Pathological Analysis of Non-cancerous Lesion in Breast with Abnormal FDG Absorption in 18F-FDG PET/CT Test

Abstract

18F-fluorodeoxyglucose (FDG) positron emission tomography/computed
tomography (PET/CT) (18F-FDG-PET/CT) is a sensitive molecular imaging modality capable of diagnosing breast cancer by means of increased FDG uptake in growing cancer cells. FDG uptake within cells mainly depends on cellular metabolic activity and the number of glucose transporters. However, this mechanism is not specific to cancer cells, for FDG can accumulate in inflammatory cells and benign processes causing false-positive findings. In this study, we analyzed the non-cancerous lesion diagnosed by histology which showed abnormal absorption of FDG in 18F-FDG PET/CT test and demonstrated the image feature of these cases. We undertook a retrospective review of data from 373 women who had an 18F-FDG PET/CT test and analyzed the false positive results in 48 cases according to final pathological results between January 2016 and April 2018. Among these cases, 296 showed abnormal FDG
absorption and were histological diagnosed after surgery. Of 296 patients, who had abnormal FDG absorption, 248 cases were histological diagnosed with breast carcinoma. Fibroadenoma and purulent inflammation accounted for 33.3% and 35.4% of all 48 non-cancerous cases following by intraductal papilloma with the incident of 12.5%. In purulent inflammation cases the max diameter of tumor showed significantly larger than others (P<0.05), and the max diameter of lesion in other diseases showed no significantly differences. 18F-FDG PET/CT results showed that the value of SUVmax in purulent inflammation was significantly higher than that in other diseases (P<0.05) and adenomyoepithelioma, cyst with ductal ectasia and adenosis were showed with a lower SUVmax (P<0.05). In conclusion, despite the low false positive rate 18F-FDG PET/CT is of great value for preoperative evaluation of breast lesion. In
the non-cancerous cases which had an indication of carcinoma in 18F-FDG PET/CT test, the most common diagnosis were fibroadenoma, purulent inflammation and intraductal papilloma.