Patient Selection for Clinical Trials Eliminating Surgery for HER2-Positive Breast Cancer Treated with Neoadjuvant Systemic Therapy

BACKGROUND

Patients with epidermal growth factor receptor 2-positive (HER2+) breast cancer and pathologic complete response (pCR) after neoadjuvant systemic therapy (NST) may be candidates for nonoperative clinical trials if residual invasive and in situ disease are eradicated.

METHODS

This study analyzed 280 patients with clinical T1-2N0-1 HER2+ breast cancer who underwent NST followed by surgical resection to determine key characteristics of patients with pCR in the breast and lymph nodes compared with those with residual disease.

RESULTS

Of the 280 patients, 102 (36.4%) had pCR in the breast and lymph nodes after NST, and 50 patients (17.9%) had residual ductal carcinoma in situ (DCIS) in the breast only. For 129 patients (46.1%), DCIS was present on the pretreatment biopsy, and NST failed to eradicate the DCIS component in 64.3%. Patients with residual disease were more likely to have hormone receptor-positive (HR+) tumors than those with negative tumors (73.4% vs. 50.8%; p < 0.0001). Radiologic response (odds ratio [OR], 5.62; p = 0.002) and HR+ status (OR, 2.56; p < 0.0001) were predictive of residual disease. Combined imaging methods after NST had a sensitivity of 97.1% and a negative predictive value of 70.6% for detection of residual disease. Patients with invasive disease and DCIS shown on the pretreatment core biopsy were less likely than those without DCIS to achieve pCR in the breast (31% vs. 43%; p  = 0.038).

CONCLUSION

The study results delineate and identify unique characteristics associated with HER2+ breast cancers that are important in selecting patients for inclusion in clinical trials assessing nonoperative management after NST, and the low negative predictive value of imaging mandates image-guided biopsy for selection.

Sonographic features of benign and malignant axillary nodes post-neoadjuvant chemotherapy

The aim was to determine whether sonographic features of metastatic axillary lymph nodes predict pathologic nodal status post-neoadjuvant chemotherapy (NCT) and help to tailor less invasive surgical management of the axilla. Patients with biopsy-proven cN1 primary breast malignancy who received NCT between January 2011 and December 2014 and had performed ultrasound were included in this study. Sonographic features of biopsy-proven clipped metastatic axillary nodes pre- and post-NCT were retrospectively reviewed by two independent readers. Changes in lymph node shape, fatty hilum status, cortical thickness, and cortical echogenicity were compared in patients with and without nodal pathologic complete response (pCR) using univariate and multivariate logistic regression models. Inter-reader variation was analyzed to determine the reproducibility of data. Of the 195 patients included in the study, 75 (45%) showed nodal pCR and 90 (55%) persistent metastatic disease post-NCT. pCR was significantly more likely in lymph nodes with isoechoic or hypoechoic cortical echogenicity post-NCT, (P = .02), conversion to normal cortical thickness (P = .0001), and oval shape (odds ratio = 0.17, P = .004), compared to lymph nodes with anechoic cortical echogenicity, persistent or diffuse cortical thickening, and irregular shape, respectively. The overall accuracy of sonographic nodal features in the prediction of pCR was 65% (95% CI: 58%-72%). The overall accuracy of sonographic features of biopsy-proven metastatic axillary lymph nodes post-NCT is not sufficiently high to predict pCR of axillary nodal status and thereby should not be solely used in guiding less invasive surgical approaches to the axilla.

Neoadjuvant Radiotherapy to Facilitate Immediate Breast Reconstruction: A Systematic Review and Current Clinical Trials

BACKGROUND

Postmastectomy radiotherapy currently is used for locally advanced breast cancers that carry a high risk of locoregional failure. However, radiotherapy can have deleterious effects on immediate breast reconstruction (IBR). Neoadjuvant radiotherapy (NART) to facilitate postmastectomy IBR is an emerging new therapeutic sequence. A systematic review was undertaken to evaluate the current evidence on the feasibility and safety of this sequence.

METHODS

A comprehensive search of MEDLINE, EMBASE, Cochrane Library, Web of Science, and ClinicalTrials.gov from inception to 2018 was conducted, resulting in 592 records. The review included 18 retrospective and prospective studies of NART and IBR.

RESULTS

The majority of the studies used whole-breast radiotherapy with 50 Gy, conventionally fractionated, and waited 6-8 weeks before surgery. The IBR methods were varied, with both implant and autologous reconstructions. No intraoperative complications occurred, and the postoperative complication rates ranged from 3 to 36%. The partial and total flap loss rates were very low. Studies reporting cosmetic outcomes rated the majority of cases as good or excellent. The pathologic complete response rates ranged from 17 to 55%, and the locoregional recurrence rates were low (≤ 10%), with a short follow-up period. The current MD Anderson Cancer Center prospective clinical trial is described.

CONCLUSIONS

The initial results of NART and IBR demonstrate the safety of this treatment both technically and oncologically. Longer follow-up evaluation of these studies and larger prospective controlled clinical trials are needed to establish this new therapeutic sequence as a standard of care.

Excellent Locoregional Control in Inflammatory Breast Cancer With a Personalized Radiation Therapy Approach

PURPOSE

Inflammatory breast cancer (IBC) has been characterized by high locoregional recurrence (LRR) rates even after trimodality therapy. We recently reported excellent locoregional control among patients treated since formal dedication of an IBC-specific clinic and research program in 2006. Institutionally, a standard twice-daily (BID) dose escalation regimen for all patients with IBC was de-escalated in select cases in 2006 after review demonstrated that young age, incomplete response to neoadjuvant therapy, and positive margins identified subsets with maximal benefit from dose escalation. We report local control and toxicity rates specific to BID versus once-daily (QD) radiation therapy approaches.

METHODS AND MATERIALS

From a prospectively collected database, we identified 103 patients with nonmetastatic IBC who received trimodality therapy at our institution from 2007 to 2015. Descriptive statistics were used to describe the study cohort and compare retrospectively extracted rates of radiation therapy-associated toxicity. The actuarial rate of LRR-free survival was analyzed using the Kaplan-Meier method.

RESULTS

The median follow-up is 3.6 years. Thirty-nine patients (37.9%) received postmastectomy radiation therapy (PMRT) to the chest wall and undissected regional lymphatics in QD fractions (median dose, 50.0 Gy in 25 fractions [fx]; median boost dose, 10.0 Gy in 5 fx) and 64 patients (62.1%) received BID PMRT (median dose, 51.0 Gy in 34 fx; median boost dose, 15.0 Gy in 10 fx). Crude rates of toxicity were not different between patients treated with QD or BID PMRT. Two BID patients (3.1%) and no QD patients (0.0%) experienced LRR (P = .53). The 3- and 5-year LRR-free survival were 95.1% and 100.0% for BID and QD patients, respectively (P = .25).

CONCLUSIONS

Tailoring radiation therapy to clinical risk factors was associated with excellent locoregional control. De-escalation of PMRT from BID to QD was not clearly associated with reduced toxicity compared with BID, although retrospective data collection may limit this comparison.

Abstract GS4-04: Primary results of NSABP B-39/RTOG 0413 (NRG Oncology): A randomized phase III study of conventional whole breast irradiation (WBI) versus partial breast irradiation (PBI) for women with stage 0, I, or II breast cancer

Background: Conventional WBI after lumpectomy for early-stage breast cancer decreases ipsilateral breast tumor recurrence (IBTR), yielding comparable results to mastectomy. Accelerated PBI appears effective in reducing IBTR by treating only the tumor bed area. As the majority of IBTR occur at or in the vicinity of the tumor bed, we hypothesized that PBI would be as effective as WBI in controlling IBTR. The primary aim of NSABP B-39/RTOG 0413 was to determine if PBI provides equivalent local tumor control post lumpectomy compared to WBI in pts with early-stage breast cancer. The equivalency test was based on a 50% margin of increase in the hazard ratio (HR=1.5). Secondary endpoints included: overall survival (OS), recurrence-free interval (RFI), distant disease-free interval (DDFI), and toxicity.

Methods: Eligible pts had lumpectomy with histologically-free margins and 0-3 positive axillary nodes. Pts were stratified by stage, menopausal status, hormone receptor status, and intent to receive chemotherapy and then randomized to PBI or WBI. PBI was 10 fractions of 3.4-3.85 Gy, given twice daily with either brachytherapy or 3D external beam radiation. WBI was 50 Gy in 2 Gy fractions given daily with a sequential boost to the surgical cavity. Follow-up was every 6 mos for 5 yrs and then annually. All analyses were by intent-to-treat.

