PURPOSE Breast-conserving therapy (BCT) is the preferred treatment for unifocal breast cancer (BC). The oncologic safety of BCT for multiple ipsilateral breast cancer (MIBC) has not been demonstrated in a prospective study. ACOSOG Z11102 (Alliance) is a phase II, single-arm, prospective trial designed to evaluate oncologic outcomes in patients undergoing BCT for MIBC. PATIENTS AND METHODS Women age 40 years and older with two to three foci of biopsy-proven cN0-1 BC were eligible. Patients underwent lumpectomies with negative margins followed by whole breast radiation with boost to all lumpectomy beds. The primary end point was cumulative incidence of local recurrence (LR) at 5 years with an a priori rate of clinical acceptability of <8%. RESULTS Among 270 women enrolled between November 2012 and August 2016, there were 204 eligible patients who underwent protocol-directed BCT. The median age was 61 years (range, 40-87 years). At a median follow-up of 66.4 months (range, 1.3-90.6 months), six patients developed LR for an estimated 5-year cumulative incidence of LR of 3.1% (95% CI, 1.3 to 6.4). Patient age, number of sites of preoperative biopsy–proven BC, estrogen receptor status and human epidermal growth factor receptor 2 status, and pathologic T and N categories were not associated with LR risk. Exploratory analysis showed that the 5-year LR rate in patients without preoperative magnetic resonance imaging (MRI; n = 15) was 22.6% compared with 1.7% in patients with a preoperative MRI (n = 189; P = .002). CONCLUSION The Z11102 clinical trial demonstrates that breast-conserving surgery with adjuvant radiation that includes lumpectomy site boosts yields an acceptably low 5-year LR rate for MIBC. This evidence supports BCT as a reasonable surgical option for women with two to three ipsilateral foci, particularly among patients with disease evaluated with preoperative breast MRI.
Abstract GS4-01: Impact of Breast Conservation Therapy on Local Recurrence in Patients with Multiple Ipsilateral Breast Cancer – Results from ACOSOG Z11102 (Alliance)
Abstract Background Breast conserving therapy (BCT) is accepted as a preferred option for unifocal breast cancer. However, the oncologic safety of BCT for multiple ipsilateral breast cancer (MIBC), has not been demonstrated in a prospective study. The ACOSOG (Alliance) Z11102 phase II single arm prospective trial was designed to evaluate outcomes with BCT for MIBC. Methods Women age 40+ with 2 or 3 foci of biopsy proven breast cancer (BC) (each site < 5cm in size with at least 1 site invasive) separated by >2-3 cm of normal breast tissue and disease limited to two quadrants of the breast with cN0 or cN1 disease were eligible. All patients had pre-operative mammogram and breast MRI was initially required and subsequently made optional. Neoadjuvant therapy was not allowed. Patients were treated with lumpectomy resected to negative margins followed by whole breast radiation with boost to all lumpectomy beds. The primary endpoint of Z11102 is the cumulative incidence of local recurrence (LR, defined as histologic evidence of ductal carcinoma in situ or invasive BC in the ipsilateral breast or chest wall) at 5 years (treating death and distant and nodal/regional recurrence as competing risks) to assess whether the rate is greater than 8%. Data were frozen 5/25/2022. Results From 11/2012-8/2016, 270 women were enrolled. Of these, 33 were ineligible, 14 converted to mastectomy, 11 were unable to meet protocol-specific radiation endpoints, 1 had no definable tumor, 1 had 4 sites of cancer and 16 withdrew before completing surgery and radiation, leaving 194 patients [median age 61 (range 40-87)] eligible who completed breast conserving surgery and radiation therapy. With median follow-up of alive patients of 66.6 months (range: 4.1, 90.6), 6 patients have developed LR (5 ipsilateral breast and 1 chest wall), corresponding to an estimated cumulative incidence of local recurrence of 3.2% (95% CI: 1.3, 6.4) at 5 years. No patients have developed regional recurrence, 5 patients developed distant recurrence, 0 patients developed local and distant recurrence, 5 patients developed contralateral BC, 3 new non-BC primaries and 8 patients have died (1 related to BC). The rate of local recurrence in patients without a breast pre-op MRI (n=14) was 22.6% at 5 years compared to 1.7% among the 180 patients with a preop MRI (p=0.002). Patient age, number of sites of preoperative biopsy proven BC, HER2 status, pathologic T and N category were not statistically significantly associated with risk of LR. Conclusion The Z11102 clinical trial demonstrates that for women with MIBC breast conserving surgery with adjuvant radiation with lumpectomy site boosts has an acceptably low LR rate (3.2% at 5 years), making this a reasonable consideration for women with 2-3 ipsilateral foci. The LR rate was significantly higher in the small cohort of patients without preoperative breast MRI. Support: U10CA180821, U10CA180882; https://acknowledgments.alliancefound.org. ClinicalTrials.gov Identifier: NCT01556243 Table 1: Factors associated with LR after BCT for MIBC Citation Format: Judy C. Boughey, Kari M. Rosenkranz, Karla V. Ballman, Linda McCall, Bruce G. Haffty, Laurie W. Cuttino, Charlotte D. Kubicky, H. T. Carisa Le-Petross, Kimberly Van Zee, Armando E. Giuliano, Olwen M. Hahn, Kelly K. Hunt, Lisa Carey, Ann Partridge. Impact of Breast Conservation Therapy on Local Recurrence in Patients with Multiple Ipsilateral Breast Cancer – Results from ACOSOG Z11102 (Alliance) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS4-01.
