There is now official data that COVID vaccines, especially the mRNA ones, can temporarily cause an increase in the size of the lymph nodes. This effect, although transient, may be an impediment to the radiologist who must perform the mammography, as it may not be possible to distinguish these increases in size from any pathological changes in the lymph nodes related to breast cancer.
For this reason, already in March 2021, the Society of Breast Imaging and subsequently also many Screening Centers here in Italy, gave instructions to undergo a mammogram either before the vaccine (second dose and 7o booster) or at least 4-6 weeks later, precisely to do not run into this x-ray picture which could potentially lead the patient to have a second in-depth examination before being able to exclude pathology. If it is not possible to anticipate the vaccine and/or mammography, it is advisable to point out the concomitance of events to the radiologist.