The Contribution of Fluorine (18)F-FDG PET/CT to Lung Cancer Diagnosis, Staging and Treatment Planning

OBJECTIVE: Lung cancer is the most common cause of cancer-related death throughout the world, and the correct choice of treatment based on early diagnosis and staging increases the chance of survival. The present study aims to investigate the contribution of fluorine 18-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG PET/CT) to the management of lung cancer. METHODS: In this study, 50 patients who underwent (18)F-FDG PET/CT for lung cancer diagnosis and staging between February 2012 and February 2014 were included. The maximum standardized uptake value (SUV(max)) of the primary lung lesion along with other findings of (18)F-FDG PET/CT and the results of histopathologic and conventional examinations were evaluated retrospectively. The mean survival time of patients was determined, and the findings were compared by using statistical methods. RESULTS: Histopathologic examinations revealed 51 lung cancers in 50 patients. The sensitivity, accuracy and positive predictive value of (18)F-FDG PET/CT in detecting primary malignancy were 94%, 94%, 100%, respectively. Adenocarcinoma (n=23, 16.8±13.5) and squamous cell carcinoma (n=15, 17.9±5.6) did not differ significantly regarding their mean SUV(max) values (p=0.2). A statistically significant positive correlation (r=0.4) was identified between tumor size and SUV(max) value for 51 tumors (p=0.002). The (18)F-FDG PET/CT result was true negative in nine, false positive in six, true positive in two, and false negative in four patients who underwent histopathologic evaluation of their lymph nodes. The (18)F-FDG PET/CT changed treatment planning in 34% of the patients. No significant relationship was identified between SUV(max) value of the tumor and patient survival in patients (p=0.118). CONCLUSION: The present study concluded that PET/CT was an efficient method in the diagnosis and staging of lung cancer since it provided useful information in addition to conventional methods. It was also observed that PET/CT scanning resulted in a change in therapeutic plans in the majority of patients. However, there was no statistically significant relationship between survival and the SUV(max) of the primary mass.