Usefulness of magnetic resonance in patients with invasive cancer eligible for breast conservation: a comparative study.

BACKGROUND: The role of magnetic resonance imaging (MRI) in newly detected breast cancer remains controversial. We investigated the impact of preoperative MRI on surgical management of infiltrating breast carcinoma (IBC). METHODS: We reviewed data of 237 patients with IBC who were suitable for breast-conserving surgery (BCS) between 2009 and 2011. Of these patients, 109 underwent preoperative MRI (46%; MRI group) and 128 did not (54%; no-MRI group). We analyzed MRI-triggered changes in surgical plan and compared differences in rates of positive margins and mastectomy. RESULTS: Tumor size was larger in the MRI group (16.8 mm vs. 13.9 mm; P < .001). MRI changed the initial surgical planning in 18 of 109 patients (16.5%) because of detection of larger tumor diameter requiring wider resection (8 patients [7.3%]) or additional malignant lesions in the ipsilateral (9 patients [8.2%]) or contralateral breast (1 patient [0.9%]). MRI-triggered treatment changes included mastectomy (n = 12), wider excision (n = 5), and contralateral BCS (n = 1). Reoperation rates for positive margins after BCS appeared higher in the no-MRI group (4.1% vs. 8.6%), but the difference missed statistical significance (P = .9). Overall mastectomy rates were higher in the MRI group (13.7% vs. 7.0%; P < .05). The likelihood of having a change of treatment resulting from MRI was significantly higher for patients with tumors > 15 mm and for those with positive lymph nodes. CONCLUSION: Lymph node positivity and tumor size > 15 mm may predict an MRI-triggered change in surgical plan. Preoperative MRI resulted in higher mastectomy rates justified by biopsy-proven additional foci of carcinoma and did not significantly reduce reoperation rates for positive margins.

Sentinel node biopsy in early breast cancer: lessons learned from more than 1000 cases at a single institution.

AIMS: The aims of this paper are to report the development of sentinel node biopsy (SNB) in breast cancer at a single institution and to discuss the relevant issues on SNB still to be elucidated. PATIENTS AND METHODS: From 1998 to 2010, 1021 SNBs with frozen section examination were carried out in patients with breast cancer. In the early period (1998-2002) SNB was always combined with axillary lymph node dissection (ALND). From 2002 onwards, only patients with a positive SNB result underwent ALND (late period). The characteristics of patients with infiltrating carcinoma (IC) and ductal carcinoma in situ (DCIS) and the histological status of the sentinel nodes were examined. The survival outcomes of node-negative patients were compared between patients submitted to SNB and ALND (ALND group) during the early period and patients who underwent only SNB during the late period (SNB group). RESULTS: The sentinel node was identified intraoperatively in 98.3% of cases. During the early period the overall accuracy of SNB was 97.0%. During the late period, 700 patients with IC and 140 with DCIS underwent SNB. In the IC group, 149 patients (21.3%) had sentinel node macrometastases and 36 (5.1%) micrometastases; of that subgroup, 21 underwent ALND and no other metastatic lymph nodes were found, and 15 underwent SNB only. Axillary recurrences were observed in 4 patients (0.77%) with negative SNB; none of these were among the patients with micrometastatic SNB. Two patients (1.4%) with DCIS had a positive SNB. In node-negative patients the 5-year overall survival was 96.7% in the ALND group and 96.5% in the SNB group (P = 0.63). The 5-year disease-free survival was 93.8% and 93.2% in the ALND and SNB groups, respectively (P = 0.77). CONCLUSIONS: Overall and disease-free survival in patients with a negative SNB result and no further axillary surgery were equal to those in patients with negative ALND. Intraoperative assessment of the sentinel node in expert hands has a low false-negative rate and allows immediate ALND in patients with sentinel node metastases, avoiding the need for a second operation. ALND for sentinel node micrometastases may be safely omitted in most patients with early stage breast cancer.