Clinical Utility of Universal Germline Genetic Testing for Patients With Breast Cancer

IMPORTANCE

National Comprehensive Cancer Network guidelines currently recommend germline testing for high-risk genes in selected patients with breast cancer. The clinical utility of recommending testing all patients with breast cancer with multigene panels is currently under consideration.

OBJECTIVE

To examine the implications of universal testing of patients with breast cancer with respect to clinical decision-making.

DESIGN, SETTING, AND PARTICIPANTS

Patients from a previously reported cohort were assessed as in-criteria or out-of-criteria according to the 2017 guidelines and underwent testing with a multigene germline panel between 2017 to 2018. Patients were women and men aged 18 to 90 years, with a new and/or previous diagnosis of breast cancer who had not undergone either single or multigene testing. Clinicians from 20 community and academic sites documented patient clinical information and changes to clinical recommendations made according to test findings. Association between prevalence of pathogenic or likely pathogenic germline variants and previously unreported clinical features, including scores generated by the BRCAPRO statistical model, was determined. Data were analyzed from April 2020 to May 2022.

EXPOSURE

New and/or previous diagnosis of breast cancer.

MAIN OUTCOMES AND MEASURES

Disease management recommendations that were changed as a result of genetic testing results are reported.

RESULTS

Clinicians were asked to assess changes to clinical management as a result of germline genetic testing for 952 patients. Informative clinician-reported recommendations were provided for 939 (467 in-criteria and 472 out-of-criteria) of the patients with breast cancer (936 [99.7%] female; 702 [74.8%] White; mean [SD] age at initial diagnosis, 57.6 [11.5] years). One or more changes were reported for 31 of 37 (83.8%) in-criteria patients and 23 of 34 (67.6%) out-of-criteria patients with a pathogenic or likely pathogenic variant. Recommendations were changed as a result of testing results for 14 of 22 (63.6%) out-of-criteria patients who had a variant in a breast cancer predisposition gene. Clinicians considered testing beneficial for two-thirds of patients with pathogenic or likely pathogenic variants and for one-third of patients with either negative results or variants of uncertain significance. There was no difference in variant rate between patients meeting the BRCAPRO threshold (≥10%) and those who did not (P = .86, Fisher exact test). No changes to clinical recommendations were made for most patients with negative results (345 of 349 patients [98.9%]) or variants of uncertain significance (492 of 509 patients [96.7%]).

CONCLUSIONS AND RELEVANCE

In this cohort study, germline genetic testing was used by clinicians to direct treatment for most out-of-criteria patients with breast cancer with pathogenic or likely pathogenic germline variants, including those with moderate-risk variants. Universal germline testing informs clinical decision-making and provides access to targeted treatments and clinical trials for all patients with breast cancer.

Therapeutic Value of Sentinel Lymph Node Biopsy in Patients With Melanoma: A Randomized Clinical Trial

Importance

Sentinel lymph node (SLN) biopsy is a standard staging procedure for cutaneous melanoma. Regional disease control is a clinically important therapeutic goal of surgical intervention, including nodal surgery.

Objective

To determine how frequently SLN biopsy without completion lymph node dissection (CLND) results in long-term regional nodal disease control in patients with SLN metastases.

Design, Setting, and Participants

The second Multicenter Selective Lymphadenectomy Trial (MSLT-II), a prospective multicenter randomized clinical trial, randomized participants with SLN metastases to either CLND or nodal observation. The current analysis examines observation patients with regard to regional nodal recurrence. Trial patients were aged 18 to 75 years with melanoma metastatic to SLN(s). Data were collected from December 2004 to April 2019, and data were analyzed from July 2020 to January 2022.

Interventions

Nodal observation with ultrasonography rather than CLND.

Main Outcomes and Measures

In-basin nodal recurrence.

Results

Of 823 included patients, 479 (58.2%) were male, and the mean (SD) age was 52.8 (13.8) years. Among 855 observed basins, at 10 years, 80.2% (actuarial; 95% CI, 77-83) of basins were free of nodal recurrence. By univariable analysis, freedom from regional nodal recurrence was associated with age younger than 50 years (hazard ratio [HR], 0.49; 95% CI, 0.34-0.70; P < .001), nonulcerated melanoma (HR, 0.36; 95% CI, 0.36-0.49; P < .001), thinner primary melanoma (less than 1.5 mm; HR, 0.46; 95% CI, 0.27-0.78; P = .004), axillary basin (HR, 0.61; 95% CI, 0.44-0.86; P = .005), fewer positive SLNs (1 vs 3 or more; HR, 0.32; 95% CI, 0.14-0.75; P = .008), and SLN tumor burden (measured by diameter less than 1 mm [HR, 0.39; 95% CI, 0.26-0.60; P = .001] or less than 5% area [HR, 0.36; 95% CI, 0.24-0.54; P < .001]). By multivariable analysis, younger age (HR, 0.57; 95% CI, 0.39-0.84; P = .004), thinner primary melanoma (HR, 0.40; 95% CI, 0.22-0.70; P = .002), axillary basin (HR, 0.55; 95% CI, 0.31-0.96; P = .03), SLN metastasis diameter less than 1 mm (HR, 0.52; 95% CI, 0.33-0.81; P = .007), and area less than 5% (HR, 0.58; 95% CI, 0.38-0.88; P = .01) were associated with basin control. When looking at the identified risk factors of age (50 years or older), ulceration, Breslow thickness greater than 3.5 mm, nonaxillary basin, and tumor burden of maximum diameter of 1 mm or greater and/or metastasis area of 5% or greater and excluding missing value cases, basin disease-free rates at 5 years were 96% (95% CI, 88-100) for patients with 0 risk factors, 89% (95% CI, 82-96) for 1 risk factor, 86% (95% CI, 80-93) for 2 risk factors, 80% (95% CI, 71-89) for 3 risk factors, 61% (95% CI, 48-74) for 4 risk factors, and 54% (95% CI, 36-72) for 5 or 6 risk factors.

Conclusions and Relevance

This randomized clinical trial was the largest prospective evaluation of long-term regional basin control in patients with melanoma who had nodal observation after removal of a positive SLN. SLN biopsy without CLND cleared disease in the affected nodal basin in most patients, even those with multiple risk factors for in-basin recurrence. In addition to its well-validated value in staging, SLN biopsy may also be regarded as therapeutic in some patients.

Trial Registration

ClinicalTrials.gov Identifier: NCT00297895.

Genomic Classification of HER2-Positive Patients With 80-Gene and 70-Gene Signatures Identifies Diversity in Clinical Outcomes With HER2-Targeted Neoadjuvant Therapy

The prospective Neoadjuvant Breast Registry Symphony Trial compared the 80-gene molecular subtyping signature with clinical assessment by immunohistochemistry and/or fluorescence in situ hybridization in predicting pathologic complete response (pCR) and 5-year outcomes in patients with early-stage breast cancer.

Rates of pathogenic variants in common cancer genes among different racial/ethnic groups

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Withdrawal Notice: Abstract 10151 by Beitsch et al, entitled "Rates of pathogenic variants in common cancer genes among different racial/ethnic groups," was withdrawn by the authors from presentation and publication. As they were preparing for presentation at the meeting, the authors discovered additional data that potentially altered the abstract's conclusions.

The abstract was withdrawn on May 13, 2022.

Distinct Neoadjuvant Chemotherapy Response and 5-Year Outcome in Patients With Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Breast Tumors That Reclassify as Basal-Type by the 80-Gene Signature

The 80-gene molecular subtyping signature (80-GS) reclassifies a proportion of immunohistochemistry (IHC)-defined luminal breast cancers (estrogen receptor–positive [ER+], human epidermal growth factor receptor 2–negative [HER2–]) as Basal-Type. We report the association of 80-GS reclassification with neoadjuvant treatment response and 5-year outcome in patients with breast cancer.

