Defining the Need for Imaging and Biopsy After Mastectomy

Background The proportion of patients eligible for breast-conservation therapy (BCT) yet opting for mastectomy is increasing. This decision is often driven by the desire to eliminate future screening and/or biopsy of the remaining breast or breasts. This study investigated the incidence of post-mastectomy imaging and biopsy. Methods A retrospective review of all unilateral mastectomy (UM) and bilateral mastectomy (BM) cases managed at a single institution was undertaken. Post-mastectomy imaging and biopsy rates were determined. Results Between 2009 and 2015, 185 UM and 200 BM cases managed for breast cancer were identified. The mean follow-up period was 30 months (range 3–75 months). For the patients with UM, imaging studies and biopsies done on the contralateral side were excluded given the standard of care for continued surveillance of the contralateral breast. Of the 185 UM patients, 19 (10%) underwent ipsilateral imaging (all ultrasounds) for physical examination findings, 11 (6%) underwent biopsy, and 2 (1%) had malignant findings. Of the 200 BM patients, 31 (15.5%) required imaging (29 ultrasounds and 2 MRIs), with 76% of the ultrasounds performed on the side with previous cancer. Subsequently, 16 (8%) of the BM patients had biopsy, with 11 (69%) of the 16 biopsies performed on the ipsilateral side. Three (1.5%) of the biopsies done on ipsilateral side demonstrated malignancy, whereas all the contralateral biopsies were benign. Conclusions For 10–15.5% of patients who undergo mastectomy, either UM or BM, subsequent imaging is required, whereas 6–8% undergo biopsy. The yield of malignancy is low, approximately 1%. Thus, after mastectomy, the need for imaging and biopsy is not eliminated. This information is critical for patient understanding and expectation related to surgical decision making.