Breast-Gynaecological & Immuno-Oncology International Cancer Conference (BGICC) Consensus and Recommendations for the Management of Triple-Negative Breast Cancer
Background: The management of patients with triple-negative breast cancer (TNBC) is challenging with several controversies and unmet needs. During the 12th Breast-Gynaecological & Immuno-oncology International Cancer Conference (BGICC) Egypt, 2020, a panel of 35 breast cancer experts from 13 countries voted on consensus guidelines for the clinical management of TNBC. The consensus was subsequently updated based on the most recent data evolved lately. Methods: A consensus conference approach adapted from the American Society of Clinical Oncology (ASCO) was utilized. The panellists voted anonymously on each question, and a consensus was achieved when ≥75% of voters selected an answer. The final consensus was later circulated to the panellists for critical revision of important intellectual content. Results and conclusion: These recommendations represent the available clinical evidence and expert opinion when evidence is scarce. The percentage of the consensus votes, levels of evidence and grades of recommendation are presented for each statement. The consensus covered all the aspects of TNBC management starting from defining TNBC to the management of metastatic disease and highlighted the rapidly evolving landscape in this field. Consensus was reached in 70% of the statements (35/50). In addition, areas of warranted research were identified to guide future prospective clinical trials.
FOXC1 identifies basal-like breast cancer in a hereditary breast cancer cohort
Purpose The seventh edition of the American Joint Committee on Cancer (AJCC) staging system for breast cancer differentiates patients with T1 tumors and lymph node micrometastases (stage IB) from patients with T1 tumors and negative nodes (stage IA). This study was undertaken to determine the utility of the stage IB designation. Patients and Methods The following two cohorts of patients with breast cancer were identified: 3,474 patients treated at The University of Texas MD Anderson Cancer Center from 1993 to 2007 and 4,590 patients from the American College of Surgeons Oncology Group (ACOSOG) Z0010 trial. Clinicopathologic and outcomes data were recorded, and disease was staged according to the seventh edition AJCC staging system. Recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) were determined using the Kaplan-Meier method and compared using the log-rank test. Results Median follow-up times were 6.1 years and 9.0 years for the MD Anderson Cancer Center and ACOSOG cohorts, respectively. In both cohorts, there were no significant differences between patients with stage IA and stage IB disease in 5- or 10-year RFS, DSS, or OS. Estrogen receptor (ER) status and grade significantly stratified patients with stage I disease with respect to RFS, DSS, and OS. Conclusion Among patients with T1 breast cancer, individuals with micrometastases and those with negative nodes have similar survival outcomes. ER status and grade are better discriminants of survival than the presence of small-volume nodal metastases. In preparing the next edition of the AJCC staging system, consideration should be given to eliminating the stage IB designation and incorporating biologic factors.
Radiation Field Design in the ACOSOG Z0011 (Alliance) Trial
Purpose ACOSOG Z0011 established that axillary lymph node dissection (ALND) is unnecessary in patients with breast cancer with one to two positive sentinel lymph nodes (SLNs) who undergo lumpectomy, radiotherapy (RT), and systemic therapy. We sought to ascertain RT coverage of the regional nodes in that trial. Methods We evaluated case report forms completed 18 months after enrollment. From 2012 to 2013, we collected all available detailed RT records for central review. Results Among 605 patients with completed case report forms, 89% received whole-breast RT. Of these, 89 (15%) were recorded as also receiving treatment to the supraclavicular region. Detailed RT records were obtained for 228 patients, of whom 185 (81.1%) received tangent-only treatment. Among 142 with sufficient records to evaluate tangent height, high tangents (cranial tangent border ≤ 2 cm from humeral head) were used in 50% of patients (33 of 66) randomly assigned to ALND and 52.6% (40 of 76) randomly assigned to SLND. Of the 228 patients with records reviewed, 43 (18.9%) received directed regional nodal RT using ≥ three fields: 22 in the ALND arm and 21 in the SLND arm. Those receiving directed nodal RT had greater nodal involvement (P < .001) than those who did not. Overall, there was no significant difference between treatment arms in the use of protocol-prohibited nodal fields. Conclusion Most patients treated in Z0011 received tangential RT alone, and some received no RT at all. Some patients received directed nodal irradiation via a third field. Further research is necessary to determine the optimal RT approach in patients with low-volume axillary disease treated with SLND alone.
Personalizing Breast Cancer Staging by the Inclusion of ER, PR, and HER2