Identity exposed: genomic assay unmasks TNBC-like breast cancer tumors disguised as HR+ #NBRST

Age-Independent Preoperative Chemosensitivity and 5-Year Outcome Determined by Combined 70- and 80-Gene Signature in a Prospective Trial in Early-Stage Breast Cancer

BACKGROUND

The Neoadjuvant Breast Symphony Trial (NBRST) demonstrated the 70-gene risk of distant recurrence signature, MammaPrint, and the 80-gene molecular subtyping signature, BluePrint, precisely determined preoperative pathological complete response (pCR) in breast cancer patients. We report 5-year follow-up results in addition to an exploratory analysis by age and menopausal status.

METHODS

The observational, prospective NBRST (NCT01479101) included 954 early-stage breast cancer patients aged 18-90 years who received neoadjuvant chemotherapy and had clinical and genomic data available. Chemosensitivity and 5-year distant metastasis-free survival (DMFS) and overall survival (OS) were assessed. In a post hoc subanalysis, results were stratified by age (≤ 50 vs. > 50 years) and menopausal status in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) tumors.

RESULTS

MammaPrint and BluePrint further classified 23% of tumors to a different subtype compared with immunohistochemistry, with more precise correspondence to pCR rates. Five-year DMFS and OS were highest in MammaPrint Low Risk, Luminal A-type and HER2-type tumors, and lowest in MammaPrint High Risk, Luminal B-type and Basal-type tumors. There was no significant difference in chemosensitivity between younger and older patients with Low-Risk (2.2% vs. 3.8%; p = 0.64) or High-Risk tumors (14.5% vs. 11.5%; p = 0.42), or within each BluePrint subtype; this was similar when stratifying by menopausal status. The 5-year outcomes were comparable by age or menopausal status for each molecular subtype.

CONCLUSION

Intrinsic preoperative chemosensitivity and long-term outcomes were precisely determined by BluePrint and MammaPrint regardless of patient age, supporting the utility of these assays to inform treatment and surgical decisions in early-stage breast cancer.

Integrating 31-Gene Expression Profiling With Clinicopathologic Features to Optimize Cutaneous Melanoma Sentinel Lymph Node Metastasis Prediction

National guidelines recommend sentinel lymph node biopsy (SLNB) be offered to patients with > 10% likelihood of sentinel lymph node (SLN) positivity. On the other hand, guidelines do not recommend SLNB for patients with T1a tumors without high-risk features who have < 5% likelihood of a positive SLN. However, the decision to perform SLNB is less certain for patients with higher-risk T1 melanomas in which a positive node is expected 5%-10% of the time. We hypothesized that integrating clinicopathologic features with the 31-gene expression profile (31-GEP) score using advanced artificial intelligence techniques would provide more precise SLN risk prediction.

Correction to: SentimagIC: A Non-inferiority Trial Comparing Superparamagnetic Iron Oxide Versus Technetium-99m and Blue Dye in the Detection of Axillary Sentinel Nodes in Patients with Early-Stage Breast Cancer

In the original article the authors' disclosures were incomplete.

Final analysis of relapse-free survival in a multicenter, double-blind, placebo-controlled trial of seviprotimut-L polyvalent melanoma vaccine after resection of high-risk melanoma

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Background: Seviprotimut-L is a vaccine prepared from antigens of 3 human melanoma cell lines, administered with alum. Prior formulations induced T cell and antibody responses and improved survival in a small phase II clinical trial. Part B1 of MAVIS (Melanoma Antigen Vaccine Immunotherapy Study, a three part, Phase III clinical program), was a multicenter, double-blind, placebo-controlled trial to assess efficacy of seviprotimut-L, with the primary endpoint of relapse-free survival (RFS). The goal of Part B1 was to guide design of the pivotal Part B2. Methods: Patients with AJCC v7 stage IIB-III cutaneous melanoma, after surgical resection, age 18-75, ECOG PS 0-1, were randomized 2:1 to seviprotimut-L 40 mcg or placebo, injected subcutaneously every 2 weeks x 5, then monthly x 4, then every 3 months x 9. Patients were stratified by stage (IIB/C, IIIA, IIIB/C). Target enrollment was 325. The study was powered for assessment of RFS, with target hazard ratio (HR) of 0.625, one-sided alpha of 0.10, and power 80%. Final data are presented. Results: 347 patients were randomized. Arms were well-balanced. Treatment-related adverse events (AEs) led to discontinuation in 0.4% and 0%, respectively, for vaccine and placebo arms. There were no treatment-related SAEs. By intent-to-treat (ITT) analysis, RFS was not significantly longer for seviprotimut-L in the full study population but trended toward benefit (HR 0.88). Subgroup analysis based on planned stratification revealed the hazard ratio (HR) for the Stage IIB/IIC subset (randomization stratum, n=111) to be 0.65 (95% CI [0.37, 1.17]), favoring seviprotimut-L. Age can decrease immune competence: RFS was longer with vaccine for patients age <60 overall (N = 191, HR = 0.64 [0.38, 1.08]) and among Stage IIB/C patients (N = 52, HR = 0.32 [0.12, 0.86]). The effect modification interaction p value for age for stage IIB/IIC patients was 0.056. In a multivariable RFS model, for IIB/IIC patients <60 with ulceration (n=38), HR = 0.209 [0.07,0.61]. For overall survival, for patients < 60, HR = 0.41 [0.33,1.14] (n=191, 19 deaths) and for those ≥60, HR = 0.92 [0.39,2.12] (n = 156, 24 deaths). Conclusions: Seviprotimut-L is very well-tolerated. Subgroup efficacy analyses identified populations who may benefit from Seviprotimut-L: those with Stage IIB/IIC melanoma and those under age 60. These data support design of the definitive part B2 of the MAVIS phase III trial to test seviprotimut-L for stage IIB/C patients, with stratification by age and ulceration. Clinical trial information: NCT01546571.

SentimagIC: A Non-inferiority Trial Comparing Superparamagnetic Iron Oxide Versus Technetium-99m and Blue Dye in the Detection of Axillary Sentinel Nodes in Patients with Early-Stage Breast Cancer

BACKGROUND

Sentinel lymph node biopsy (SLNB) is a highly accurate method for staging the axilla in early breast cancer. Superparamagnetic iron oxide mapping agents have been explored to overcome the disadvantages of the standard SLNB technique, which uses a radioisotope tracer with or without blue dye. One such agent, Sienna+, was shown to be non-inferior to the standard technique for SLNB in a number of studies. The SentimagIC trial was designed to establish the non-inferiority of a new formulation of this magnetic tracer, Magtrace (formerly SiennaXP).

METHODS

Patients with clinically node-negative early-stage breast cancer were recruited from six centers in the US. Patients received radioisotope and isosulfan blue dye injections, followed by an intraoperative injection of magnetic tracer, prior to SLNB. The sentinel node identification rate was compared between the magnetic and standard techniques to evaluate non-inferiority and concordance.

RESULTS

Data were collected for 146 procedures in 146 patients. The per patient detection rate was 99.3% (145/146) when using the magnetic tracer and 98.6% (144/146) when using the standard technique, while the nodal detection rate was 94.3% (348/369 nodes) when using the magnetic tracer and 93.5% (345/369) when using the standard technique (difference 0.8%, 95% binomial confidence interval lower bound - 2.1%). Of the 22 patients with positive sentinel lymph nodes (SLNs), 21 (95.4%) were detected by both the magnetic tracer and the standard technique. All malignant nodes detected by standard technique were also identified by the magnetic technique.

CONCLUSION

The magnetic technique is non-inferior to the standard technique of radioisotope and blue dye for axillary SLN detection in early-stage breast cancer. The magnetic technique is therefore a viable alternative.

Abstract CT220: Expansion into multiple institutions for training in the use of the LUM Imaging System for intraoperative detection of residual cancer in the tumor bed of female subjects with breast cancer

Background: Obtaining tumor-free margins is critical for local control in breast conserving surgery. Currently, 20-40% of lumpectomy patients have positive margins that require surgical re-excision; this is a significant burden for patients, surgeons and the healthcare system. Therefore, it is of paramount importance that all cancer be resected from the tumor bed during lumpectomy surgery. The LUM Imaging System consists of a fluorescence-based imaging agent, a hand-held wide-field detector (LUM Imaging Device) used to image the surgical cavity walls intraoperatively in real-time after the resection of the main lumpectomy specimen, and a proprietary tumor detection algorithm that highlights regions in the tumor bed suspected to contain residual cancer.

