Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy

Importance

Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown.

Objective

To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node.

Design, Setting, and Participants

In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis.

Exposure

Omission of ALND after SLNB or TAD.

Main Outcomes and Measures

The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed.

Results

A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55).

Conclusions and Relevance

The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

Premastectomy Radiotherapy and Immediate Breast Reconstruction: A Randomized Clinical Trial

Importance

Premastectomy radiotherapy (PreMRT) is a new treatment sequence to avoid the adverse effects of radiotherapy on the final breast reconstruction while achieving the benefits of immediate breast reconstruction (IMBR).

Objective

To evaluate outcomes among patients who received PreMRT and regional nodal irradiation (RNI) followed by mastectomy and IMBR.

Design, Setting, and Participants

This was a phase 2 single-center randomized clinical trial conducted between August 3, 2018, and August 2, 2022, evaluating the feasibility and safety of PreMRT and RNI (including internal mammary lymph nodes). Patients with cT0-T3, N0-N3b breast cancer and a recommendation for radiotherapy were eligible.

Intervention

This trial evaluated outcomes after PreMRT followed by mastectomy and IMBR. Patients were randomized to receive either hypofractionated (40.05 Gy/15 fractions) or conventionally fractionated (50 Gy/25 fractions) RNI.

Main Outcome and Measures

The primary outcome was reconstructive failure, defined as complete autologous flap loss. Demographic, treatment, and outcomes data were collected, and associations between multiple variables and outcomes were evaluated. Analysis was performed on an intent-to-treat basis.

Results

Fifty patients were enrolled. Among 49 evaluable patients, the median age was 48 years (range, 31-72 years), and 46 patients (94%) received neoadjuvant systemic therapy. Twenty-five patients received 50 Gy in 25 fractions to the breast and 45 Gy in 25 fractions to regional nodes, and 24 patients received 40.05 Gy in 15 fractions to the breast and 37.5 Gy in 15 fractions to regional nodes, including internal mammary lymph nodes. Forty-eight patients underwent mastectomy with IMBR, at a median of 23 days (IQR, 20-28.5 days) after radiotherapy. Forty-one patients had microvascular autologous flap reconstruction, 5 underwent latissimus dorsi pedicled flap reconstruction, and 2 had tissue expander placement. There were no complete autologous flap losses, and 1 patient underwent tissue expander explantation. Eight of 48 patients (17%) had mastectomy skin flap necrosis of the treated breast, of whom 1 underwent reoperation. During follow-up (median, 29.7 months [range, 10.1-65.2 months]), there were no locoregional recurrences or distant metastasis.

Conclusions and Relevance

This randomized clinical trial found PreMRT and RNI followed by mastectomy and microvascular autologous flap IMBR to be feasible and safe. Based on these results, a larger randomized clinical trial of hypofractionated vs conventionally fractionated PreMRT has been started (NCT05774678).

Trial Registration

ClinicalTrials.gov Identifier: NCT02912312.

Axillary Nodal Metastases Conversion and Perioperative Complications with Neoadjuvant Pembrolizumab Therapy in Triple-Negative Breast Cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is known to portend a worse prognosis compared with same-stage, hormone receptor-positive disease. However, with the recent change in practice to include pembrolizumab in neoadjuvant chemotherapy (NAC) for TNBC, an increase in pathologic complete responses (pCRs) has been reported. The perioperative repercussions of adding pembrolizumab to standard NAC regimens for TNBC are currently unknown. We aimed to explore the perioperative implications of adding pembrolizumab to standard NAC regimens for non-metastatic TNBC.

METHODS

This was a retrospective review of the perioperative outcomes in patients with non-metastatic TNBC treated with pembrolizumab-NAC from January 2018 to October 2022 conducted at a high-volume cancer center. Patient demographics, comorbidities, clinical and pathological staging, NAC treatment regimen, initiation, and completion, as well as date of surgery and postoperative complications were analyzed.

RESULTS

Of 87 patients, 67.8% had an overall pCR and 86% had an axillary pCR; 37.2% of cN+ patients were spared from axillary lymph node dissection. However, 24.1% of patients experienced surgical complications, 9% of patients were receiving steroids at the time of breast surgery secondary to adverse effects of pembrolizumab-NAC, and 7% underwent a change in the initial surgical plan such as omission of reconstruction.

