Screening for breast cancer has been realised as alarge-scale research in Europe and North Americawith effective diagnostic and clinical results. The ۱obvious reason for performing and encouragingscreening is to reduce the incidence of mortality.Breast screening has been demonstrated to prolonglives; however, over-diagnosis is still a clinicalproblem. Despite screening procedures, the ۲available data reporting incidental breast uptake,revealed by F-۱۸-fluoro-fluorodeoxygulose positronemission tomography/computed tomography(FDG-PET/CT) in patients studied for nonbreastrelated oncologic purposes, suggest that somelesions are still missed during traditional screeningwork-up. Breast incidentaloma could be defined as abreast lesion incidentally and newly detected byimaging techniques performed for an unrelatedpurpose and particularly not for oncologic breastdiseases. Incidental focal FDG uptakes arerelatively frequent and could involve prostate,thyroid, bowel and colon, and pituitary gland. It is ۳-۹generally accepted that whole-body FDG-PET/CTshould not be recommended for primary breastcancer detection or early stage breast cancerevaluation, respectively, because of high falsenegativerates in presence of small lesions, and forcost-effectiveness concerns considering the lowprobability of secondary lesions. In fact, it is oflimited utility in the detection of small (less than۱cm) primary breast tumors. Newer-generation PETscanners with advanced crystal technologies havetheoretically improved resolutions down to ۳ mm atFWHM; however, these resolutions still do notmatch the spatial resolutions of the current screeningtechniques of mammography and ultrasonographyor magnetic resonance. As a consequence, FDGPET/CT is not appropriate as a screening procedure.However, the results derived from literature analysisgive new insight on its possible role in detectingclinically unsuspected small lesions in an earlystage. On the other hand, - / shows a ۱۰ FDG PET CTsignificant added value and can be an effective tool inthe detection of loco-regional recurrence andmetastases in locally advanced breast cancer.