Methods: This multi-site clinical study is designed to refine the tumor detection algorithm developed in previous studies by correlating images generated by the LUM Imaging System with histopathology results. This is a prospective, interventional feasibility study and is an introductory arm to a pivotal study which will evaluate the safety and efficacy of the LUM Imaging System in reducing the positive margin rate during standard of care lumpectomies. Up to 250 adult female breast cancer patients undergoing lumpectomies are being enrolled at sixteen medical centers across the US. The novel imaging agent, LUM015, is injected into all enrolled subjects prior to their lumpectomy procedure. Subjects undergo the standard of care lumpectomy followed by intraoperative use of the LUM Imaging System which helps guide surgeons in identifying potential residual tumor tissue. The primary objective is to assess performance characteristics of the LUM Imaging System and to fine-tune the tumor detection algorithm. A secondary objective is to develop and refine the process of implementing the LUM Imaging System into institution-specific workflows during lumpectomies. A comprehensive process to evaluate the LUM Imaging System has been implemented and will be reported. This study is being conducted under an Investigational Device Exemption (IDE) approved by the FDA.

To date, 72 subjects have been imaged using the LUM Imaging System.

Successful implementation of standardized tissue collection, naming conventions, and LUM Imaging System training is intended to improve the quality and integrity of the data collected in the upcoming pivotal clinical trial to evaluate the safety and efficacy of the LUM Imaging System.

This study is partially funded by a grant from the National Cancer Institute (award 1R44CA211013) to support biomedical technology development and Lumicell Inc. and is registered on Clinical Trials.gov as NCT03321929.

Citation Format: Kate Smith, Jorge M. Ferrer, Barbara L. Smith, E. Shelley Hwang, Kelly K. Hunt, Daleela G. Dodge, Stephen E. Karp, Stephanie A. Valente, Irene L. Wapnir, Lynne P. Clark, David R. Carr, Peter D. Beitsch, Donna L. Dyess, Beth-Ann Lesnikoski, Peter W. Blumencranz, Nayana S. Dekhne, Linsey P. Gold, Anees Chagpar, Katherine Kacena, Livia Gjylameti, Felix Geissler. Expansion into multiple institutions for training in the use of the LUM Imaging System for intraoperative detection of residual cancer in the tumor bed of female subjects with breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT220.

Comprehensive germline multigene panel testing changes clinical care for patients with breast cancer: Untapped clinical utility and PARP inhibitor trial eligibility

1583

Background: HBOC testing guidelines were established to identify patients with clinically actionable variants and limit economic burden. We report the impact of germline results on health outcome based on clinical decision making and treatment interventions, regardless of guidelines, in a multi-center registry. Methods: 20 community-based and academic participated in an IRB approved registry. Patients with breast cancer were tested with an 80-gene panel; clinical information was collected. Results: Data on 912 patients has been analyzed to date. 50.5% met NCCN criteria; 49.5% did not. Pathogenic/likely pathogenic (P/LP) germline mutations were found in 8.65% of patients. Of all patients with P/LP findings, 85% had variants in cancer-risk genes with established management recommendations and 80% had germline variants conferring eligibility for clinical trials and precision medicine-based cancer treatments, such as PARP inhibitors. For 62% of patients with P/LP germline mutations, clinicians reported results impacted patients’ health outcome. And for 69%, results impacted the health outcome of patients’ relatives. There was no significant association between BRCAPRO scores and patients having a P/LP finding, whether in BRCA1/2 alone (p = 0.42) or for any cancer gene (p = 0.57). Physician reported impact on patient outcome associated significantly with the presence of P/LP germline findings (p < 0.00001). There was no significant difference in the clinician reported clinical utility of variants of uncertain significance (VUS) compared to negative results (p = 0.467). Conclusions: Comprehensive panel testing of breast cancer patients impacts physician assessed patient outcomes and informs changes in surgical treatment strategy, medical therapies and proactive screening. The data suggest that BRCAPRO calculators are poor predictors of germline presence of P/LP findings. Physicians in this study demonstrate the ability to discern the clinically actionable value of P/LP mutations from non-actionable VUS. Multigene panels impact breast cancer patient care by identifying precision medicine treatment interventions, and guiding long-term medical management and preventive surveillance for patients and family members.

Underdiagnosis of Hereditary Breast Cancer: Are Genetic Testing Guidelines a Tool or an Obstacle?

PURPOSE

An estimated 10% of breast and ovarian cancers result from hereditary causes. Current testing guidelines for germ line susceptibility genes in patients with breast carcinoma were developed to identify carriers of BRCA1/ 2 variants and have evolved in the panel-testing era. We evaluated the capability of the National Comprehensive Cancer Network (NCCN) guidelines to identify patients with breast cancer with pathogenic variants in expanded panel testing.

METHODS

An institutional review board-approved multicenter prospective registry was initiated with 20 community and academic sites experienced in cancer genetic testing and counseling. Eligibility criteria included patients with a previously or newly diagnosed breast cancer who had not undergone either single- or multigene testing. Consecutive patients 18 to 90 years of age were consented and underwent an 80-gene panel test. Health Insurance Portability and Accountability Act-compliant electronic case report forms collected information on patient demographics, diagnoses, phenotypes, and test results.

RESULTS

More than 1,000 patients were enrolled, and data records for 959 patients were analyzed; 49.95% met NCCN criteria, and 50.05% did not. Overall, 8.65% of patients had a pathogenic/likely pathogenic (P/LP) variant. Of patients who met NCCN guidelines with test results, 9.39% had a P/LP variant. Of patients who did not meet guidelines, 7.9% had a P/LP variant. The difference in positive results between these groups was not statistically significant (Fisher's exact test P = .4241).

CONCLUSION

Our results indicate that nearly half of patients with breast cancer with a P/LP variant with clinically actionable and/or management guidelines in development are missed by current testing guidelines. We recommend that all patients with a diagnosis of breast cancer undergo expanded panel testing.

BCT score predicts chemotherapy benefit in Asian patients with hormone receptor-positive, HER2-negative, lymph node-negative breast cancer

The Breast Cancer Test (BCT) score has been validated for its ability to predict the risk of distant metastasis in hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer. This study aimed to examine the value of the BCT score for predicting the benefit of adjuvant chemotherapy for Korean women with hormone receptor-positive, HER2-negative, lymph node-negative breast cancer. The study included 346 patients treated with either hormone therapy alone (n = 203) or hormone therapy plus chemotherapy (n = 143), and compared patient survival between the two treatment groups. The effect of BCT score on patient survival by treatment group was assessed using Cox proportional hazards models. Based on the results, the BCT score was prognostic for distant metastasis-free survival and breast cancer-specific survival in the hormone therapy alone group. There was no significant difference between the treatment groups in terms of 10-year distant metastasis-free survival in the overall patient population. However, when patients were classified as low risk (n = 266) and high risk (n = 80) according to the BCT score, addition of adjuvant chemotherapy to hormone therapy for patients classified as BCT high-risk group led to a significant improvement in 10-year distant metastasis-free survival, from 65.4% to 91.9% (hazard ratio, 0.18; 95% confidence interval, 0.05–0.64; P = 0.003); in contrast, there was no benefit for the BCT low-risk group. The stratification of patients according to the BCT score also identified clinically high-risk patients who may not benefit from chemotherapy. Results were similar for breast cancer-specific survival. In conclusion, the BCT score was not only of prognostic value but was also a predictor of chemotherapy benefit for Korean patients with hormone receptor-positive, HER2-negative, lymph node-negative breast cancer.

Effect of Axillary Dissection vs No Axillary Dissection on 10-Year Overall Survival Among Women With Invasive Breast Cancer and Sentinel Node Metastasis: The ACOSOG Z0011 (Alliance) Randomized Clinical Trial

IMPORTANCE

The results of the American College of Surgeons Oncology Group Z0011 (ACOSOG Z0011) trial were first reported in 2005 with a median follow-up of 6.3 years. Longer follow-up was necessary because the majority of the patients had estrogen receptor-positive tumors that may recur later in the disease course (the ACOSOG is now part of the Alliance for Clinical Trials in Oncology).