Results: From 3-21-05 to 4-16-13, 4216 pts were randomized: 2107 PBI; 2109 WBI. 61% were postmenopausal; 81% were hormone receptor-positive; 29% intended to receive chemotherapy. Stage distribution was: DCIS, 24%; invasive pN0, 65%; invasive pN1, 10%. As of 7-31-18, median follow-up was 10.2 yrs. There were 161 IBTRs as first events: 90 PBI v 71 WBI (HR 1.22; 90%CI 0.94-1.58). Per protocol-defined margin, to declare PBI and WBI equivalent regarding IBTR risk, the 90% CI for the observed HR had to lie entirely between 0.667 and 1.5. The percent of pts IBTR-free at 10 yrs was 95.2% PBI v 95.9% WBI. A statistically significant difference in the 10-yr RFI rate favored WBI (91.9% PBI v 93.4% WBI; HR 1.32; 95%CI 1.04-1.68; p=0.02). No statistically significant differences existed between PBI and WBI in DDFI (HR 1.31; 95%CI 0.91-1.91; p=0.15), OS (HR 1.10; 95%CI 0.90-1.35; p=0.35), or DFS (HR 1.12; 95%CI 0.98-1.29; p=0.11). Grade 3 toxicity was 9.6% PBI v 7.1% WBI, and grade 4-5 toxicity was 0.5% v 0.3%, respectively.

Discussion: PBI did not meet the criteria for equivalence to WBI in controlling IBTR based on the upper limit of the hazard ratio confidence interval. However, the absolute difference in 10-yr rate of IBTR was &lt;1% (4.8% PBI v 4.1% WBI). The risk of an RFI event was statistically significantly higher for PBI compared to WBI, but the absolute difference in 10-yr RFI rate was also small (8.1% PBI v 6.6% WBI). DDFI, OS, and DFS were not statistically different for PBI v WBI. Grade 3-5 toxicities, although low, were more common for PBI than WBI. The trial population was heterogeneous, ranging from Stage 0-2 breast cancer, and outcome by risk categories are being analyzed.

Support: U10CA180868, -180822, UG1CA189867.

Citation Format: Vicini FA, Cecchini RS, White JR, Julian TB, Arthur DW, Rabinovitch RA, Kuske RR, Parda DS, Ganz PA, Scheier MF, Winter KA, Paik S, Kuerer HM, Vallow LA, Pierce LJ, Mamounas EP, Costantino JP, Bear HD, Germaine I, Gustafson G, Grossheim L, Petersen IA, Hudes RS, Curran, Jr. WJ, Wolmark N. Primary results of NSABP B-39/RTOG 0413 (NRG Oncology): A randomized phase III study of conventional whole breast irradiation (WBI) versus partial breast irradiation (PBI) for women with stage 0, I, or II breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-04.

Surgeon perception versus reality: Opioid use after breast cancer surgery

BACKGROUND

Few guidelines exist for an opioid prescription after breast surgical oncology (BSO) procedures. We sought to characterize opioid prescribing and use patterns by surgery type.

METHODS

Patients (n = 332) undergoing BSO procedure were surveyed one week postoperatively for opioid use. The surgeons were surveyed about pain management preferences surgery type. CPT codes were collected for 2017 to calculate the amount of opioids used by surgery type relative to surgeon preference.

RESULTS

Mean oral morphine equivalent (OME) preferred prescription for surgeons who did not tailor prescriptions by surgery type (n = 7, group A) was 177, whereas for those who did tailor (n = 10, group B) varied from 137 to 257 OME. There was a significant difference in opioid use by surgery type: 32 OME for segmental mastectomy (SM) ± sentinel lymph node dissection (SLND), 63 for SM + axillary lymph node dissection (ALND), 76 for total mastectomy (TM) ± SLND, 115 for TM + ALND (P < 0.001). Considering the type of surgeries performed group A prescribers would have 229190 unused OME and group B would have 230826 in 1 year.

CONCLUSION

Wide variation in opioid use by BSO procedure type was noted with substantial unused OME regardless ofprescribing preference. Evidence-based guidelines are needed to tailor analgesic prescriptions according to the need.

OncotypeDX Recurrence Score Does Not Predict Nodal Burden in Clinically Node Negative Breast Cancer Patients

BACKGROUND

OncotypeDX recurrence score (RS)^® has been found to predict recurrence and disease-free survival in patients with node negative breast cancer. Whether RS is useful in guiding locoregional therapy decisions is unclear. We sought to evaluate the relationship between RS and lymph node burden.

METHODS

Patients with invasive breast cancer who underwent sentinel lymph node dissection from 2010 to 2015 were identified from a prospectively maintained database. Patients were excluded if they were clinically node positive or if they received neoadjuvant chemotherapy. RS was classified as low (< 18), intermediate (18-30), or high (> 30). The association between RS, lymph node burden, and disease recurrence was evaluated. Statistical analyses were performed in R version 3.4.0; p < 0.05 was considered significant.

RESULTS

A positive SLN was found in 168 (15%) of 1121 patients. Completion axillary lymph node dissection was performed in 84 (50%) of SLN-positive patients. The remaining 84 (50%) patients had one to two positive SLNs and did not undergo further axillary surgery. RS was low in 58.5%, intermediate in 32.6%, and high in 8.9%. RS was not associated with a positive SLN, number of positive nodes, maximum node metastasis size, or extranodal extension. The median follow-up was 23 months. High RS was not associated with locoregional recurrence (p = 0.07) but was significantly associated with distant recurrence (p = 0.0015).

CONCLUSIONS

OncotypeDX RS is not associated with nodal burden in women with clinically node-negative breast cancer, suggesting that RS is not useful to guide decisions regarding extent of axillary surgery for these patients.

Feasibility of fine-needle aspiration for assessing responses to chemotherapy in metastatic nodes marked with clips in breast cancer: A prospective registry study

BACKGROUND

Clips are often placed to mark axillary nodes with biopsy-confirmed metastases in patients with breast cancer. The evaluation of clipped nodes after chemotherapy can identify patients who have eradication of nodal disease. The goal of this study was to determine whether preoperative fine-needle aspiration (FNA) of clipped nodes after neoadjuvant chemotherapy (NAC) could predict the presence of residual disease.

METHODS

This prospective registry study enrolled 50 patients with a clip placed to mark nodes with biopsy-confirmed metastases who had completed NAC. Participants underwent FNA of the clipped node before seed-localized lymph node excision. FNA pathology was compared with surgical pathology.

RESULTS

There were 36 patients (72%) with residual disease on surgical pathology: 3 (8%) had a nondiagnostic aspirate, carcinoma was seen in 14 (39%), and 19 (53%) had a false-negative result. The sensitivity of FNA was 42.4%, its specificity was 100%, and its negative predictive value was 40.6%. In a univariate analysis, the odds of a true-positive result increased significantly with the mean initial size of the clipped node (odds ratio [OR], 4.3; P = .004) and the size of the metastatic focus after NAC (OR, 1.3; P = 0.003), whereas normalization of nodes after chemotherapy (OR, 0.1) and a lack of response on ultrasound (OR, 0.11) were associated with a false-negative result (P = .01).

CONCLUSIONS

FNA of marked nodes after chemotherapy has a high false-negative rate. This highlights the need for surgical staging of the axilla after NAC to assess the response.

American Society of Breast Surgeons' Practice Patterns After Publication of the SSO-ASTRO-ASCO DCIS Consensus Guideline on Margins for Breast-Conserving Surgery With Whole-Breast Irradiation

BACKGROUND

The SSO-ASTRO-ASCO consensus guideline on margins for breast-conserving surgery with whole breast irradiation in ductal carcinoma in situ (DCIS) recommended a 2-mm margin. We sought to determine the impact of guideline publication on clinician practice.

METHODS

A total of 3081 members of the American Society of Breast Surgeons (ASBrS) received a survey. Respondents' clinical practice type and duration, guideline familiarity, and margin width preferences before and after publication were assessed. Clinical practice pattern differences before and after publication were investigated using McNemar's test.

RESULTS

A total of 767 (24.9%) of those surveyed responded. Most (92.4%) indicated guideline familiarity. Of those familiar, re-excision preference for DCIS and a positive margin remained the same before (94.4%) and after (94.3%) publication (McNemar's test p = 1.0). Following publication, surgeons were more likely to avoid re-excision to achieve margins wider than 2-mm (82.3% pre versus 87.5% post, p = 0.002). More surgeons performed re-excision for a close margin with pure DCIS (25.9% pre versus 36.5% post, p < 0.001) and with DCIS with microinvasion (DCIS-M) (40.7% pre versus 52.3% post, p < 0.001). For patients with invasive disease with extensive intraductal component (EIC) and a close margin, preference to avoid re-excision was similar (51.2% per versus 55.2% post, p = 0.071).

