Mammography with tomosynthesis findings in recurrence cases demonstrated developing asymmetry as the most common feature followed by grouped, amorphous, or pleomorphic microcalcifications with associated asymmetry and/or mass. In contrast, healing scar with fat necrosis exhibited curvilinear and larger calcifications which gradually increase in size in follow up imaging. Ultrasonography revealed ill-defined hypoechoic masses with internal vascularity and ill-defined margins in scar recurrence. In contrast, sharp margins and absence of internal vascularity are noted in post-operative scar changes. Elastography showed increased stiffness with hard areas in scar recurrence, whereas central soft areas were observed in post-operative changes. PET CT and MRI aided in confirming the diagnosis, with increased tracer uptake in recurrent lesions on PET CT and enhancing masses with a type 3 kinetic curve on DCE-MRI. Fat necrosis displayed hyperintense central fat content on T1-weighted images (T1-WI) on MRI, which was crucial in differentiating it from recurrence.

Interesting in case 3 which was an inflammtory pathology, there was an increased tracer uptake on PET CT(FAPI) which had raised a false alarm. However, on subsequent PET-CT, the size of the lesion and tracer uptake have significantly reduced. The reason being, false postive tracer activity may be seen in healing/fibrosing tissue on FAPI PETCT.