OBJECTIVE

To determine whether the 10-year overall survival of patients with sentinel lymph node metastases treated with breast-conserving therapy and sentinel lymph node dissection (SLND) alone without axillary lymph node dissection (ALND) is noninferior to that of women treated with axillary dissection.

DESIGN, SETTING, AND PARTICIPANTS

The ACOSOG Z0011 phase 3 randomized clinical trial enrolled patients from May 1999 to December 2004 at 115 sites (both academic and community medical centers). The last date of follow-up was September 29, 2015, in the ACOSOG Z0011 (Alliance) trial. Eligible patients were women with clinical T1 or T2 invasive breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases.

INTERVENTIONS

All patients had planned lumpectomy, planned tangential whole-breast irradiation, and adjuvant systemic therapy. Third-field radiation was prohibited.

MAIN OUTCOMES AND MEASURES

The primary outcome was overall survival with a noninferiority hazard ratio (HR) margin of 1.3. The secondary outcome was disease-free survival.

RESULTS

Among 891 women who were randomized (median age, 55 years), 856 (96%) completed the trial (446 in the SLND alone group and 445 in the ALND group). At a median follow-up of 9.3 years (interquartile range, 6.93-10.34 years), the 10-year overall survival was 86.3% in the SLND alone group and 83.6% in the ALND group (HR, 0.85 [1-sided 95% CI, 0-1.16]; noninferiority P = .02). The 10-year disease-free survival was 80.2% in the SLND alone group and 78.2% in the ALND group (HR, 0.85 [95% CI, 0.62-1.17]; P = .32). Between year 5 and year 10, 1 regional recurrence was seen in the SLND alone group vs none in the ALND group. Ten-year regional recurrence did not differ significantly between the 2 groups.

CONCLUSIONS AND RELEVANCE

Among women with T1 or T2 invasive primary breast cancer, no palpable axillary adenopathy, and 1 or 2 sentinel lymph nodes containing metastases, 10-year overall survival for patients treated with sentinel lymph node dissection alone was noninferior to overall survival for those treated with axillary lymph node dissection. These findings do not support routine use of axillary lymph node dissection in this patient population based on 10-year outcomes.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00003855.

Completion Dissection or Observation for Sentinel-Node Metastasis in Melanoma

BACKGROUND

Sentinel-lymph-node biopsy is associated with increased melanoma-specific survival (i.e., survival until death from melanoma) among patients with node-positive intermediate-thickness melanomas (1.2 to 3.5 mm). The value of completion lymph-node dissection for patients with sentinel-node metastases is not clear.

METHODS

In an international trial, we randomly assigned patients with sentinel-node metastases detected by means of standard pathological assessment or a multimarker molecular assay to immediate completion lymph-node dissection (dissection group) or nodal observation with ultrasonography (observation group). The primary end point was melanoma-specific survival. Secondary end points included disease-free survival and the cumulative rate of nonsentinel-node metastasis.

RESULTS

Immediate completion lymph-node dissection was not associated with increased melanoma-specific survival among 1934 patients with data that could be evaluated in an intention-to-treat analysis or among 1755 patients in the per-protocol analysis. In the per-protocol analysis, the mean (±SE) 3-year rate of melanoma-specific survival was similar in the dissection group and the observation group (86±1.3% and 86±1.2%, respectively; P=0.42 by the log-rank test) at a median follow-up of 43 months. The rate of disease-free survival was slightly higher in the dissection group than in the observation group (68±1.7% and 63±1.7%, respectively; P=0.05 by the log-rank test) at 3 years, based on an increased rate of disease control in the regional nodes at 3 years (92±1.0% vs. 77±1.5%; P<0.001 by the log-rank test); these results must be interpreted with caution. Nonsentinel-node metastases, identified in 11.5% of the patients in the dissection group, were a strong, independent prognostic factor for recurrence (hazard ratio, 1.78; P=0.005). Lymphedema was observed in 24.1% of the patients in the dissection group and in 6.3% of those in the observation group.

CONCLUSIONS

Immediate completion lymph-node dissection increased the rate of regional disease control and provided prognostic information but did not increase melanoma-specific survival among patients with melanoma and sentinel-node metastases. (Funded by the National Cancer Institute and others; MSLT-II ClinicalTrials.gov number, NCT00297895 .).

Final Results of the Sunbelt Melanoma Trial: A Multi-Institutional Prospective Randomized Phase III Study Evaluating the Role of Adjuvant High-Dose Interferon Alfa-2b and Completion Lymph Node Dissection for Patients Staged by Sentinel Lymph Node Biopsy

PURPOSE

The Sunbelt Melanoma Trial is a prospective randomized trial evaluating the role of high-dose interferon alfa-2b therapy (HDI) or completion lymph node dissection (CLND) for patients with melanoma staged by sentinel lymph node (SLN) biopsy.

PATIENTS AND METHODS

Patients were eligible if they were age 18 to 70 years with primary cutaneous melanoma ≥ 1.0 mm Breslow thickness and underwent SLN biopsy. In Protocol A, patients with a single tumor-positive lymph node after SLN biopsy underwent CLND and were randomly assigned to observation versus HDI. In Protocol B, patients with tumor-negative SLN by standard histopathology and immunohistochemistry underwent molecular staging by reverse transcriptase polymerase chain reaction (RT-PCR). Patients positive by RT-PCR were randomly assigned to observation versus CLND versus CLND+HDI. Primary end points were disease-free survival (DFS) and overall survival (OS).

RESULTS

In the Protocol A intention-to-treat analysis, there were no significant differences in DFS (hazard ratio, 0.82; P = .45) or OS (hazard ratio, 1.10; P = .68) for patients randomly assigned to HDI versus observation. In the Protocol B intention-to-treat analysis, there were no significant differences in overall DFS (P = .069) or OS (P = .77) across the three randomized treatment arms. Similarly, efficacy analysis (excluding patients who did not receive the assigned treatment) did not demonstrate significant differences in DFS or OS in Protocol A or Protocol B. Median follow-up time was 71 months.

CONCLUSION

No survival benefit for adjuvant HDI in patients with a single positive SLN was found. Among patients with tumor-negative SLN by conventional pathology but with melanoma detected in the SLN by RT-PCR, there was no OS benefit for CLND or CLND+HDI.

Abstract OT2-02-03: Magnetic nano-device for identification of the breast sentinel nodes – A novel method

Breast sentinel node biopsy (SNB) is a well-established procedure that has supplanted traditional axillary dissection for most clinically node-negative breast cancer patients. Techniques to identify the draining lymph nodes include colored dyes and radioactive compounds. The Sentimag system uses a non-radioactive magnetic tracer and a handheld magnetic probe to identify sentinel nodes (SNs). The Sentimag Intraoperative Comparison (SentimagIC) study compares the magnetic technique with the standard combination of radioisotope and isosulfan blue dye.

Methods: SiennaXP is a nano device composed of coated iron oxide nanoparticles designed to optimize lymphatic uptake and SN retention. The Sentimag breast SNB technique involves injection of 2cc of SiennaXP fluid into Sappey's subareolar plexus followed by 5 minutes of breast massage and an additional 15 minutes of time to optimize drainage prior to beginning the procedure. The Sentimag hand held probe is then used to identify a magnetic 'hotspot' through the skin of the axilla. The usual transverse axillary incision is made and the magnetometer is used to identify the SNs. The SentimagIC study involves utilizing the Sentimag technique in combination with the 'standard' techniques of isosulfan blue dye and 99technetium sulfur colloid. All blue, radioactive and magnetic SNs are removed and identified as stained blue (from isosulfan blue dye) or black/brown (from SiennaXP) or not, and both radioactive and magnetic counts are taken ex vivo on each node. Currently there are 6 active sites with a total of 60 patients enrolled.

Trial design: This is a pivotal, prospective, open label, multicenter, paired comparison of the magnetic technique with the standard of care for lymph node localization in patients with breast cancer.