CONCLUSION

Since guideline publication, surgeons are less likely to perform re-excision to obtain a margin greater than 2-mm and more likely to perform re-excision to obtain a 2-mm margin for both pure DCIS and DCIS-M. Preference to avoid re-excision with a close margin and EIC was similar before and after publication.

The Changing Paradigms for Breast Cancer Surgery: Performing Fewer and Less-Invasive Operations

Historically, through the conduct of prospective clinical trials, breast cancer surgeons have performed less radical breast and axillary surgeries with no survival decrement to our patients. Currently, other opportunities exist for the treating breast surgeon to do less. Possibilities include active surveillance for ductal carcinoma in situ, ablative therapy for small primary breast cancers, selective omission of a sentinel node biopsy, and selective elimination of breast surgery after neoadjuvant systemic therapy. Breast surgeons must be leaders in the development and testing of effective therapy with the least intervention possible.

Multidisciplinary Intraoperative Assessment of Breast Specimens Reduces Number of Positive Margins

BACKGROUND

Successful breast-conserving surgery requires achieving negative margins. At our institution, the whole surgical specimen is imaged and then serially sectioned with repeat imaging. A multidisciplinary discussion then determines need for excision of additional margins. The goal of this study was to determine the benefit of each component of this approach in reducing the number of positive margin.

METHODS

This single-institution, prospective study included ten breast surgical oncologists who were surveyed to ascertain whether they would have taken additional margins based their review of whole specimen images (WSI) and review of serially sectioned images (SSI). These results were compared with the multidisciplinary decisions (MDD) and pathology results. Margin status was defined using consensus guidelines.

RESULTS

One hundred surveys were completed. Margins on the original specimen were positive or close in 21%. After WSI, surgeons reported that they would have taken additional margins in 26 cases, reducing the number of positive/close margins from 21 to 13% (p < 0.001). After SSI, 52 would have taken additional margins; however, the number of positive/close margins remained 13%. MDD resulted in additional margins taken in 56 cases, reducing the number of positive/close margins to 7% (p < 0.001 compared with SSI).

CONCLUSIONS

While surgeon review of specimen radiographs can decrease the number of positive or close margins from 21 to 13%, more rigorous multidisciplinary, intraoperative margin assessment reduces the number of close or positive margins to 7%.

Incidence and Outcome of Breast Biopsy Procedures During Follow-up After Treatment for Breast Cancer

Importance

No comprehensive data are available regarding the frequency of breast biopsies performed during follow-up of treatment for invasive breast cancer.

Objective

To determine how often patients treated for breast cancer require breast biopsies during follow-up.

Design, Setting, and Participants

This nationwide population-based cohort study included 41 510 patients 64 years or younger in a commercial insurance database and 80 369 patients 66 years or older in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Patients were diagnosed with incident invasive breast cancer (stages I-III) from January 1, 2000, through December 31, 2011. Diagnosis and procedural codes were used to identify biopsy rates during follow-up. Data were analyzed from March 3 through October 3, 2017.

Main Outcomes and Measures

Cumulative incidence and adjusted risk of breast biopsy and subsequent breast cancer treatment were calculated using the Kaplan-Meier method and Cox proportional hazards regression. All statistical tests were 2 sided.

Results

Among the 121 879 patients in the study population, 5- and 10-year overall incidences of breast biopsy were 14.7% and 23.4%, respectively, in the commercial insurance cohort and 11.8% and 14.9%, respectively, in the SEER-Medicare cohort. The 5-year estimated incidence of breast biopsy was higher among women treated with brachytherapy (24.0% in the commercial insurance and 25.0% in the SEER-Medicare cohorts) than among those treated with whole-breast irradiation (16.7% in the commercial insurance and 15.1% in the SEER-Medicare cohorts) and persisted after multivariate adjustment in the commercial insurance (hazard ratio [HR], 1.53; 95% CI, 1.38-1.70; P < .001) and SEER-Medicare (HR, 1.76; 95% CI, 1.63-1.91; P < .001) cohorts. Adjuvant chemotherapy use (HR, 1.31; 95% CI, 1.25-1.37; P < .001) and patient age (>85 vs 66-69 years; HR, 0.40; 95% CI, 0.36-0.44; P < .001) in the SEER-Medicare cohort and endocrine therapy in the commercial insurance (HR, 0.88; 95% CI, 0.82-0.93; P < .001) and SEER-Medicare (HR, 0.91; 95% CI, 0.85-0.97; P = .002) cohorts were independently associated with biopsy. After unilateral mastectomy, the estimated 5-year contralateral breast biopsy rates were 10.4% and 7.7% in the commercial insurance and SEER-Medicare cohorts, respectively. Of the patients with breast biopsy, 1239 of 4158 patients (29.8%) in the commercial insurance cohort and 2258 of 9747 patients (23.2%) in the SEER-Medicare cohort underwent subsequent cancer treatment.

Conclusions and Relevance

These data on the need for breast biopsies during follow-up and subsequent treatments from a large cohort of women with commercial insurance and Medicare can be used in the context of therapy-planning discussions and survivorship expectations for patients with breast cancer.

Contralateral prophylactic mastectomy rate and predictive factors among patients with breast cancer who underwent multigene panel testing for hereditary cancer

Although multigene panel testing is increasingly common in patients with cancer, the relationship between its use among breast cancer patients with non-BRCA mutations or variants of uncertain significance (VUS) and disease management decisions has not been well described. This study evaluated the rate and predictive factors of CPM patients who underwent multigene panel testing. Three hundred and fourteen patients with breast cancer who underwent multigene panel testing between 2014 and 2017 were included in the analysis. Of the 314 patients, 70 elected CPM. Election of CPM by gene status was as follows: BRCA carriers (42.3%), non-BRCA carriers (30.1%), and VUS (10.6%). CPM election rates did not differ between non-BRCA carriers and BRCA carriers (P = 0.6205). Among non-BRCA carriers, negative hormone receptor status was associated with CPM (P = 0.0115). For those with a VUS, hormone receptor status was not associated with CPM (P = 0.1879). Although the rate of CPM between BRCA carriers and non-BRCA carriers was not significantly different, the predictors of CPM were different in each group. Our analyses shed the light on the increasing use of CPM among patients who are non-BRCA carriers as well those with a VUS. Our study elucidates the differing predictive factors of CPM election among BRCA carriers, non-BRCA carries, and those with a VUS. Our findings reveal the need for providers to be cognizant that non-BRCA genes and VUS drive women to elect CPM despite the lack of data for contralateral breast cancer risk associated with these genes.

Biopsy Feasibility Trial for Breast Cancer Pathologic Complete Response Detection after Neoadjuvant Chemotherapy: Imaging Assessment and Correlation Endpoints

PURPOSE

This study was designed to present the secondary imaging endpoints of the trial for evaluating mammogram (MMG), ultrasound (US) and image guided biopsy (IGBx) assessment of pathologic complete response (pCR) in breast cancer (BC) patients undergoing neoadjuvant chemotherapy (NAC).

METHODS

Patients with T1-3, N0-3, M0 triple-negative or HER2-positive BC who received NAC were enrolled in an Institutional Review Board-approved prospective, clinical trial. Patients underwent US and MMG at baseline and after NAC. Images were evaluated for residual abnormality and to determine modality for IGBx [US-guided (USG) or stereotactic guided (SG)]. Fine-needle aspiration and 9-G, vacuum-assisted core biopsy (VACBx) of tumor bed was performed after NAC and was compared with histopathology at surgery.

RESULTS

Forty patients were enrolled. Median age was 50.5 (range 26-76) years; median baseline tumor size was 2.4 cm (range 0.8-6.3) and 1 cm (range 0-5.5) after NAC. Nineteen patients had pCR: 6 (32%) had residual Ca²⁺ presurgery, 5 (26%) residual mass, 1 (5%) mass with calcifications, and 7 (37%) no residual imaging abnormality. Sensitivity, specificity, and accuracy of US, MMG, and IGBx for pCR were 47/95/73%, 53/90/73%, and 100/95/98%, respectively. Twenty-five (63%) patients had SGBx and 15 (37%) had US-guided biopsy (USGBx). Median number of cores was higher with SGBx (12, range 6-14) than with USGBx (8, range 4-12), p < 0.002. Positive predictive value for pCR was significantly higher for SG VACBx than for USG VACBx (100 vs. 60%, p < 0.05).

CONCLUSIONS

SG VACBx is the preferred IGBx modality for identifying patients with pCR for trials testing the safety of eliminating surgery.

