The objective of this study is to analyze magnetic resonance imaging shrinkage pattern of tumor regression after neoadjuvant chemotherapy and to evaluate its relationship with biological subtypes and pathological response. We reviewed the magnetic resonance imaging studies of 51 patients with single mass-enhancing lesions (performed at time 0 and at the II and last cycles of neoadjuvant chemotherapy). Tumors were classified as Luminal A, Luminal B, HER2+, and Triple Negative based on biological and immunohistochemical analysis after core needle biopsy. We classified shrinkage pattern, based on tumor regression morphology on magnetic resonance imaging at the II cycle, as concentric, nodular, and mixed. We assigned a numeric score (0: none; 1: low; 2: medium; 3: high) to the enhancement intensity decrease. Pathological response on the surgical specimen was classified as complete (grade 5), partial (grades 4-3), and non-response (grades 1-2) according to Miller and Payne system. Fisher test was used to relate shrinkage pattern with biological subtypes and final pathological response. Seventeen patients achieved complete response, 25 partial response, and 9 non-response. A total of 13 lesions showed nodular pattern, 20 concentric, and 18 mixed. We found an association between concentric pattern and HER2+ (p < 0.001) and mixed pattern and Luminal A lesions (p < 0.001). We observed a statistical significant correlation between concentric pattern and complete response (p < 0.001) and between mixed pattern and non-response (p = 0.005). Enhancement intensity decrease 3 was associated with complete response (p < 0.001). Shrinkage pattern and enhancement intensity decrease may serve as early response indicators after neoadjuvant chemotherapy. Shrinkage pattern correlates with tumor biological subtypes.

Purpose. Assessing the role of breast MRI compared to galactography in patients with unilateral bloody or serous-bloody nipple discharge. Materials and Methods. Retrospective study including 53 unilateral discharge patients who performed galactography and MRI. We evaluated the capability of both techniques in identifying pathology and distinguishing between nonmalignant and malignant lesions. Lesions BIRADS 1/2 underwent follow-up, while the histological examination after surgery has been the gold standard to assess pathology in lesions BIRADS 3/4/5. The ROC analysis was used to test diagnostic MRI and galactography ability. Results. After surgery and follow-up, 8 patients had no disease (15%), 23 papilloma (43%), 11 papillomatosis (21%), 5 ductal cancer in situ (10%), and 6 papillary carcinoma (11%) diagnoses. Both techniques presented 100% specificity; MRI sensitivity was 98% versus 49% of galactography. Considering MRI, we found a statistical association between mass enhancement and papilloma (P < 0.001; AUC 0.957; CI 0.888–1.025), ductal enhancement and papillomatosis (P < 0.001; AUC 0.790; CI 0.623–0.958), segmental enhancement and ductal cancer in situ (P = 0.007; AUC 0.750; CI 0.429–1.071), and linear enhancement and papillary cancer (P = 0.011). Conclusions. MRI is a valid tool to detect ductal pathologies in patients with suspicious bloody or serous-bloody discharge showing higher sensitivity and specificity compared to galactography.

Breast-oncoplastic surgery, allowing local tumor control and a better cosmetic outcome, is oncologically safe when applied to early-stage breast cancer. Breast cancer recurrence following conservative therapy may occur during the first 5 years after treatment, with a peak incidence after 2 years. Therefore, during the follow-up period, patients undergo a series of ultrasound (US) and mammographic examinations. However, after surgery and radiation therapy, several modifications occur in the treated breast, causing difficulties in image interpretation, especially when local recurrence is suspected. Although not included in routine follow-up, magnetic resonance imaging (MRI) is often used in clinical practice, being considered more sensitive than the conventional imaging examinations in discriminating between postsurgical tissue modifications and tumor recurrence. In this review article, we analyze expected and pathologic breast MRI findings after conservative oncoplastic surgery compared to US and mammographic findings in order to distinguish local recurrence and avoid potential pitfalls in image interpretation.