>RESULTS</b>The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of detecting metastatic lymph node in the mediastinum was 56.0%, 54.2%, 54.8%, 38.9%, 70.3% by CT alone, and 88.0%, 85.4%, 86.3%, 75.9%, 93.2% by PET-CT, respectively. There was a statisticalty significant difference between two methods(P < 0.05). However, statisticalty no significant difference in detecting hilar lymph nodes was observed. The radiation target volume defined by CT was identical to that by PET-CT in 31(53.5%) cases, but changed in the other 27 (46.5%) cases when 18F-FDG PET data was added. The accuracy was 75.9% in detecting metastatic lymph nodes in the radiation target volume defined by PET-CT, while it was much lower by CT alone (48.3%) with a statistically significant difference between two methods (P < 0.05).</p><p><b>CONCLUSION</b>18F-FDG PET-CT is more accurate than CT alone in assessment of mediastinal lymph nodes for NSCLC patients. It may be recommended as a method in defining the radiation target volume.</p>