Primary endpoints: The lymph node detection rate with SentiMag / SiennaXP and the detection rate with the standard of care; and the safety of Sentimag / SiennaXP as indicated by adverse events.

Eligibility: Diagnosis of primary breast cancer or pure ductal carcinoma in situ (DCIS); Scheduled for sentinel lymph node biopsy; Clinical negative node status (i.e. T0-3, N0, M0).

Statistical methods: The primary hypothesis is that the magnetic technique is non-inferior to the standard technique. Based on an expected detection rate of 95% for both techniques and a non-inferiority margin of 5%, 140 subjects will be required to show non-inferiority with 85% power.

Discussion: SNB for breast cancer is a robust procedure, able to identify the draining lymph nodes of the breast in essentially all patients. Many techniques have been used including radioactive tracers (utilized on most cases) and colored dyes. SentiMag utilizes a unique nano device that can identify the same draining nodes but without the radioactivity used in most procedures. Radioactive dyes must be handled carefully to minimize radiation exposure to healthcare providers and the patient from the manufacturing process, delivery to facility, injection under a nuclear physician license, and the surgical procedure. This novel technique may supplant radioactive tracers allowing SNs to be removed without the patient/healthcare providers being exposed to radiation or the scheduling inconvenience of pre-procedure injection.

Citation Format: Beitsch PD, Hunt KK, Bold RJ, Gittleman MA, Blair SL, Alvarado MD, Harmer QJ. Magnetic nano-device for identification of the breast sentinel nodes – A novel method. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-02-03.

Breast surgeons' attitudes towards bilateral risk-reducing mastectomy: A National Survey of American Surgeons

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Background: Bilateral risk-reducing mastectomy (BRRM) confers the greatest risk-reduction in women at high-risk of developing breast cancer. Uptake of BRRM is influenced by the attitudes of these women as well as the breast surgeons offering these procedures. We surveyed surgeon members of the American Society of Breast Surgeons to assess their attitudes and knowledge. Methods: An International Cancer Risk Communication Study (InCRisC) questionnaire, previously used to assess attitudes of European physicians and surgeons was sent to 2648 members. Personal and occupational characteristics were recorded and knowledge of cancer genetics and attitudes to BRRM were assessed using clinical vignettes. Results: 439 breast surgeons responded. 98% of surgeons actively took a family history of the father. Almost 100% of surgeons reported a positive attitude towards BRRM. Female surgeons and those treating greater than 100 breast cancers a year were predictors of knowledge of breast cancer genetics and a positive attitude towards BRRM. Conclusions: Multiple factors contribute to surgeons' attitudes towards BRRM. Gender of surgeon and workload contribute to theses observed variations.

Functional subtyping with BluePrint 80-gene profile to identify distinct triple-positive subtypes with and without trastuzumab/chemosensitivity

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Background: Classification by molecular subtype can aid in the selection of therapy for patients with breast cancer. However at present, the methodology for molecular subtyping is not standardized. The aim of the prospective NBRST study is to compare chemosensitivity as defined by pathological Complete Response (pCR) using the 80-gene BluePrint (BP) functional subtype profile vs. conventional IHC/FISH subtyping. Methods: The study includes women aged 18–90 with histologically proven breast cancer, written informed consent, no excision biopsy or axillary dissection, and no prior therapy for breast cancer. Neo-adjuvant Chemotherapy (NCT) was at the discretion of the physician adhering to NCCN approved or other peer-reviewed regimens. BP in combination with MammaPrint classifies patients into 4 molecular subgroups: Luminal A, Luminal B, HER2 and Basal. Results: 721 patients had definitive surgery. 58/335 (17%) IHC/FISH HR+/HER2- patients were re-classified by BP as Basal (57) or HER2 (1). 92/222 (41%) IHC/FISH HER2+ patients were re-classified as BP Luminal (67) or BP Basal (25). 7/164 (4%) IHC/FISH triple negative (TN) patients were re-classified as BP Luminal (5) or BP HER2 (2). NCT pCR rates were 3% in Luminal A and 9% in Luminal B patients versus 10% pCR in IHC/FISH luminal patients. The NCT pCR rate was 54% in BP HER2 patients. This is significantly superior (p = 0.02) to the pCR rate in IHC/FISH HER2+ patients (40%). BP Basal and IHC/FISH TN had a pCR rate of 35%. Functional BP subtyping divided the 137 IHC/FISH triple positive patients into two major subgroups: BP Luminal (n = 66, pCR = 11%) and BP HER2 (n = 60, pCR = 45%).11 patients were re-classified as BP Basal with pCR = 45%. Conclusions: Molecular subtyping using BP leads to a reclassification of 23% of tumors. The re-classification is most prominent in classically assessed triple positive patients where 48% of patients are re-assigned to the less responsive BP Luminal-type group vs. 44% of patients assigned to the responsive BP HER2-type group. These findings confirm the more accurate identification of molecular subgroups for treatment decision by BluePrint functional subtype classifier. Clinical trial information: NCT01479101.

Nomogram for predicting the risk of locoregional recurrence in patients treated with accelerated partial-breast irradiation

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Background: There are limited tools to guide clinicians regarding the risk of locoregional recurrence (LRR) in patients wishing to pursue APBI. The purpose of this study was to develop a nomogram taking into account clinicopathologic features to predict LRR in patients treated with APBI for early stage breast cancer. Methods: A total of 2,000 breasts (1,990 women) were treated with APBI at William Beaumont Hospital (N=551) or on the ASBrS MammoSite Registry Trial (N=1,449). Techniques included multiplanar interstitial catheters (N=98), balloon-based brachytherapy (N=1,689), and 3D conformal radiotherapy (N=213). Clinicopathologic variables were gathered prospectively. A nomogram was formulated utilizing the Cox Proportional Hazards Regression model to predict for LRR. This was validated by generating a bias-corrected index and cross-validated with a C-index. Results: Median follow-up was 5.5 years (0.9 to 18.3). Of the 2,000 cases, 435 were excluded due to missing data. Univariate analysis found that age <50, pre/perimenopausal status, close/positive margins, ER negativity, and high grade were associated with a higher frequency of LRR. These five independent covariates were used to create adjusted estimates, weighting each on a scale of 0 to 100. The total score is identified on a points scale to obtain the probability of an LRR over the study period. The model demonstrated good concordance for predicting LRR with a C-index of 0.641. Conclusions: The formulation of a practical, easy-to-use nomogram for calculating the risk of LRR in patients undergoing APBI will help guide the appropriate selection of patients for off-protocol utilization of APBI.

Chemosensitivity and endocrine sensitivity prediction by MammaPrint and BluePrint in the Neoadjuvant Breast Registry Symphony Trial (NBRST)

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Background: Classification into molecular subtypes is important for the selection of therapy for patients with breast cancer. Previous analyses demonstrated that breast cancer subtypes have distinct clinical outcome (Gluck, BCRT 2013). The aim of the prospective NBRST study is to measure chemosensitivity as defined by pathologic complete response (pCR), or endocrine sensitivity as defined by partial response (PR) and metastasis-free survival in molecular subgroups. Methods: The study includes women aged 18 to 90 with histologically proven breast cancer, who are scheduled to start neoadjuvant chemotherapy (NCT) or neoadjuvant endocrine therapy (NET), and who provide written informed consent. Additional inclusion criteria include no excision biopsy or axillary dissection, no confirmed distant metastatic disease, and no prior therapy for breast cancer. Treatment is at the discretion of the physician adhering to NCCN approved regimens. Results: Of 336 patients, T1-4 N0-3, had definitive surgery and the overall pCR rate was 24%. 32/167 (19%) IHC/FISH ERPR+/Her2- patients were reclassified by BluePrint (31 Basal). 43/95 (45%) IHC/FISH Her2+ patients were reclassified by BluePrint (25 Luminal and 18 Basal). 3/74 (3%) IHC/FISH triple-negative patients were not Basal by BluePrint. Of 45 (13%) patients classified as Luminal A 32 received NCT; one patient (3%) had a pCR; 13 patients received NET and 9 (70%) had a PR. Of 116 (35%) patients classified as Luminal B, 111 received NCT and seven (6%) had a pCR. The pCR rate (17/149 (11%)) in IHC/FISH ERPR+/HER2- patients was higher. Fifty-five (16%) are BluePrint HER2 and received NCT (51 plus trastuzumab); 27 (49%) had a pCR compared to 35/95 (37%) in IHC/FISH HER2+ patients. One-hundred twenty (36%) are BluePrint Basal and received NCT; 46 (38%) had a pCR, similar to the pCR percentage seen in the 74 patients designated triple-negative by IHC/FISH. Conclusions: Molecular subtyping using MammaPrint and BluePrint leads to a reclassification of 23% (78/336) of tumors. BluePrint reclassification resulted in better grouping of patients into expected response groups compared to local surrogate subtyping with immunostains.