CONCLUSION

Pembrolizumab-NAC has not only significant oncologic benefit but also noteworthy perioperative implications in the surgical management of TNBC.

Patient Interest in Exploring Nonsurgical Treatment Approaches for Early-Stage Breast Cancer: A Qualitative Study

PURPOSE

Advances in radiation therapy have enabled the ability to deliver ablative treatments, but there has been limited application of these treatments to early-stage breast cancers with a goal of omitting surgery. The purpose of this study was to explore patient interest in pursuing nonsurgical treatment approaches for their early-stage breast cancer.

METHODS AND MATERIALS

We conducted a qualitative study involving interviews with 21 patients with early-stage breast cancer who were eligible for participation in a phase 2 clinical trial offering omission of definitive surgery. Interviews were transcribed and an inductive, thematic analysis was performed by 3 independent reviewers to generate themes and subthemes.

RESULTS

Data analysis revealed the following factors that affected patient willingness and desire to explore nonsurgical treatment options: (1) perceptions and feelings about their cancer; (2) current quality of life and the level of support available in their daily life; (3) external conversations focusing on family members' and friends' experiences with cancer and/or cancer treatments; (4) personal health care experiences, including their current breast cancer diagnosis; (5) perceptions and feelings about their physicians; (6) conversations with their physicians about their treatment options; and (7) self-identified desire to direct care decisions. Specifically, patients verbalized fearing surgery and surgical recovery; wanting to preserve their breast(s); the prior negative surgical experiences of friends, family, and themselves; a desire to receive treatment per the latest research; wanting to match the level of treatment with the severity of their cancer; and other comorbidities as reasons for wanting to explore omitting surgery.

CONCLUSIONS

Our findings demonstrate an unmet need directed by patient interest to explore nonsurgical options for early-stage, biologically favorable breast cancer. These results may shape conversations around shared decision-making and clinical trial design, and result in more personalized treatment options for women with early-stage breast cancer.

Long-Term Outcomes and Predictors of Response in Breast Cancer Patients with Advanced Nodal Involvement

BACKGROUND

Advanced nodal disease is associated with poor prognosis. However, modern neoadjuvant systemic therapy (NST) regimens have resulted in higher pathologic complete response (pCR) rates, which are associated with improved survival. We sought to assess contemporary outcomes in patients with advanced nodal involvement and response to NST.

STUDY DESIGN

We conducted a single-institution, retrospective study of 521 patients with cN2-3 primary nonmetastatic breast cancer treated with NST followed by surgery and radiation from 2012 to 2018. Descriptive statistics, multivariate Cox regression, and Kaplan-Meier analyses were performed.

RESULTS

The mean age was 50.5 years, and median follow-up was 61 (4.7 to 197) months. The majority of patients had hormone receptor-positive (HR+)/HER2-negative tumors (HER2-; n = 242, 47.8%). Most were cT2 (n = 243; 46.6%) or cT3 (n = 139; 26.7%) and 73.3% (n = 382) had cN3 disease. Rate of axillary pCR was 34.2%, and breast and axillary pCR was 19.4% (n = 101). Event-free survival (EFS) at 5 years was 75.1% (95% CI, 0.71 to 0.79). Rate of locoregional recurrence was 6.7%; distant metastatic rate was 29.4%. Axillary pCR with or without breast pCR was significantly associated with longer EFS (p = 0.001). Achieving breast/axillary pCR was an independent predictor of improved EFS (hazard ratio 0.22, p < 0.0001). Having triple-negative disease was associated with worse EFS (hazard ratio 1.74, p = 0.008).

CONCLUSIONS

In a high-risk cohort of patients with cN2-3 disease, trimodality therapy was effective in achieving durable EFS. Approximately one-third of patients achieved axillary pCR, which was associated with improved survival. Further studies are needed to accurately determine axillary response in cN2-3 breast cancer after NST in order to develop de-escalation strategies to reduce morbidity associated with axillary surgery.

