FDG-PET/CT imaging in assessing mucin-producing non-small cell lung cancer with pathologic correlation

Objective: The objective of this study was to describe the PET/CT findings of mucin-producing non-small cell lung cancer (NSCLC) and how those findings are associated with pathology. Methods: A review of all patients with FDG-PET/CT identified 11 patients with histopathologically confirmed mucin-producing NSCLC; 3 mucinous bronchioloalveolar carcinoma (mBAC), 5 mixed-type adenocarcinoma with prominent mucinous BAC pattern (ADENO + mBAC), and 3 mixed-type adenocarcinoma with mucin production (ADENO + MUCIN) in our institute. Results: Among 11 patients, only 2 lesions (18%) evidenced positive PET results for standardized uptake value (SUV) of 3.5 (by ROC analysis) whereas all cases were detected correctly at CT. The mean SUV was 2.0 in the 9 lesions not detected and 2.5 in all cases. The mean SUV of pure mBAC was 1.93, that of mucin-producing adenocarcinoma was 2.69 without a significant difference (p = 0.279). No significant correlations between tumor size or stage and SUV were determined. Conclusions: PET/CT for SUV is limited in the detection of mucin-producing NSCLC. Therefore, the CT component of PET/CT may allow for significantly improved sensitivity and help to reduce delayed diagnose. The SUV in mBACs were lower than the other types of mucin-producing adenocarcinoma; however, we determined no significant difference to exist between the SUVs of two groups of lung cancer.