Abstract
1487
Objectives Breast cancer (BC) is the most common cancer in women in western countries. F18-FDG is a routine imaging technique with an increasing number of women undergoing F18-FDG PET/CT for various cancer or diseases. In this context it is most important not to miss a suspicious uptake pattern which could lead to the incidental finding of BC. This is especially true as there is a physiological activity of the mammary gland in F18-FDG-PET. However, little is known about textural characteristics of normal breast metabolism and its variation according to age. We assessed textural indices (TI) in normal breast tissue according to age to derive reference values that could be subsequently used for identifying suspicious metabolic texture.
Methods A normal breast tissue group (NBT group) was defined from a population of women who underwent a F18-FDG-PET/CT (GE Discovery LS scanner) in our institution for initial staging of various cancers (with no previous history of BC, endometrial, or ovarian cancers). We defined 3 groups of patients: young women 55 ans (O), following the various stages of estrogenic impregnation (childbearing, perimenopause and menopause). SUV (max, mean and peak) and TI (homogeneity, entropy, LRE, SRE, LGZE and HGZE) were measured in Breast Volumes of Interest (B-VOI) drawn on both breasts with an identical volume of 20 mL.
Results 112 women from 20 to 95 yo were included and 224 VOI were drawn: 60 VOI (Y), 40 VOI (M) and 124 (O). The age was significantly different between the groups (p <0.05, Kruskal Wallis test). SUV and TI very significantly differed between the 3 age groups (p >0.05 except for LRE). Overall, metabolic heterogeneity decreased with age together with FDG metabolism.
Conclusions Our study showed significant differences in textural indexes between age groups in non-pathological breast tissue. Those findings should be taken into account to interpret quantitative measurement made in women with suspected lesions. Further investigation should determine whether a specific metabolic texture appears to be an early sign of BC.