Chemosensitivity predicted by BluePrint 80-gene functional subtype and MammaPrint in the Prospective Neoadjuvant Breast Registry Symphony Trial (NBRST)

Purpose

The purpose of the NBRST study is to compare a multigene classifier to conventional immunohistochemistry (IHC)/fluorescence in situ hybridization (FISH) subtyping to predict chemosensitivity as defined by pathological complete response (pCR) or endocrine sensitivity as defined by partial response.

Methods

The study includes women with histologically proven breast cancer, who will receive neoadjuvant chemotherapy (NCT) or neoadjuvant endocrine therapy. BluePrint in combination with MammaPrint classifies patients into four molecular subgroups: Luminal A, Luminal B, HER2, and Basal.

Results

A total of 426 patients had definitive surgery. Thirty-seven of 211 (18 %) IHC/FISH hormone receptor (HR)+/HER2− patients were reclassified by Blueprint as Basal (n = 35) or HER2 (n = 2). Fifty-three of 123 (43 %) IHC/FISH HER2+ patients were reclassified as Luminal (n = 36) or Basal (n = 17). Four of 92 (4 %) IHC/FISH triple-negative (TN) patients were reclassified as Luminal (n = 2) or HER2 (n = 2). NCT pCR rates were 2 % in Luminal A and 7 % Luminal B patients versus 10 % pCR in IHC/FISH HR+/HER2− patients. The NCT pCR rate was 53 % in BluePrint HER2 patients. This is significantly superior (p = 0.047) to the pCR rate in IHC/FISH HER2+ patients (38 %). The pCR rate of 36 of 75 IHC/FISH HER2+/HR+ patients reclassified as BPLuminal is 3 %. NCT pCR for BluePrint Basal patients was 49 of 140 (35 %), comparable to the 34 of 92 pCR rate (37 %) in IHC/FISH TN patients.

Conclusions

BluePrint molecular subtyping reclassifies 22 % (94/426) of tumors, reassigning more responsive patients to the HER2 and Basal categories while reassigning less responsive patients to the Luminal category. These findings suggest that compared with IHC/FISH, BluePrint more accurately identifies patients likely to respond (or not respond) to NCT.

Abstract P2-18-07: Nipple sparing mastectomy-infectious complication risk. A preliminary assessment of the American Society of Breast Surgeons nipple sparing mastectomy registry

Objectives: The American Society of Breast Surgeons (ASBS) Nipple Sparing Mastectomy Registry (NSMR) is a prospective, IRB approved, non-randomized, multi-institutional registry assessing surgical techniques, utilized metrics, oncologic outcome, and aesthetic outcome of nipple sparing mastectomies. The registry has been open for enrollment for 26 months. The target accrual is 1000 individuals. This abstract specifically analyzes rates of post-operative infection in NSMs.

Methods: Fifty two investigators from 41 institutions are participating in the ASBS NSMR. A total of 373 patients underwent 631 mastectomies, with indications of prophylaxis (365), cancer (248), and unknown (18). We assessed a sub group of 449 mastectomies, with indications of prophylaxis (253) and cancer (196) that had all data sets completed. We assessed infection rates(characterized as needing oral or iv antibiotics with or without removal of implant/expander and/or debridement) in the entire group as well as by indication (cancer vs. prophylaxis). Factors such as smoking history, previous radiation therapy, previous surgery, incision type, reconstruction technique, and flap dissection technique were analyzed.

Results: In a subgroup of 449 mastectomies (253 prophylactic and 196 cancer):

Post operative infections were reported in 22 (4.9%) of patients: 7 (3.6%) of mastectomies with an indication of cancer and 15 (5.9%) of prophylactic mastectomies (p-value 0.3140). Infections were characterized as: treatment with oral antibiotics alone, treatment with i.v. antibiotics alone, iv antibiotics with washout or debridement, or antibiotics and implant/ tissue expander removal. No correlation was found in smoking history (p-value 1.000), previous breast surgery (p-value 0.1277) or previous radiation (p-value 0.6024). No correlation was found in incision utilized, reconstruction technique, or method of flap dissection either.

Conclusion:

The rate of postoperative infections in nipple sparing mastectomies is comparable if not lower than non-nipple sparing mastectomies. No statistically significant difference in infection rate was found between mastectomies completed for prophylaxis or cancer. No correlation was found between factors such as smoking history, history of radiation therapy, prior breast surgery, incision utilized, reconstruction technique, or method of flap dissection. Improved aesthetics with a nipple sparing approach (technically more demanding and typically through a smaller incision) does not come at the cost of a higher rate of infectious complications.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-18-07.

The use of bioimpedance spectroscopy to monitor response to treatment interventions with breast cancer-related lymphedema

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Background: Currently, limited tools are available to assess response to therapy in patients with breast cancer related lymphedema (BCRL). The purpose of this study was to perform an exploratory analysis to determine if, in clinical settings, bioimpedance spectroscopy (BIS) can detect changes in extracellular fluid volume in response to treatment of BCRL. Methods: Three centers that had experience with BIS (L-Dex U400, ImpediMed Limited, Brisbane, Australia) provided retrospective data on 50 patients with breast cancer who were evaluated with BIS at baseline and following loco-regional procedures. Patients had a pre-surgical L-Dex measurement as well as at least 2 post-surgical measurements (before and after BCRL intervention). Decisions regarding intervention were made by physicians with no L-Dex score cut-off utilized. An analysis was performed comparing changes in L-Dex scores for those patients undergoing treatment for BCRL (n=13) versus those not undergoing intervention (n=37). A second analysis was also performed on all patients with elevated L-Dex scores compared to baseline prior to intervention (n=32). Results: The mean age was 54 years old. Fifty four percent of patients underwent SLN biopsy with a mean of 7.9 nodes removed. The mean change in L-Dex score from baseline (pre-treatment) to the first post-surgical L-Dex score measurement was 3.3 +/- 6.8. When comparing the cohort treated for BCRL to those not treated, L-Dex scores were significantly reduced (-4.3 v. 0.1, p=0.005) following intervention. For the subset of patients with elevated L-Dex scores post-surgery, the change in L-Dex score following BCRL intervention was significantly reduced (-5.8 v. 0.1, p=0.001) compared with those observed. Conclusions: These results confirm that BIS can detect increases in L-Dex scores following breast surgery and can also detect reductions in L-Dex scores following intervention for early onset lymphedema. These results demonstrate that BIS has significant clinical utility as it can be used to monitor patients with early BCRL who undergo intervention and to follow these patients (through serial measurements) to document their short and long-term response to these treatments.

