What happened, in summary

A 75-year-old woman had previously received breast-conserving treatment for left ductal carcinoma in situ. Three years later, annual imaging of the opposite breast found a 6 mm irregular mass at the 1 o’clock position of the right breast. Biopsy showed grade II invasive ductal carcinoma that was ER-positive, PR-positive, and HER2-equivocal.

She underwent right lumpectomy with placement of a BioZorb marker, and sentinel-node biopsy was negative. Postoperative radiation followed, with imaging surveillance every six months.

Three years after right lumpectomy, mammography and ultrasound identified a new 3 mm mass medial to the BioZorb site. Biopsy confirmed grade II invasive ductal carcinoma that remained ER-positive and PR-positive and was HER2-negative. A separate asymmetry behind the BioZorb could not be fully assessed by ultrasound because of shadowing from the device and scar tissue. MRI showed a suspicious 2.0 cm mass in that region, and stereotactic biopsy confirmed another site of disease.

With recurrent cancer documented at two sites in the right breast, she underwent right mastectomy. The structured record centers on the right invasive cancer and recurrence; the earlier left DCIS is included only as clinical context.