Baseline factors predicting a response to neoadjuvant chemotherapy with implications for non-surgical management of triple-negative breast cancer

BACKGROUND

Patients with triple-negative breast cancer (TNBC) and a pathological complete response (pCR) after neoadjuvant chemotherapy may be suitable for non-surgical management. The goal of this study was to identify baseline clinicopathological variables that are associated with residual disease, and to evaluate the effect of neoadjuvant chemotherapy on both the invasive and ductal carcinoma in situ (DCIS) components in TNBC.

METHODS

Patients with TNBC treated with neoadjuvant chemotherapy followed by surgical resection were identified. Patients with a pCR were compared with those who had residual disease in the breast and/or lymph nodes. Clinicopathological variables were analysed to determine their association with residual disease.

RESULTS

Of the 328 patients, 36·9 per cent had no residual disease and 9·1 per cent had residual DCIS only. Patients with residual disease were more likely to have malignant microcalcifications (P = 0·023) and DCIS on the initial core needle biopsy (CNB) (P = 0·030). Variables independently associated with residual disease included: DCIS on CNB (odds ratio (OR) 2·46; P = 0·022), T2 disease (OR 2·40; P = 0·029), N1 status (OR 2·03; P = 0·030) and low Ki-67 (OR 2·41; P = 0·083). Imaging after neoadjuvant chemotherapy had an accuracy of 71·7 (95 per cent c.i. 66·3 to 76·6) per cent and a negative predictive value of 76·9 (60·7 to 88·9) per cent for identifying residual disease in the breast and lymph nodes. Neoadjuvant chemotherapy did not eradicate the DCIS component in 55 per cent of patients.

CONCLUSION

The presence of microcalcifications on imaging and DCIS on initial CNB are associated with residual disease after neoadjuvant chemotherapy in TNBC. These variables can aid in identifying patients with TNBC suitable for inclusion in trials evaluating non-surgical management after neoadjuvant chemotherapy.

Expanding Implementation of ACOSOG Z0011 in Surgeon Practice

BACKGROUND

After publication of American College of Surgeons Oncology Group (ACOSOG) Z0011, surgeons at our institution limited axillary surgery to sentinel lymph node dissection (SLND) in 76% of patients meeting trial eligibility criteria. Our study objective was to assess incorporation of the trial data into practice 5 years later.

PATIENTS AND METHODS

Patients with clinical T1-2, N0 invasive breast cancer undergoing breast conserving surgery were included. Comparisons were made between patients who underwent axillary lymph node dissection (ALND) and those that had no further surgery.

RESULTS

A total of 396 patients were included. Twelve percent (48/396) had positive SLNs; ALND was performed in 8% (4/48). Patients who underwent ALND were more likely to have 2 positive SLNs (50%, 2/4 vs. 2%, 1/44; P = .02) and microscopic extranodal extension (75%, 3/4 vs. 18%, 8/44; P = .03) than those that did not undergo ALND. Patients who underwent ALND also had a higher nomogram-predicted probability of having additional positive non-SLNs (53%) than those who had SLND alone (22%) (P = .0002). No patients had intraoperative assessment of SLNs performed.

CONCLUSIONS

The practice of omitting ALND in ACOSOG Z0011-eligible patients has expanded over 5 years. Clinicopathologic features continue to impact this decision. Intraoperative SLN assessment is no longer performed.

Identification of Patients With Documented Pathologic Complete Response in the Breast After Neoadjuvant Chemotherapy for Omission of Axillary Surgery

Importance

A pathologic complete response (pCR; no invasive or in situ cancer) occurs in 40% to 50% of patients with HER2-positive (HER2+) and triple-negative (TN) breast cancer. The need for surgery if percutaneous biopsy of the breast after neoadjuvant chemotherapy (NCT) indicates pCR in the breast (hereinafter referred to as breast pCR) has been questioned, and appropriate management of the axilla in such patients is unknown.

Objective

To identify patients among exceptional responders to NCT with a low risk for axillary metastases when breast pCR is documented who may be eligible for an omission of surgery clinical trial design.

Design, Setting, and Participants

This prospective cohort study at a single-institution academic national comprehensive cancer center included 527 consecutive patients with HER2+/TN (T1/T2 and N0/N1) cancer treated with NCT followed by standard breast and nodal surgery from January 1, 2010, through December 31, 2014.

Main Outcomes and Measures

Patients who achieved a breast pCR were compared with patients who did not based on subtype, initial ultrasonographic findings, and documented pathologic nodal status. Incidence of positive findings for nodal disease on final pathologic review was calculated for patients with and without pCR and compared using relative risk ratios with 95% CIs.

Results

The analysis included 527 patients (median age, 51 [range, 23-84] years). Among 290 patients with initial nodal ultrasonography showing N0 disease, 116 (40.4%) had a breast pCR and 100% had no evidence of axillary lymph node metastases after NCT. Among 237 patients with initial biopsy-proved N1 disease, 69 of 77 (89.6%) with and 68 of 160 (42.5%) without a breast pCR had no evidence of residual nodal disease (P < .01). Patients without a breast pCR had a relative risk for positive nodal metastases of 7.4 (95% CI, 3.7-14.8; P < .001) compared with those with a breast pCR.

Conclusions and Relevance

Breast pCR is highly correlated with nodal status after NCT, and the risk for missing nodal metastases without axillary surgery in this cohort is extremely low. These data provide the fundamental basis and rationale for management of the axilla in clinical trials of omission of cancer surgery when image-guided biopsy indicates a breast pCR.

DCIS Margins and Breast Conservation: MD Anderson Cancer Center Multidisciplinary Practice Guidelines and Outcomes

Recent published guidelines suggest that adequate margins for DCIS should be ≥ 2 mm after breast conserving surgery followed by radiotherapy (RT). Many groups now use this guideline as an absolute indication for additional surgery. This article describes detailed multidisciplinary practices including extensive preoperative/intraoperative pathologic/histologic image-guided assessment of margins, offering some patients with small low/intermediate grade DCIS no RT, the use/magnitude of radiation boost tailoring to margin width, and endocrine therapy for ER-positive DCIS. Use of these protocols over the past 20-years has resulted in 10-year local recurrence rates below 5% for patients with negative margins < 2 mm who received RT. Patients with margins < 2 mm who do not receive RT experience significantly higher local failure rates. Thus, there is not an absolute need to achieve wider negative surgical margins when < 2 mm for patients treated with RT and this should be determined by the multidisciplinary team. Utilization of these multidisciplinary treatment protocols and techniques may not be exportable and extrapolated to all hospitals, breast programs and systems as they can be complex and resource intensive.

Nonoperative Management for Invasive Breast Cancer After Neoadjuvant Systemic Therapy: Conceptual Basis and Fundamental International Feasibility Clinical Trials

With current advances in neoadjuvant systemic therapy (NST) and improved breast imaging, the potential of nonoperative therapy for invasive breast cancer has emerged as a viable option when utilizing meticulous image-guided percutaneous biopsy to document pathologic complete response. Feasibility clinical trials utilizing this approach are being performed by teams of investigators from single and multicenter/cooperative groups around the world. Imaging alone after NST lacks sufficient sensitivity and specificity in predicting pCR and therefore cannot be utilized for clinical selection of patients for omission of surgery. Imaging with adequate sampling after NST of the residual lesions (or around the remaining clip if a complete radiologic response occurs) appears to be essential in selecting patients with pCR to lower the false-negative rates based on initial reported feasibility studies to identify pCR without surgery that range from 5 to 49%. In this manuscript, recently completed, ongoing, and planned clinical feasibility trials and a new omission of surgery trial are described. Drastic rethinking of all diagnostic and therapeutic management strategies that are ordinarily utilized for patients who receive standard breast cancer surgery is required. A roadmap of essential questions and issues that will have to be resolved as the field of nonoperative breast cancer management advances is described in detail.

Use of Sentinel Lymph Node Dissection After Neoadjuvant Chemotherapy in Patients with Node-Positive Breast Cancer at Diagnosis: Practice Patterns of American Society of Breast Surgeons Members

BACKGROUND

The accuracy of sentinel lymph node dissection (SLND) in clinically node-positive patients who receive neoadjuvant chemotherapy has been investigated in clinical trials. This survey was designed to assess familiarity and impact of these trial findings into practice.

METHODS

American Society of Breast Surgeons members were invited by e-mail to complete an anonymous online survey. A total of 642 members responded (21% of 3090 eligible members). Results were summarized as proportions based on the number of responses to each question.

