When Would A Breast MRI Show The Non-mass Lesion Decreased In Size Over A Span Of Five Months?

Breast mri 6/22 found nonenhancemnt mass surveillance follow up 11/2022 days the non mass has decreased in size a little. This was a different mri place then the 6/22 mri. My question is the mri from 6/22 reads the non mass is 2cm x .07x 1 cm and the one from 11/22 reads measuring up to 3 cm in greatest anteroposterior dimension I am just confused how it decreased if it was 2 cm before now measuring 3cm