Extremely Low Incidence of Local-Regional Recurrences Observed Among T1-2 N1 (1 or 2 Positive SLNs) Breast Cancer Patients Receiving Upfront Mastectomy Without Completion Axillary Node Dissection

BACKGROUND

Completion axillary node dissection (CLND) is routinely omitted in cT1-2 N0 breast cancer treated with upfront, breast-conserving therapy and sentinel node biopsy (SLNB) showing one to two positive sentinel nodes (SLNs). The purpose of this study was to determine the incidence and impact of axillary treatment among patients treated with mastectomy in a contemporary cohort.

METHODS

A prospective, institutional database was reviewed from 2006 to 2015 to identify patients with T1-2 breast cancer treated with upfront mastectomy and SLNB found to have one to two positive SLNs. Patients were stratified by axillary therapy [including CLND and/or post-mastectomy radiation therapy (PMRT)], and clinicopathologic factors and incidence rates of local-regional and distant recurrence were analyzed.

RESULTS

A total of 548 patients were identified, including 126 (23%) without CLND. Rates of PMRT were similar between those with and without CLND (35.3% vs. 28.6%, p = 0.16). On multivariate analysis, two rather than one positive SLN, larger SLN metastasis size, frozen-section analysis of the SLNB, and adjuvant chemotherapy were significantly associated with receipt of CLND. At a median follow-up of 7 years, there were only two local-regional recurrences in the no-CLND group, of which only one was an axillary recurrence. The 5-years incidence rate of LRR was not significantly different for those with and without CLND (1.3% vs. 1.8%, p = 0.93).

CONCLUSIONS

We found extremely low rates of local-regional recurrence among those with T1-2 breast cancer undergoing upfront mastectomy with 1-2 positive SLNs. Further axillary surgery may not be indicated in selected patients treated with a multidisciplinary approach, including adjuvant therapies.

Prospective Clinical Trial of Premastectomy Radiotherapy Followed by Immediate Breast Reconstruction for Operable Breast Cancer

PURPOSE/OBJECTIVE(S)

Radiation delivered prior to mastectomy and autologous breast reconstruction may avoid the adverse effects of radiation on autologous donor tissue while providing the psychologic benefit of immediate reconstruction. We aimed to study the feasibility of premastectomy radiation therapy (PreMRT).

MATERIALS/METHODS

A total of 50 women enrolled in a prospective trial of preoperative radiation to the breast and regional nodes followed by mastectomy with axillary evaluation and immediate breast reconstruction. The trial was embedded in a randomized trial of hypofractionated versus conventionally fractionated regional nodal irradiation (NCT02912312). Eligible women enrolled from 2018-22, had cT0-T3 N0-3 breast cancer, and a pre-operative recommendation for radiation. The primary outcome was frequency of complete free flap loss. Mastectomy skin flap necrosis was assessed by validated SKIN grading score. The Satisfaction with Breast Cosmetic Outcomes Scales evaluated patient satisfaction with cosmetic result. Descriptive statistics and 95% exact confidence intervals were calculated.

RESULTS

One patient withdrew prior to any treatment and one elected not to have breast reconstruction. Median age of the 48 women completing PreMRT and reconstruction was 48 [range 31-72]. Most had ER-positive HER2-negative (77%), cT3 (54%) or cT2 (38%), cN1 (79%) disease and received 50 Gy in 25 fractions (n = 24) or 40.05 Gy in 15 fractions (n = 23). Four received 10-16 Gy internal mammary or infraclavicular boost. 35% VMAT, 48% matched photon-electron, and 17% partially-wide-tangent technique. Median time to surgery was 23 days [14-85]. Skin reaction delayed surgery for one patient. Most had skin-sparing mastectomy (92%) and axillary lymph node dissection (67%). 12 surgeons performed the reconstructions: 35 deep inferior epigastric perforators; 4 profunda artery perforator; 2 muscle-sparing transverse rectus abdominis myocutaneous; 1 latissimus dorsi (LD); 2 LD/implant; 2 LD/tissue expander (TE); and 2 subpectoral (SP) TE. There were no complete flap losses. Two patients (4.4%, 95% CI 0.5%-14.8%) with free flaps had partial flap loss with revision surgery. Both patients with SP TEs had infections and unplanned reoperation. The protocol was subsequently amended to not allow SP TE reconstruction. Eight patients had skin flap necrosis: 5 partial and 3 full thickness necrosis; only 1 required operative debridement. Seven had pathologic complete response. At six months 19/31 (61%) reported being "quite a bit" or "very much" satisfied with how they looked in the mirror clothed. There are no recurrences with a median follow up of 33 months [5-119].