First results of the prospective Neoadjuvant Breast Registry Symphony Trial (NBRST)

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Background: Classification into molecular subtypes may be important for the selection of therapy for patients with early breast cancer. Previous analyses had shown that breast cancer subtypes have distinct clinical outcome (Sorlie, PNAS 2001; Esserman, BCRT 2011). The aim of the prospective NBRST study is to measure chemosensitivity as defined by pathological Complete Response (pCR), or endocrine sensitivity as defined by partial response (PR) and metastasis-free survival in molecular subgroups. Methods: The study includes women aged 18–90 with histologically proven breast cancer, who are scheduled to start neo-adjuvant chemotherapy (CT) or neo-adjuvant endocrine therapy (ET), and who provide written informed consent. Additional inclusion criteria include no excision biopsy or axillary dissection, no confirmed distant metastatic disease, and no prior therapy for breast cancer. Treatment is at the discretion of the physician adhering to NCCN approved regimens. 500 Patients will be enrolled. Results: 128 Patients (median age 52, range 22-79), T1-4 N0-3, had definitive surgery and the overall pCR rate was 22%.14 (11%) patients are classified as Luminal A-type (BluePrint Luminal/MammaPrint Low Risk) of whom 11 received neo-adjuvant CT; none of these patients had a pCR. While 3 patients received neo-adjuvant ET and all 3 had a PR. 47 (37%) Patients are classified as Luminal B-type (BluePrint Luminal/MammaPrint High Risk). All but 1 patient received neo-adjuvant CT and 4 (9%) had a pCR. 20 (16%) Patients are classified as BluePrint HER2-type and received neo-adjuvant CT plus Trastuzumab; 8 (40%) had a pCR. 47 (37%) Patients are classified as BluePrint Basal-type and received neo-adjuvant CT; 15 (32%) had a pCR. Of the patients with IHC/FISH HER2+ cancer 13/39 (33%) had a pCR and 6/21 (29%) of the patients with IHC/FISH triple negative breast cancer. Conclusions: We observed differences in pCR to neo-adjuvant treatment in groups stratified by BluePrint and MammaPrint. Patients with Luminal A-type breast cancer have a high response to neo-adjuvant endocrine therapy (100% PR) and no pCR to neo-adjuvant CT. While patients with BluePrint HER2-type and Basal-type breast cancer have a high pCR rate to neo-adjuvant CT. Clinical trial information: NCT01479101.

Evaluation of current consensus statement recommendations for accelerated partial breast irradiation: a pooled analysis of William Beaumont Hospital and American Society of Breast Surgeon MammoSite Registry Trial Data

PURPOSE

To determine whether the American Society for Radiation Oncology (ASTRO) Consensus Statement (CS) recommendations for accelerated partial breast irradiation (APBI) are associated with significantly different outcomes in a pooled analysis from William Beaumont Hospital (WBH) and the American Society of Breast Surgeons (ASBrS) MammoSite® Registry Trial.

METHODS AND MATERIALS

APBI was used to treat 2127 cases of early-stage breast cancer (WBH, n=678; ASBrS, n=1449). Three forms of APBI were used at WBH (interstitial, n=221; balloon-based, n=255; or 3-dimensional conformal radiation therapy, n=206), whereas all Registry Trial patients received balloon-based brachytherapy. Patients were divided according to the ASTRO CS into suitable (n=661, 36.5%), cautionary (n=850, 46.9%), and unsuitable (n=302, 16.7%) categories. Tumor characteristics and clinical outcomes were analyzed according to CS group.

RESULTS

The median age was 65 years (range, 32-94 years), and the median tumor size was 10.0 mm (range, 0-45 mm). The median follow-up time was 60.6 months. The WBH cohort had more node-positive disease (6.9% vs 2.6%, P<.01) and cautionary patients (49.5% vs 41.8%, P=.06). The 5-year actuarial ipsilateral breast tumor recurrence (IBTR), regional nodal failure (RNF), and distant metastasis (DM) for the whole cohort were 2.8%, 0.6%, 1.6%. The rate of IBTR was not statistically higher between suitable (2.5%), cautionary (3.3%), or unsuitable (4.6%) patients (P=.20). The nonsignificant increase in IBTR for the cautionary and unsuitable categories was due to increased elsewhere failures and new primaries (P=.04), not tumor bed recurrence (P=.93).

CONCLUSIONS

Excellent outcomes after breast-conserving surgery and APBI were seen in our pooled analysis. The current ASTRO CS guidelines did not adequately differentiate patients at an increased risk of IBTR or tumor bed failure in this large patient cohort.

Evaluation of current consensus panel guidelines for APBI: A pooled analysis of William Beaumont Hospital and American Society of Breast Surgeons MammoSite registry trial data

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Background: To determine whether the ASTRO Consensus Panel (CP) guidelines for accelerated partial breast irradiation (APBI) are associated with significantly different outcomes in a pooled analysis from William Beaumont Hospital (WBH) and the American Society of Breast Surgeons (ASBrS) MammoSite Registry Trial. Methods: 2,127 cases of early-stage breast cancer were treated using APBI (WBH: n=678; ASBrS: n=1,449). Three forms of APBI were used at WBH (interstitial, n=221; balloon-based, n=255; or 3D-CRT, n=206) while all Registry Trial patients received balloon-based brachytherapy. Patients with complete coding necessary for ASTRO CP assignment (n=1,813) were divided into suitable (n=661, 36.5%), cautionary (n=850, 46.9%), and unsuitable (n=302, 16.7%) categories. Tumor characteristics and clinical outcomes were analyzed according to CP group. Results: Median age was 65 years (32-94 years) and median tumor size was 10.0mm (0-45mm). The WBH cohort had more node-positive disease (6.9% vs. 2.6%, p<0.01) and cautionary patients (49.5% vs. 41.8%, p=0.06). Five-year rates of ipsilateral breast tumor recurrence (IBTR), regional nodal failure (RNF), and distant metastasis (DM) for the whole cohort were 2.8%, 0.6%, 1.6%, respectively. When analyzed by CP group, the rate of IBTR was not statistically higher for suitable (2.5%), cautionary (3.3%), or unsuitable (4.6%) patients (p=0.20). The non-significant increase in IBTR for grouped cautionary/unsuitable categories was due to increased elsewhere failures/new primaries (p=0.04), not true recurrences (1.1-1.2%, all groups, p=0.94). A higher rate of DM was observed within the cautionary and unsuitable groups (3.3-3.6% vs. 0.7% for suitable, p=0.01), although cause-specific survival was the same for all patient categories (98.0-98.6%, all groups, p=0.47). Conclusions: Excellent outcomes following breast conserving surgery and APBI were seen in our pooled analysis. The current ASTRO CP guidelines did not adequately differentiate patients at an increased risk of IBTR or tumor bed failure within the largest patient population of cases treated with APBI to date.

Factors associated with optimal long-term cosmetic results in patients treated with accelerated partial breast irradiation using balloon-based brachytherapy

PURPOSE

To evaluate factors associated with optimal cosmetic results at 72 months for early-stage breast cancer patients treated with Mammosite balloon-based accelerated partial breast irradiation (APBI).

METHODS AND MATERIALS

A total of 1,440 patients (1,449 cases) with early-stage breast cancer undergoing breast-conserving therapy were treated with balloon-based brachytherapy to deliver APBI (34 Gy in 3.4-Gy fractions). Cosmetic outcome was evaluated at each follow-up visit and dichotomized as excellent/good (E/G) or fair/poor (F/P). Follow-up was evaluated at 36 and 72 months to establish long-term cosmesis, stability of cosmesis, and factors associated with optimal results.

RESULTS

The percentage of evaluable patients with excellent/good (E/G) cosmetic results at 36 months and more than 72 months were 93.3% (n = 708/759) and 90.4% (n = 235/260). Factors associated with optimal cosmetic results at 72 months included: larger skin spacing (p = 0.04) and T1 tumors (p = 0.02). Using multiple regression analysis, the only factors predictive of worse cosmetic outcome at 72 months were smaller skin spacing (odds ratio [OR], 0.89; confidence interval [CI], 0.80-0.99) and tumors greater than 2 cm (OR, 4.96, CI, 1.53-16.07). In all, 227 patients had both a 36-month and a 72-month cosmetic evaluation. The number of patients with E/G cosmetic results decreased only slightly from 93.4% at 3 years to 90.8% (p = 0.13) at 6 years, respectively.

CONCLUSIONS

APBI delivered with balloon-based brachytherapy produced E/G cosmetic results in 90.4% of cases at 6 years. Larger tumors (T2) and smaller skin spacing were found to be the two most important independent predictors of cosmesis.

