Role of short-term follow-up magnetic resonance imaging in the detection of post-operative residual breast cancer

The aim of the present study was to evaluate the role of short-term follow-up magnetic resonance imaging (MRI) in the detection of postoperative residual breast cancer. A retrospective analysis was performed on 10 patients who were diagnosed with non-malignant breast lesions by preoperative clinical, ultrasound and mammography examinations and intraoperative frozen-section pathology. These patients were finally confirmed as having malignant breast lesions by paraffin-embedded tissue histology and corresponding received second surgeries. Routine MRI, enhancement MRI and echo-planar imaging-diffusion-weighted imaging were performed on the 10 patients within 1 month after the first surgery. All the cases showed a local distortion of mammary architecture revealed by routine MRI and enhancement MRI images. The enhancement characteristics of the 10 cases were as follows: 3 cases featured stippled enhancement, 2 had small nodular enhancement, 1 showed dendritic enhancement, 1 had a ring-shaped enhancement of the cystic wall and 3 had no abnormal enhancement. The lesions of 7 cases had a type-I enhancement curve (progressive enhancement pattern) and 3 cases had a type-II curve (plateau pattern). The lesions of 4 cases had a decreased apparent diffusion coefficient. In total, 4 cases of tumor residue were diagnosed by MRI and the second pathological examination, while in 1 case the tumor residue was misdiagnosed by MRI but confirmed by the second pathological examination. In conclusion, the present study suggested that short-term follow-up MRI may be of value in the diagnosis of postoperative residual breast tumors and may be helpful for surgeons to develop an accurate surgical plan.