CONCLUSION

Radiation treatment of the breast and lymph node basins prior to mastectomy with immediate autologous reconstruction is feasible. There were no autologous flap loses and complication rates are similar to reconstruction after radiation series. This promising strategy reduces time to autologous reconstruction and merits further prospective study.

Patient-Reported Outcomes of Omission of Breast Surgery Following Neoadjuvant Systemic Therapy: A Nonrandomized Clinical Trial

Importance

Patients should have an active role in decisions about pursuing or forgoing specific therapies in treatment de-escalation trials.

Objective

To evaluate longitudinal patient-reported outcomes (PROs) encompassing decisional comfort and health-related quality of life (HRQOL) among patients who elected to enroll in a clinical trial evaluating radiotherapy alone, without breast surgery, for invasive breast cancers with exceptional response to neoadjuvant systemic therapy (NST).

Design, Setting, and Participants

Prospective, single-group, phase 2 clinical trial at 7 US medical centers. Women aged 40 years or older with invasive cT1-2 N0-1 M0 triple-negative or human epidermal growth factor receptor 2 (ERBB2)-positive breast cancer with no pathologic evidence of residual disease following standard NST enrolled from March 6, 2017, to November 9, 2021. Validated PRO measures were administered at baseline and 6, 12, and 36 months post-radiotherapy. Data were analyzed from January to February 2023.

Interventions

PRO measures included the Decision Regret Scale (DRS), Functional Assessment of Cancer Therapy-Lymphedema (FACT-B+4), and Breast Cancer Treatment Outcomes Scale (BCTOS).

Main Outcomes and Measures

Changes in PRO measure scores and subscores over time.

Results

Among 31 patients, the median (IQR) age was 61 (56-66) years, 26 (84%) were White, and 26 (84%) were non-Hispanic. A total of 15 (48%) had triple-negative disease and 16 (52%) had ERBB2-positive disease. Decisional comfort was high at baseline (median [IQR] DRS score 10 [0-25] on a 0-100 scale, with higher scores indicating higher decisional regret) and significantly increased over time (median [IQR] DRS score at 36 months, 0 [0-20]; P < .001). HRQOL was relatively high at baseline (median [IQR] FACT-B composite score 121 [111-134] on a 0-148 scale, with higher scores indicating higher HRQOL) and significantly increased over time (median [IQR] FACT-B score at 36 months, 128 [116-137]; P = .04). Perceived differences between the affected breast and contralateral breast were minimal at baseline (median [IQR] BCTOS score 1.05 [1.00-1.23] on a 1-4 scale, with higher scores indicating greater differences) and increased significantly over time (median [IQR] BCTOS score at 36 months, 1.36 [1.18-1.64]; P < .001). At 36 months postradiotherapy, the cosmetic subscore was 0.45 points higher than baseline (95% CI, 0.16-0.74; P = .001), whereas function, pain, and edema subscores were not significantly different than baseline.

Conclusions and Relevance

In this nonrandomized phase 2 clinical trial, analysis of PROs demonstrated an overall positive experience for trial participants, with longitudinal improvements in decisional comfort and overall HRQOL over time and minimal lasting adverse effects of therapy.

Trial Registration

ClinicalTrials.gov Identifier: NCT02945579.

Eliminating Breast Surgery for Invasive Cancer with Exceptional Response to Neoadjuvant Systemic Therapy: Prospective Multicenter Clinical Trial Planned Initial Feasibility Endpoint

BACKGROUND

Response to neoadjuvant systemic therapy (NST) for breast cancer enables tailoring of subsequent therapy. Image-guided breast biopsy after NST can accurately predict a pathologic complete response (pCR). The feasibility phase of the clinical trial reported here assesses omission of breast surgery followed by radiotherapy in terms of local recurrence before trial expansion.