Accelerated partial breast irradiation

Whole breast irradiation (WBI) is the standard after breast conservation surgery. However, WBI in selected patients has been questioned. Accelerated partial breast irradiation (APBI) focuses treatment on the lumpectomy bed. Many modalities of delivering APBI have been developed: multicatheter interstitial brachytherapy, MammoSite balloon catheter, single insertion multicatheter devices, three-dimensional conformal external-beam radiation therapy and intraoperative techniques. Numerous studies of APBI have demonstrated excellent local control and cosmetic outcomes in early-stage breast cancer patients.

Axillary dissection vs no axillary dissection in women with invasive breast cancer and sentinel node metastasis: a randomized clinical trial

CONTEXT

Sentinel lymph node dissection (SLND) accurately identifies nodal metastasis of early breast cancer, but it is not clear whether further nodal dissection affects survival.

OBJECTIVE

To determine the effects of complete axillary lymph node dissection (ALND) on survival of patients with sentinel lymph node (SLN) metastasis of breast cancer.

DESIGN, SETTING, AND PATIENTS

The American College of Surgeons Oncology Group Z0011 trial, a phase 3 noninferiority trial conducted at 115 sites and enrolling patients from May 1999 to December 2004. Patients were women with clinical T1-T2 invasive breast cancer, no palpable adenopathy, and 1 to 2 SLNs containing metastases identified by frozen section, touch preparation, or hematoxylin-eosin staining on permanent section. Targeted enrollment was 1900 women with final analysis after 500 deaths, but the trial closed early because mortality rate was lower than expected.

INTERVENTIONS

All patients underwent lumpectomy and tangential whole-breast irradiation. Those with SLN metastases identified by SLND were randomized to undergo ALND or no further axillary treatment. Those randomized to ALND underwent dissection of 10 or more nodes. Systemic therapy was at the discretion of the treating physician.

MAIN OUTCOME MEASURES

Overall survival was the primary end point, with a noninferiority margin of a 1-sided hazard ratio of less than 1.3 indicating that SLND alone is noninferior to ALND. Disease-free survival was a secondary end point.

RESULTS

Clinical and tumor characteristics were similar between 445 patients randomized to ALND and 446 randomized to SLND alone. However, the median number of nodes removed was 17 with ALND and 2 with SLND alone. At a median follow-up of 6.3 years (last follow-up, March 4, 2010), 5-year overall survival was 91.8% (95% confidence interval [CI], 89.1%-94.5%) with ALND and 92.5% (95% CI, 90.0%-95.1%) with SLND alone; 5-year disease-free survival was 82.2% (95% CI, 78.3%-86.3%) with ALND and 83.9% (95% CI, 80.2%-87.9%) with SLND alone. The hazard ratio for treatment-related overall survival was 0.79 (90% CI, 0.56-1.11) without adjustment and 0.87 (90% CI, 0.62-1.23) after adjusting for age and adjuvant therapy.

CONCLUSION

Among patients with limited SLN metastatic breast cancer treated with breast conservation and systemic therapy, the use of SLND alone compared with ALND did not result in inferior survival.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00003855.

A novel automated assay for the rapid identification of metastatic breast carcinoma in sentinel lymph nodes

BACKGROUND

The authors prospectively evaluated the performance of a proprietary molecular testing platform using one-step nucleic acid amplification (OSNA) for the detection of metastatic carcinoma in sentinel lymph nodes (SLNs) in a large multicenter trial and compared the OSNA results with the results from a detailed postoperative histopathologic evaluation (reference pathology) and from intraoperative imprint cytology (IC).

METHODS

In total, 1044 SLN samples from 496 patients at 11 clinical sites were analyzed. Alternate 1-mm sections were subjected to either detailed histopathologic evaluation with hematoxylin and eosin and pancytokeratin immunostaining or the OSNA Breast Cancer System, which was calibrated to detect tumor deposits >0.2 mm by measuring cytokeratin 19 messenger RNA. At 7 sites, IC was performed before permanent section. The OSNA results were classified as negative (<250 copies/μL), micrometastases (from ≥250 to <5000 copies/μL), or macrometastases (≥5000 copies/μL).

RESULTS

The sensitivity and specificity of the OSNA breast cancer system compared with reference pathology were 77.5% (95% confidence interval, 69.7%-84.2%) and 95.8% (95% confidence interval, 94.3%-97.0%), respectively, before discordant case analyses (DCA). Sensitivity and specificity after DCA were 82.7% and 97.7%, and final concordance was 95.8%. Performance for invasive lobular carcinoma demonstrated 88.2% sensitivity (95% confidence interval, 63.6%-98.5%) and 98.5% specificity (95% confidence interval, 92%-100%). The sensitivity of OSNA was significantly better than that of IC (80% vs 63%; P = .0229).

CONCLUSIONS

The OSNA breast cancer system proved to be highly accurate for the detection of metastatic breast cancer in axillary SLNs. Sensitivity was comparable to that predicted for conventional postoperative histologic examination at 2-mm intervals and was significantly more sensitive than IC. Automation, semiquantitative results enabling the differentiation of macrometastasis and micrometastasis, and rapid results render the assay suitable for intraoperative and/or permanent evaluation of SLNs.

Post-surgical treatment of early-stage breast cancer with electronic brachytherapy: an intersociety, multicenter brachytherapy trial

INTRODUCTION

Electronic brachytherapy (EBT) was developed to allow accelerated partial breast irradiation to be performed in a patient procedure room with minimal shielding. This observational, nonrandomized, multicenter study evaluated EBT as a post-surgical adjuvant radiation therapy for early stage breast cancer.

METHODS

This study included women aged 50 years or more with invasive carcinoma or ductal carcinoma in situ, tumor size ≤3 cm, negative lymph node status, and negative surgical margins. The endpoints were skin and subcutaneous toxicities, efficacy outcomes, cosmetic outcomes, and device performance. In this interim report, 1-month, 6-month, and 1-year follow-up data are available on 68, 59, and 37 patients, respectively.

RESULTS

The EBT device performed consistently, delivering the prescribed 34 Gy to all 69 patients (10 fractions/patient). Most adverse events were Grade 1 and included firmness, erythema, breast tenderness, hyperpigmentation, pruritis, field contracture, seroma, rash/desquamation, palpable mass, breast edema, hypopigmentation, telangiectasia, and blistering, which were anticipated. Breast infection occurred in two (2.9%) patients. No tumor recurrences were reported. Cosmetic outcomes were excellent or good in 83.9%-100% of evaluable patients at 1 month, 6 months, and 1 year.

CONCLUSION

This observational, nonrandomized, multicenter study demonstrates that this EBT device was reliable and well tolerated as an adjuvant radiation therapy for early stage breast cancer.

Update on DCIS outcomes from the American Society of Breast Surgeons accelerated partial breast irradiation registry trial

BACKGROUND

Since the initial reports on use of MammoSite accelerated partial breast irradiation (APBI) for treatment of ductal carcinoma in situ (DCIS), additional follow-up data were collected. We hypothesized that APBI delivered via MammoSite would continue to be well tolerated, associated with a good cosmetic outcome, and carry a low risk for recurrence in patients with DCIS.

MATERIALS AND METHODS

From 2002-2004, 194 patients with DCIS were enrolled in a registry trial to assess the MammoSite. Follow-up data were available for all 194 patients. Median follow-up was 54.4 months; 63 patients had at least 5 years of follow-up. Data obtained included patient-, tumor-, and treatment-related factors, and recurrence incidence.

RESULTS

Of the 194 patients, 87 (45%) had the MammoSite placed at lumpectomy; 107 patients (55%) had the device placed postlumpectomy. In the first year of follow-up, 16 patients developed a breast infection, though the method of device placement was not associated with infection risk. Also, 46 patients developed a seroma that was associated with applicator placement at the time of lumpectomy (P = 0.001). For patients with at least 5 years of follow-up, 92% had favorable cosmetic results. There were 6 patients (3.1%) who had an ipsilateral breast recurrence, with 1 (0.5%) experiencing recurrence in the breast and axilla, for a 5-year actuarial local recurrence rate of 3.39%.

CONCLUSIONS

During an extended follow-up period, APBI delivered via MammoSite continued to be well tolerated for patients with DCIS. Use of this device may make lumpectomy possible for patients who would otherwise choose mastectomy because of barriers associated with standard radiation therapy.