RESULTS

Respondents indicated knowledge of the Z1071 (86%), SENTINA (57%), and SN-FNAC (39%) trials. The published false negative rates (FNR) of the trials were correctly reported by 53% (336/638) of respondents. Before the trials, 45% (285/636) offered SLND compared with 85% (543/638) after the trials. In the 556 respondents who reported knowledge of at least one trial, 310 (56%) currently offer SLND to >50% of patients, 175 (31%) offer to <50%, and 70 (13%) routinely perform axillary lymph node dissection. Respondents who reported knowledge of the trials but did not change their practice to incorporate SLND (n = 67) cited concerns over lack of outcome data (64%), worries about FNR (42%), lack of resources (34%), or objections from radiation oncologists (25%), medical oncologists (18%), or other surgeons (8%).

CONCLUSIONS

The publication of trials evaluating SLND in clinically node-positive patients has resulted in changes in practice. Concerns over the FNR and lack of outcome data limit incorporation of SLND into practice by some surgeons.

A 10-Year Experience with Mastectomy and Tissue Expander Placement to Facilitate Subsequent Radiation and Reconstruction

BACKGROUND

An integrated approach to skin sparing mastectomy with tissue expander placement followed by radiotherapy and delayed reconstruction was initiated in our institution in 2002. The purpose of this study was to assess the surgical outcomes of this strategy.

METHODS

Between September 2002 and August 2013, a total of 384 reconstructions had a tissue expander placed at the time of mastectomy and subsequently underwent radiotherapy. Rates and causes of tissue expander explantation before, during, and after radiotherapy, as well as tumor specific outcomes and reconstruction approaches, were collected.

RESULTS

Median follow-up after diagnosis was 5.6 (range 1.3-13.4) years. In the study cohort, 364 patients (94.8%) had stage II-III breast cancer, and 7 patients (1.8%) had locally recurrent disease. The 5-year rates of actuarial locoregional control, disease-free survival, and overall survival were 99.2, 86.1, and 92.4%, respectively. The intended delayed-immediate reconstruction was subsequently completed in 325 of 384 mastectomies (84.6% of the study cohort). Of the remaining 59 tissue expanders, 1 was explanted before radiotherapy, 1 during radiotherapy, and 7 patients (1.8%) were lost to follow-up. Fifty patients (13.0%) required tissue expander explantation after radiation and before their planned final reconstruction, primarily due to cellulitis. Nonetheless, the cumulative rate of completed reconstructions was 89.6%. The median time from placement of the tissue expander until reconstruction was 12 (interquartile range 9-15) months.

CONCLUSIONS

Tissue expander placement at skin-sparing mastectomy in patients who require radiotherapy appears to be a viable strategy for combining reconstruction and radiotherapy.

Using the National Cancer Data Base for quality evaluation to assess adherence to treatment guidelines for nonmetastatic inflammatory breast cancer

BACKGROUND

Guidelines for the treatment of nonmetastatic inflammatory breast cancer (IBC) using trimodality therapy (TT) (chemotherapy, surgery, and radiotherapy) have remained largely unchanged since 2000. However, many patients with nonmetastatic IBC do not receive TT. It is unknown how patient-level (PL) and facility-level (FL) factors contribute to TT use.

METHODS

Using the National Cancer Data Base, patients with nonmetastatic IBC who underwent locoregional treatment from 2003 through 2011 were identified. The authors correlated PL factors, including demographic and tumor characteristics, with TT use. An observed-to-expected ratio for the number of patients treated with TT was calculated for each hospital by adjusting for significant PL factors. Hierarchical mixed effects models were used to assess the percentage of variation in TT use attributable to PL and FL factors, respectively.

RESULTS

Of the 542 hospitals examined, 55 (10.1%) and 24 (4.4%), respectively, were identified as significantly low and high outliers for TT use (P<.05). The percentage of the total variance in the use of TT attributable to the facility (11%) was nearly triple the variance attributable to the measured PL factors (3.4%). The nomogram generated from multivariate logistic regression of PL factors only allows a facility to assess TT use given their PL data.

CONCLUSIONS

FL factors rather than PL factors appear to contribute disproportionately to the underuse of TT in patients with nonmetastatic IBC. To improve treatment guideline adherence for patients with nonmetastatic IBC, it is critical to identify the specific FL factors associated with TT underuse. More organized FL intervention is required to train physicians and to build multidisciplinary teams. Cancer 2017;123:2618-25. © 2017 American Cancer Society.

Abstract LB-240: Circulating tumor cell (CTC) analysis in NRG oncology/RTOG 1014, repeat breast conserving treatment after in-breast recurrence (IBR)

Purpose: This was a phase II study designed to assess the safety of 3D-Conformal partial breast irradiation for local recurrence of breast carcinoma ≤ 3 cm in greatest dimension on pathologic specimen and ≤ 3 positive lymph nodes without extracapsular extension documented after evaluation. Detectable CTC incidence was unknown in patients (pts) with local recurrence only. CTCs were assessed pre and post treatment (tx) to determine incidence in this cohort, and determine correlation with outcome if feasible.

Methods: CTCS were assessed using the Cellsearch kit and assay prior to and within 3 weeks after completing radiotherapy. Nine cases were shipped after the recommended timeline and were analyzed after &gt; 72 hours. These data are included in the analysis. Outcome endpoints included IBR and distant metastases-free survival [DMFS; with or without IBR]. All analyses are descriptive. Due to small numbers, only frequencies of outcomes are reported.

Results: Forty-seven (81%) pts consented to participate in CTC analysis. The median follow-up for consenting pts was 3.66 years (min-max: 2.25 to 5.02 years). Variables were balanced between consenting and non-consenting pts. Thirty-one pts (66%) had paired pre and post-tx samples. Eight pts (17%) had detectable CTCs pre-tx; 32 (68%) were undetectable; and 7 (15%) were not evaluated. Eight pts (17%) had detectable CTCs post-tx; 26 (55%) were undetectable; and 13 (28%) were not evaluated. At both time points the majority of detectable CTC cases were found to have 1 CTC (5/8 pre, 6/8 post). In DCIS cases with CTC consent, 4/19 had pre-tx detectable CTCs and 3/14 had post-tx detectable CTCs. Among pts with both a pre and post-tx CTC result, 8 pts had a change in CTCs: 3 pts (10%) had detectable CTCs pre-tx and undetectable post-tx and 5 pts (16%) had undetectable CTCs pre-tx and detectable post-tx. Four of these were in pts with DCIS. Of those not consenting, there were 2 DMFS events and no IBR events. Two consenting pts had IBRs and 2 additional pts had DMFS. One IBR pt had undetectable pre and post-tx CTCs and one had undetectable CTCs pre-tx and detectable post-tx. One DMFS pt had detectable CTCs pre and post-tx while the other pt was not evaluated.

Conclusions: Considering consent and processing, a high proportion of paired samples were obtained. Incidence of detectable pre-tx CTCs is modestly lower than historical reports from cohorts with distant metastases. Low event rates preclude conclusions regarding association with outcome. Supported by NCI grants: U10CA180868, U10CA180822, UG1CA189867, U24CA180803

Citation Format: Wendy A. Woodward, Kathryn A. Winter, Douglas W. Arthur, Bruce G. Haffty, Henry M. Kuerer, Anthony Lucci, Summer Jackson, Eric A. Strom, Kathleen Beekman, Wayne H. Pinover, Frank G. Basile, Christine M. Fisher, Reshma Jagsi, Elin R. Sigurdson, Julia R. White. Circulating tumor cell (CTC) analysis in NRG oncology/RTOG 1014, repeat breast conserving treatment after in-breast recurrence (IBR) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-240. doi:10.1158/1538-7445.AM2017-LB-240

Body mass index mediates the prognostic significance of circulating tumor cells in inflammatory breast cancer

BACKGROUND

Obesity (BMI≥30) may be an etiologic and prognostic factor in inflammatory breast cancer (IBC). We examined the relationship between BMI, pathologic complete response (pCR), and circulating-tumor-cell (CTC) levels in IBC.

METHODS

Cohort included IBC patients diagnosed 2005-2015 who had neoadjuvant chemotherapy during a prospective trial on CTCs and pathologic review describing pCR. Chi-square, logistic regression, and Cox proportional hazards models were used to identify clinicopathologic associations with event-free survival (EFS).

RESULTS

Of 73 patients, 61 (84%) had CTC values, 22 (30%) achieved a pCR, and 39 (53%) were obese. There was no difference between obese and non-obese patients for pCR rates (31% vs. 29%, p = 0.90) or presence of CTCs (23% vs. 26%, p = 0.80). Among non-obese patients, CTCs were associated with worse EFS (HR 11.69, p < 0.01), but among obese patients, there was no difference in EFS between those with and without CTCs.