STUDY DESIGN

Women with unicentric, cT1-2 N0-1 M0 triple-negative (TNBC) or human epidermal growth factor receptor 2-positive breast cancer (HER2+BC) cancer with <2 cm residual disease on post-NST imaging were eligible to enroll. If no residual invasive or in situ disease was identified by image-guided, vacuum-assisted core biopsy (VACB), breast surgery was omitted, and radiotherapy delivered. The primary endpoint for the feasibility phase was ipsilateral breast tumor recurrence at 6 months. If any recurrence occurred during the feasibility phase the trial would halt.

RESULTS

Thirteen patients were enrolled from March 2017 to October 2018. The mean age was 60.8 years (range 51 to 75) and most patients were White (69.2%) and non-Hispanic/Latino (84.6%). All patients had invasive ductal carcinoma (6 TNBC, 7 HER2+BC). Mean tumor size was 2.4 cm (range 0.9 to 5.0) before NST and 0.7 cm (range 0 to 1.8) after NST. Seven patients (53.8%) had residual disease identified on VACB; the remaining 6 (46.2%) comprised the feasibility cohort. At a median follow-up of 44.3 months (range 41.3 to 51.3) there was no ipsilateral breast tumor recurrence in this cohort.

CONCLUSIONS

These early data suggest that omission of breast surgery in patients with invasive TNBC and HER2+BC with no evidence of residual disease on standardized VACB after NST is potentially feasible. Results from the expansion phase of this clinical trial will be reported per protocol prespecified analyses.

Predictors of Emergency Room Visits After Ambulatory Breast Cancer Surgery in the Medicare Population

BACKGROUND

Emergency department (ED) overuse is a large contributor to healthcare spending in the USA. We examined the rate of and risk factors for ED visits following outpatient breast cancer surgery.

PATIENTS AND METHODS

Using linked data from the Surveillance, Epidemiology, and End Results (SEER) program and Medicare, we identified women who underwent curative breast cancer surgery between 2003 and 2015. Our outcome of interest was ED visits within 30 days of surgery. Multivariate regression was used to evaluate the odds of ED visit while controlling for clinical and socioeconomic variables. Secondary analyses assessed admission from the ED as well as costs.

RESULTS

Of the 78,060 included patients, 5.1% returned to the ED, of which only 29.8% required hospital admission. Rate of ED visits increased with patient age. A higher percentage of Black patients returned to the ED compared with white patients (7.0% versus 5.0%, p < 0.001). Patients with higher income were less likely to visit the ED compared with those with lower income (OR 0.76, p < 0.001). Predictors of ED visits included: being unmarried (OR 1.18, p < 0.001), having stage 2 (OR 1.20, p < 0.001) or stage 3 cancer (OR 1.38, p < 0.001), and those with Charlson comorbidity score of 1 (OR 1.39, p < 0.001) or ≥ 2 (OR 2.29, p < 0.001).

CONCLUSION

While a substantial number of patients return to the ED following outpatient breast surgery, most do not require hospital admission, which indicates that a large proportion of these visits could have been avoided. We identified several clinical and socioeconomic predictors of postoperative ED visits, which will aid in the development of patient risk profiling tools.

Effectiveness Without Efficacy: Cautionary Tale from a Landmark Breast Cancer Randomized Controlled Trial

Background: "Old" randomized controlled trials established breast conserving therapy (BCT) and total mastectomy (TM) equivalence for treating early breast cancer, whereas recent literature report improved survival with BCT. To reconcile this, we performed a simulation study and re-analyzed B-06 trial data. Methods: We estimated the distributions for overall survival (OS), cumulative incidence functions for breast-cancer-specific death (BCSD) and other causes-specific death (OCSD) by BCT and TM. The restricted mean survival time (RMST) difference and hazard ratio between the two arms were estimated. Given the estimated distributions, we simulated cause-specific death times from each arm, evaluating the power to test treatment difference in OS, BCSD, and OCSD with different sample sizes, follow-up times, and a modified setting by simulating BCT-arm OCSD times from the distribution of patients not receiving radiation. Results: With 200 months follow-up, the average BCT-over-TM gain measured by RMST was 3.7 months for OS and 4.5 months for BCSD. Increasing the trial size to 5,000 per arm, there is a 79.2% chance to detect the OS benefit with RMST and 92.4% for BCSD. A nonproportional increase of OCSD in BCT compared to TM was observed after 144 months, and particularly after 200 months post treatments. When OCSD times of BCT were simulated using patients not receiving radiation, the estimated OS gain increased to 4.4 months, and the power increased to 92.2%. Conclusions: The late excess other-cause-death, likely due to radiation, in the BCT arm and sample size constraints limited the power to report BCT superiority. Given radiation delivered in the era of B-06 trial, BCT and TM remain largely equivalent.

