We determined if specific tumor types of non-small cell lung cancer can be identified by variance in FDG-PET standard uptake value (SUV) in combination with characteristics on CT. Staging FDG-PET and CT scans of 81 patients (34 men and 47 women, average age 67±11 years) with 82 lung cancers were analyzed. Mean tumor SUV was calculated at the location of maximum FDG uptake. Tumor size, margins, and location were analyzed on CT. Statistical analysis compared SUV between tumor subtypes, assessed relationship between tumor subtype and features on CT and determined if combination of CT and SUV patterns predicted tumor type. In total 35 adenocarcinomas (AC); 15 bronchioloalveolar cell carcinomas (BAC), 23 squamous cell carcinomas and 9 large cell carcinomas were evaluated. Significant differences were found between SUV of all AC and squamous cell (p<0.0001); between all AC and large cell (p=0.03); between non-BAC AC and squamous cell types (p=0.0005); BAC and non-BAC AC (p=0.04), BAC and squamous cell (p<0.0001); BAC and large cell (p=0.004). Ground glass was the most significant CT feature in distinguishing tumor types, which was seen in BAC (p<0.0003). In conclusion, SUVs for non-small cell lung cancer were most significantly different between BAC and all other NCLC cell subtypes. The presence of ground glass in a nodule on CT is a significant feature for BAC and should raise the suspicion for this tumor type despite low FDG uptake.

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