CONCLUSIONS

BMI mediates CTCs' prognostic significance in IBC.

Factors impacting the accuracy of intra-operative evaluation of sentinel lymph nodes in breast cancer

Sentinel lymph node dissection (SLND) is a standard axillary staging technique in breast cancer and intraoperative sentinel lymph node (SLN) assessment is important for decision-making regarding additional treatment and reconstruction. This study was undertaken to investigate clinicopathologic factors impacting the accuracy of intraoperative SLN evaluation. Records of patients with clinically node-negative, invasive breast cancer who underwent SLND with frozen section intraoperative pathologic evaluation from 2004 to 2007 were reviewed. Intraoperative SLN assessment results were compared to final pathology. Patients with positive SLNs that were initially reported as negative during intraoperative assessment were considered false negative (FN) events. Primary tumor histology, grade, receptor status, size, lymphovascular invasion (LVI), multifocality, neoadjuvant chemotherapy or hormonal therapy, number of SLNs retrieved, and SLN metastasis size were evaluated. The study included 681 patients, of whom 262 (38%) received neoadjuvant therapy. There were 183 (27%) patients who had a positive SLN on final pathology, of whom 60 (33%) had FN events. On univariate analysis, lobular histology, favorable histology, absence of LVI and micrometastasis were associated with a higher FN rate. On multivariate analysis, favorable and lobular histology and micrometastasis were independent predictors of FN events whereas LVI and receipt of neoadjuvant therapy were not statistically significant predictors. The accuracy of intraoperative SLN evaluation for breast cancer is affected by primary tumor histology and size of the SLN metastasis. There was no significant association between neoadjuvant therapy and the FN rate by intraoperative assessment. This information may be helpful in counseling patients about their risk for a FN intraoperative SLN assessment and for planning for immediate breast reconstruction in patients undergoing mastectomy.

A Standard Set of Value-Based Patient-Centered Outcomes for Breast Cancer: The International Consortium for Health Outcomes Measurement (ICHOM) Initiative

A major challenge in value-based health care is the lack of standardized health outcomes measurements, hindering optimal monitoring and comparison of the quality of health care across different settings globally. The International Consortium for Health Outcomes Measurement (ICHOM) assembled a multidisciplinary international working group, comprised of 26 health care providers and patient advocates, to develop a standard set of value-based patient-centered outcomes for breast cancer (BC). The working group convened via 8 teleconferences and completed a follow-up survey after each meeting. A modified 2-round Delphi method was used to achieve consensus on the outcomes and case-mix variables to be included. Patient focus group meetings (8 early or metastatic BC patients) and online anonymized surveys of 1225 multinational BC patients and survivors were also conducted to obtain patients' input. The standard set encompasses survival and cancer control, and disutility of care (eg, acute treatment complications) outcomes, to be collected through administrative data and/or clinical records. A combination of multiple patient-reported outcomes measurement (PROM) tools is recommended to capture long-term degree of health outcomes. Selected case-mix factors were recommended to be collected at baseline. The ICHOM will endeavor to achieve wide buy-in of this set and facilitate its implementation in routine clinical practice in various settings and institutions worldwide.

NRG Oncology-Radiation Therapy Oncology Group Study 1014: 1-Year Toxicity Report From a Phase 2 Study of Repeat Breast-Preserving Surgery and 3-Dimensional Conformal Partial-Breast Reirradiation for In-Breast Recurrence

PURPOSE

To determine the associated toxicity, tolerance, and safety of partial-breast reirradiation.

METHODS AND MATERIALS

Eligibility criteria included in-breast recurrence occurring >1 year after whole-breast irradiation, <3 cm, unifocal, and resected with negative margins. Partial-breast reirradiation was targeted to the surgical cavity plus 1.5 cm; a prescription dose of 45 Gy in 1.5 Gy twice daily for 30 treatments was used. The primary objective was to evaluate the rate of grade ≥3 treatment-related skin, fibrosis, and/or breast pain adverse events (AEs), occurring ≤1 year from re-treatment completion. A rate of ≥13% for these AEs in a cohort of 55 patients was determined to be unacceptable (86% power, 1-sided α = 0.07).

RESULTS

Between 2010 and 2013, 65 patients were accrued, and the first 55 eligible and with 1 year follow-up were analyzed. Median age was 68 years. Twenty-two patients had ductal carcinoma in situ, and 33 had invasive disease: 19 ≤1 cm, 13 >1 to ≤2 cm, and 1 >2 cm. All patients were clinically node negative. Systemic therapy was delivered in 51%. All treatment plans underwent quality review for contouring accuracy and dosimetric compliance. All treatment plans scored acceptable for tumor volume contouring and tumor volume dose-volume analysis. Only 4 (7%) scored unacceptable for organs at risk contouring and organs at risk dose-volume analysis. Treatment-related skin, fibrosis, and/or breast pain AEs were recorded as grade 1 in 64% and grade 2 in 7%, with only 1 (<2%) grade ≥3 and identified as grade 3 fibrosis of deep connective tissue.

CONCLUSION

Partial-breast reirradiation with 3-dimensional conformal radiation therapy after second lumpectomy for patients experiencing in-breast failures after whole-breast irradiation is safe and feasible, with acceptable treatment quality achieved. Skin, fibrosis, and breast pain toxicity was acceptable, and grade 3 toxicity was rare.

Performance of Mid-Treatment Breast Ultrasound and Axillary Ultrasound in Predicting Response to Neoadjuvant Chemotherapy by Breast Cancer Subtype

BACKGROUND

The primary objective was to determine whether mid-treatment ultrasound measurements of index breast tumors and index axillary nodes of different cancer subtypes associate with residual cancer burden (RCB).

METHODS

Patients with invasive breast cancer who underwent neoadjuvant chemotherapy and had pre-treatment and mid-treatment breast and axillary ultrasound were included in this single-institution, retrospective cohort study. Linear regression analysis assessed associations between RCB with (a) change in index breast tumor size, (b) change in index node size, and (c) absolute number of abnormal nodes at mid-treatment. Multivariate linear regression was used to calculate best-fit models for RCB.

RESULTS

One hundred fifty-nine patients (68 triple negative breast cancer [TNBC], 45 hormone receptor [HR]+/human epidermal growth factor receptor 2 [HER2]-, and 46 HR-/HER2+) were included. Median age at diagnosis was 50 years, range 30-76. Median tumor size was 3.4 cm, range 0.9-10.4. Pathological complete response/RCB-I rates were 36.8% (25/68) for TNBC patients, 24.4% (11/45) for HR+/HER2- patients, and 71.7% (33/46) for HR-/HER2+ patients. Linear regression analyses demonstrated associations between percent change in tumor ultrasound measurements at mid-treatment with RCB index score in TNBC and HR+/HER2- (p < .05) but not in HR-/HER2+ (p > .05) tumors and an association between axillary ultrasound assessment of number of abnormal nodes at mid-treatment with RCB index score across all subtypes (p < .05).

CONCLUSION

Performance characteristics of breast ultrasound associated with RCB vary by cancer subtype, whereas the performance characteristics of axillary ultrasound associated with RCB are consistent across cancer subtype. Breast and axillary ultrasound may be valuable in monitoring response to neoadjuvant therapy. The Oncologist 2017;22:394-401 IMPLICATIONS FOR PRACTICE: The differential performance characteristics of breast ultrasound by molecular subtype and the consistent performance characteristics of axillary ultrasound across molecular subtypes can have clinical utility in monitoring response to neoadjuvant therapy.

Molecular Profiling Using Breast Cancer Subtype to Plan for Breast Reconstruction

BACKGROUND

Molecular profiling using breast cancer subtype has an increasing role in the multidisciplinary care of the breast cancer patient. The authors sought to determine the role of breast cancer subtyping in breast reconstruction and specifically whether breast cancer subtyping can determine the need for postmastectomy radiation therapy and predict recurrence-free survival to plan for the timing and technique of breast reconstruction.

METHODS

The authors reviewed prospectively collected data from 1931 reconstructed breasts in breast cancer patients who underwent mastectomy between November of 1999 and December of 2012. Reconstructed breasts were grouped by breast cancer subtype and examined for covariates predictive of recurrence-free survival and need for postmastectomy radiation therapy.

RESULTS

Of the reconstructed breasts, 753 (39 percent) were luminal A, 538 (27.9 percent) were luminal B, 224 (11.6 percent) were luminal HER2, 143 (7.4 percent) were HER2-enriched, and 267 (13.8 percent) were triple-negative breast cancer. Postmastectomy radiation therapy was delivered in 69 HER2-enriched patients (48.3 percent), 94 luminal HER2 patients (42 percent), 200 luminal B patients (37.2 percent), 99 triple-negative breast cancer patients (37.1 percent), and 222 luminal A patients (29.5 percent) (p < 0.0001). Luminal A cases had better recurrence-free survival than HER2-enriched cases, and triple-negative breast cancer cases had worse recurrence-free survival than HER2-enriched cases. Luminal B and luminal HER2 cases had recurrence-free survival similar to that for HER2-enriched cases. Luminal A subtype was associated with the best recurrence-free survival. Subtyping may have improved the breast surgery planning for 33.1 percent of delayed reconstructions that did not require postmastectomy radiation therapy and 37 percent of immediate reconstructions that did require postmastectomy radiation therapy.

CONCLUSION

This study is the first publication in the literature to evaluate breast cancer subtype to stratify risk for decision making in breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Abstract P2-07-09: CPM rate among individuals with breast cancer who underwent multiplex gene testing for hereditary cancer: Single institution experience

Background: Availability of multiplex gene (MPG) testing for hereditary cancer has led to increase use of panel testing versus single gene testing for hereditary cancer. These panels include high, but also moderate penetrance genes. For some of these genes, associated cancer risk and risk management guidelines do not exist. Furthermore there is a high rate of variant of unknown significant (VUS) findings in non-BRCA genes. Currently, in the absence or minimal available data, health care providers and patients are faced with important risk management decisions, especially regarding preventive surgeries, such as prophylactic mastectomy. Currently, there is no data regarding prophylactic mastectomy rate among patients with breast cancer who underwent (MPG) testing. Therefore, our aim was to evaluate the rate of contralateral prophylactic mastectomy (CPM) in a cohort of individuals who underwent multiplex gene testing. Methods: Eight hundred thirty five patients with breast cancer who underwent MPG testing between the years 2013 and 2016 were identified using Institutional Clinical Cancer Genetics Database. Patients with pathogenic, likely pathogenic variants or who had a VUS were included in the analysis. Results: Of 835 patients with a diagnosis of breast cancer; 105 (13%) had a pathogenic or likely pathogenic mutation: 29 (28%) BRCA1, 26 (25%) BRCA2, 11 (11%) ATM, 2 (2%) BARD1, 3 (3%) BRIP, 9 (9%) CHEK2, 1 (1%) MSH2, 1 (1%) NBN, 5 (5%) PALB2, 4 (4%) PTEN, 1 (1%) RAD51C, 5 (5%) TP53, 4 (4%) CDH1, 2 (2%) MUTYH, 1 (1%) PMS2, 1 (1%) APC (1). A total of 102 (12%) VUS were found. Average age of diagnosis was 44 (Range 21-81). CPM rate was 32% (n=66) for the total cohort. Twenty nine % (n=19) of patients with non-BRCA mutations, 24.2% (n=16) with VUS and 46% (n=31) with BRCA mutations opted for CPM. Conclusion: Overall 32% of breast cancer patients with germline mutations or VUS opt for CPM at our institution. The rate for CPM in non- BRCA mutations carriers is high despite no available data regarding contralateral breast cancer risk and benefit of CPM. This finding should be validated in larger cohorts, including identification of reasons behind decision for CPM in these cohorts.

Citation Format: Elsayegh N, Gutierrez Barrera AM, Kuerer HM, Hernandez ND, Litton JK, Arun BK. CPM rate among individuals with breast cancer who underwent multiplex gene testing for hereditary cancer: Single institution experience [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-07-09.

Incremental Cancer Detection of Locoregional Restaging with Diagnostic Mammography Combined with Whole-Breast and Regional Nodal Ultrasound in Women with Newly Diagnosed Breast Cancer

RATIONALE AND OBJECTIVES

This study aims to determine if locoregional restaging with diagnostic mammography and ultrasound (US) of the whole breast and regional nodes performed for quality assurance in women with newly diagnosed breast cancer who were referred to a tertiary care center yields incremental cancer detection.

MATERIALS AND METHODS

An institutional review board-approved retrospective, single-institution database review was performed on the first 1000 women referred to our center in 2010 with a provisional breast cancer diagnosis. Locoregional restaging consisted of diagnostic full-field digital mammography combined with US of the whole breast and regional nodal basins. Bilateral whole-breast US was performed in women with contralateral mammographic abnormality or had heterogeneously or extremely dense parenchyma. Demographic, clinical, and pathologic factors were analyzed.

RESULTS

Final analyses included 401 women. Of the 401 women, 138 (34%) did not have their outside images available for review upon referral. The median age was 54 years (range 21-92); the median tumor size was 2.9 cm (range 0.6-18.0) for women whose disease was upstaged and 2.2 cm (range 0.4-15.0) for women whose disease was not upstaged. Incremental cancer detection rates were 15.5% (62 of 401) in the ipsilateral breast and 3.9% (6 of 154) in the contralateral breast (P < 0.0001). The total upstage rate was 25% (100 of 401). Surgical management changed from segmentectomy to mastectomy in 12% (50 of 401). The re-excision rate after segmentectomy was 19% (35 of 189).

CONCLUSIONS

Locoregional restaging with diagnostic mammography combined with whole-breast and regional nodal US that is performed for standardization of the imaging workup for newly diagnosed breast cancer patients can reduce underestimation of disease burden and impact therapeutic planning.

Optimizing Breast Cancer Adjuvant Radiation and Integration of Breast and Reconstructive Surgery

Postmastectomy radiotherapy (PMRT) reduces the risk of locoregional and distant recurrence and improves overall survival in women with lymph node-positive breast cancer. Because of stage migration and improvements in systemic therapy and other aspects of breast cancer care, the absolute benefit of PMRT and regional nodal irradiation may be small in some favorable subsets of patients with very low nodal burden, and newer consensus guidelines do not mandate PMRT in all node-positive cases. The use and need for PMRT may considerably complicate breast reconstruction after mastectomy and therefore mandates multidisciplinary input that takes into account patient choice given potential risk of acute and long-term toxicities, benefits, life expectancy, the biology of the tumor, plans for systemic therapy, and actual tumor burden. Management of axillary lymph node metastases is changing with selective use of axillary lymph node dissection for advanced disease, sentinel lymph node biopsy alone for clinically and pathologic node-negative cases receiving mastectomy, and targeted axillary dissection alone among patients with eradication of initial biopsy-proven nodal metastases with neoadjuvant systemic therapy use. In general, when the need for PMRT is anticipated, autologous reconstruction should be delayed. This comprehensive article reviews the current indications and implications regarding integration of breast cancer surgery and timing of reconstruction with optimum radiation delivery to achieve the best possible patient outcomes.

Clinical Utility of the 12-Gene DCIS Score Assay: Impact on Radiotherapy Recommendations for Patients with Ductal Carcinoma In Situ

Objective

The aim of this study was to determine the impact of the results of the 12-gene DCIS Score assay on (i) radiotherapy recommendations for patients with pure ductal carcinoma in situ (DCIS) following breast-conserving surgery (BCS), and (ii) patient decisional conflict and state anxiety.

Methods

Thirteen sites across the US enrolled patients (March 2014–August 2015) with pure DCIS undergoing BCS. Prospectively collected data included clinicopathologic factors, physician estimates of local recurrence risk, DCIS Score results, and pre-/post-assay radiotherapy recommendations for each patient made by a surgeon and a radiation oncologist. Patients completed pre-/post-assay decisional conflict scale and state-trait anxiety inventory instruments.

Results

The analysis cohort included 127 patients: median age 60 years, 80 % postmenopausal, median size 8 mm (39 % ≤5 mm), 70 % grade 1/2, 88 % estrogen receptor-positive, 75 % progesterone receptor-positive, 54 % with comedo necrosis, and 18 % multifocal. Sixty-six percent of patients had low DCIS Score results, 20 % had intermediate DCIS Score results, and 14 % had high DCIS Score results; the median result was 21 (range 0–84). Pre-assay, surgeons and radiation oncologists recommended radiotherapy for 70.9 and 72.4 % of patients, respectively. Post-assay, 26.4 % of overall recommendations changed, including 30.7 and 22.0 % of recommendations by surgeons and radiation oncologists, respectively. Among patients with confirmed completed questionnaires (n = 32), decision conflict (p = 0.004) and state anxiety (p = 0.042) decreased significantly from pre- to post-assay.

Conclusions

Individualized risk estimates from the DCIS Score assay provide valuable information to physicians and patients. Post-assay, in response to DCIS Score results, surgeons changed treatment recommendations more often than radiation oncologists. Further investigation is needed to better understand how such treatment changes may affect clinical outcomes.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-016-5583-7) contains supplementary material, which is available to authorized users.

Outcomes of Sentinel Lymph Node-Positive Breast Cancer Patients Treated with Mastectomy Without Axillary Therapy

PURPOSE

Early-stage breast cancer patients with minimal axillary disease identified by sentinel lymph node dissection (SLND) have low regional recurrence rates when treated with breast-conserving surgery and radiation therapy (XRT) and many avoid a completion axillary lymph node dissection (CLND). As the incidence of total mastectomy (TM) has increased, it has become important to characterize which TM patients with a positive SLN may not benefit from further axillary treatment.

METHODS

An institutional database was utilized to identify patients treated with a TM for invasive breast cancer and who had a positive SLN from 1994 to 2010. Clinicopathologic factors were analyzed. Regional recurrence rate, recurrence-free survival (RFS), and overall survival (OS) were determined.

RESULTS

A total of 525 patients with invasive breast cancer and a positive SLN were treated with TM, including 58 patients who did not have CLND or XRT and 12 patients who did not have CLND but did receive XRT. Median follow-up was 66 months. The incidence of regional recurrence was not significantly different for patients who received no further axillary treatment compared to those who underwent CLND without XRT or those treated with XRT without CLND (10 years rate: 3.8 vs. 1.6 and 0 % respectively). RFS and OS were not significantly different among patients who received no further axillary treatment compared to those who underwent CLND, XRT, or both.

CONCLUSIONS

In select patients with early-stage breast cancer treated with mastectomy with a positive SLN, CLND may be avoided without adversely affecting recurrence or survival.

Ten-Year Outcomes of Patients With Breast Cancer With Cytologically Confirmed Axillary Lymph Node Metastases and Pathologic Complete Response After Primary Systemic Chemotherapy

IMPORTANCE

The long-term effect of axillary pathologic complete response (pCR) on survival among women with breast cancer treated with primary systemic chemotherapy (PST) is unknown.

OBJECTIVE

To assess the long-term effect of axillary pCR on relapse-free survival (RFS) and overall survival (OS) in women with breast cancer with cytologically confirmed axillary lymph node metastases treated with PST.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analyzed the effect of axillary pCR on 10-year OS and RFS among all women who received a diagnosis of breast cancer stages II to III with cytologically confirmed axillary metastases between 1989 and 2007 who received PST at a large US comprehensive cancer center. Women were stratified by post-PST axillary status, and survival outcomes were estimated and compared according to response in the breast and axilla.

MAIN OUTCOMES AND MEASURES

Outcomes of interest were RFS and OS.

RESULTS

Of 1600 women treated, median (range) age at diagnisis was 49 (21-86) years. A total of 454 (28.4%) achieved axillary pCR. These patients were more likely to have human epidermal growth factor receptor 2 (HER2)-positive and triple-negative disease (P < .001), pCR in the breast (P < .001), high-grade tumors (P < .001), and lower clinical and pathologic T stage (P = .002). Ten-year OS rates were 84% (95% CI, 79%-88%) and 57% (95% CI, 54%-61%) (P < .001) and 10-year RFS rates 79% (95% CI, 74%-83%) and 50% (95% CI, 46%-53%) (P < .001) for patients with axillary pCR and residual axillary disease, respectively. For patients with axillary pCR, 10-year OS rates were 90% (95% CI, 84%-94%) for those with breast pCR and 72% (95% CI, 61%-80%) for those with residual breast disease (P < .001). For patients with residual axillary disease, 10-year OS rates were 66% (95% CI, 56%-74%) for patients with and 56% (95% CI, 52%-60%) for patients without breast pCR (P = .02). Of patients receiving HER2-targeted therapy for HER2-positive disease, 67.1% (100 of 149) achieved axillary pCR; 10-year OS rates were 92% (95% CI, 84%-96%) and 57% (95% CI, 20%-82%) (P = .003) and 10-year RFS rates 89% (95% CI, 81%-94%) and 44% (95% CI, 18%-68%) (P < .001) for those with axillary pCR and residual axillary disease, respectively.

CONCLUSIONS AND RELEVANCE

Axillary pCR was associated with improved 10-year OS and RFS. Patients with axillary and breast pCR after PST had superior long-term survival outcomes. Patients undergoing HER2-targeted therapy for HER2-positive disease had high rates of axillary pCR, and those with axillary pCR had excellent 10-year OS.

Operative and Oncologic Outcomes in 9861 Patients with Operable Breast Cancer: Single-Institution Analysis of Breast Conservation with Oncoplastic Reconstruction

BACKGROUND

Oncoplastic reconstruction is an approach that enables patients with locally advanced or adversely located tumors to undergo breast conserving surgery (BCS). The objectives were to identify the use of BCS with oncoplastic reconstruction (BCS + R) and determine the operative and oncologic outcomes compared with other breast surgical procedures for breast cancer.

METHODS

This retrospective cohort study interrogated a single institution's prospectively maintained databases to identify patients who underwent surgery for breast cancer between 2007 and 2014. Surgeries were categorized as BCS, BCS + R, total mastectomy (TM), or TM with immediate reconstruction (TM + R). Demographic and clinicopathologic characteristics and postoperative complications were analyzed.

RESULTS

There were 10,607 operations performed for 9861 patients. Median follow-up was 3.4 years (range, 0-9.1 years). The use of BCS + R had a nearly fourfold increase in the percentage of all breast cancer surgeries during the study period; 75 % of patients who underwent BCS + R had a T1 or T2 tumor. There was no difference in the use of BCS + R compared with BCS for any quadrant of the breast except the lower outer quadrant (11.1 vs. 6.8 %; p < .0001). BCS + R had a lower rate of seroma formation (13.4 vs. 18 %; p = .002) and positive or close margins compared with BCS (5.8 vs. 8.3 %; p = .04). There was no difference in overall survival or recurrence-free survival when comparing BCS and BCS + R.

CONCLUSIONS

Patients undergoing BCS + R are not disadvantaged in terms of complications and short-term (3-year) outcomes compared with BCS patients or patients who underwent TM.

Incremental cancer detection using breast ultrasonography versus breast magnetic resonance imaging in the evaluation of newly diagnosed breast cancer patients

OBJECTIVE

To compare the incremental cancer detection rate (ICDR) using bilateral whole-breast ultrasonography (BWBUS) vs dynamic contrast-enhanced MRI in patients with primary breast cancer.

METHODS

A retrospective database search in a single institution identified 259 patients with breast cancer diagnosed from January 2011 to August 2014 who underwent mammography, BWBUS and MRI before surgery. Patient characteristics, tumour characteristics and lesions seen on each imaging modality were recorded. The sensitivity, specificity and accuracy for each modality were calculated. ICDRs according to index tumour histology and receptor status were also evaluated. The effect of additional cancer detection on surgical planning was obtained from the medical records.

RESULTS

A total of 266 additional lesions beyond 273 index malignancies were seen on at least 1 modality, of which 121 (45%) lesions were malignant and 145 (55%) lesions were benign. MRI was significantly more sensitive than BWBUS (p = 0.01), while BWBUS was significantly more accurate and specific than MRI (p < 0.0001). Compared with mammography, the ICDRs using BWBUS and MRI were significantly higher for oestrogen receptor-positive and triple-negative cancers, but not for human epidermal growth factor receptor 2-positive cancers. 22 additional malignant lesions in 18 patients were seen on MRI only. Surgical planning remained unchanged in 8 (44%) of those 18 patients.

CONCLUSION

MRI was more sensitive than BWBUS, while BWBUS was more accurate and specific than MRI. MRI-detected additional malignant lesions did not change surgical planning in almost half of these patients.

ADVANCES IN KNOWLEDGE

BWBUS may be a cost-effective and practical tool in breast cancer staging.

Breast Cancer Clinical Trials: Past Half Century Moving Forward Advancing Patient Outcomes

Clinical trials in breast cancer have contributed immensely to the advancements of modern multimodal breast cancer treatment. Due to improved screening methods and more effective biologic-based tailored systemic therapies, the extent of surgery necessary for local and systemic control of disease is decreasing. Sequential trials for ductal carcinoma in situ (DCIS) have changed the management of this disease and are culminating in randomized active surveillance studies in an effort potentially to prevent overtreatment of low- and intermediate-grade disease. For patients with initial node-positive disease, clipping and marking of the biopsy-proven nodal metastases before the start of neoadjuvant chemotherapy can allow for selective node dissection based on the axillary response. With the current advances in primary systemic therapy, feasibility trials are beginning to investigate the potential of nonoperative therapy for invasive cancers with percutaneously documented pathologic complete response. This article presents a review and update on landmark clinical trials related to DCIS, the extent of axillary surgery in node-positive disease, and the integration of systemic therapy with local therapy.