Long-term Oncologic Outcomes in Patients with Inflammatory Breast Cancer with Supraclavicular Nodal Involvement

BACKGROUND

Inflammatory breast cancer (IBC) is a rare and aggressive subtype of breast cancer characterized by rapid progression and early metastasis, often with advanced nodal locations, including the supraclavicular (SCV) nodal basin. Previously considered M1 disease, ipsilateral clinical supraclavicular node involvement (N3c) disease is now considered locally advanced disease and warrants treatment with intent to cure. The objective of this study was to evaluate the long-term outcomes of patients with IBC and N3c disease.

PATIENTS AND METHODS

This study was conducted using a prospectively collected database of all patients with IBC treated at a dedicated cancer center from 2007 to 2019. Surgical patients with SCV nodal involvement and complete follow-up were identified. Our primary outcome was 5-year overall survival (OS). Multivariate Cox proportional hazards models were used to determine predictors for survival. Event-free survival (EFS) and OS were calculated using the Kaplan-Meier method.

RESULTS

There were 70 patients who met inclusion criteria. All patients underwent comprehensive trimodality therapy. The majority of patients had complete (66.2%) radiologic response in the SCV nodal basins following neoadjuvant therapy. Six patients (8.6%) had a locoregional recurrence, with two (2.9%) occurring in the supraclavicular fossa. The 5-year OS was 60.2% [95% confidence interval (CI) 47.7-72.7%]. Increasing age (hazard ratio 2.7; p = 0.03) and triple-negative subtype (hazard ratio 4.9; p = 0.03) were associated with poor OS. The 5-year EFS was 56.1% (95% CI 40.9-68.8%). The presence of more than ten positive axillary nodes on final surgical pathology (hazard ratio 5.5; p = 0.01) predicted poor EFS.

CONCLUSIONS

With comprehensive trimodality therapy and multidisciplinary team approach, patients with IBC with supraclavicular nodal involvement experience excellent locoregional control and favorable survival.

A multi-institutional prediction model to estimate the risk of recurrence and mortality after mastectomy for T1-2N1 breast cancer

Background

Post‐mastectomy radiation therapy (PMRT) in women with pathologic stage T1‐2N1M0 breast cancer is controversial.

Methods

Data from five North American institutions including women undergoing mastectomy without neoadjuvant therapy with pT1‐2N1M0 breast cancer treated from 2006 to 2015 were pooled for analysis. Competing‐risks regression was performed to identify factors associated with locoregional recurrence (LRR), distant metastasis (DM), overall recurrence (OR), and breast cancer mortality (BCM).

Results

A total of 3532 patients were included for analysis with a median follow‐up time among survivors of 6.8 years (interquartile range [IQR], 4.5–9.5 years). The 2154 (61%) patients who received PMRT had significantly more adverse risk factors than those patients not receiving PMRT: younger age, larger tumors, more positive lymph nodes, lymphovascular invasion, extracapsular extension, and positive margins (p < .05 for all). On competing risk regression analysis, receipt of PMRT was significantly associated with a decreased risk of LRR (hazard ratio [HR], 0.21; 95% confidence interval [CI], 0.14–0.31; p < .001) and OR (HR, 0.76; 95% CI, 0.62–0.94; p = .011). Model performance metrics for each end point showed good discrimination and calibration. An online prediction model to estimate predicted risks for each outcome based on individual patient and tumor characteristics was created from the model.

Conclusions

In a large multi‐institutional cohort of patients, PMRT for T1‐2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision‐making regarding PMRT in this population.

In a large multi‐institutional cohort of patients, post‐mastectomy radiation therapy (PMRT) for T1‐2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision‐making regarding PMRT in this population.

To Look or Not to Look? Yes to Nodal Ultrasound!

Knowledge of axillary nodal status is highly important for correct staging and treatment planning in patients with breast cancer. Axillary US is a recognized highly specific and cost-effective tool for assessing nodal status and guiding appropriate treatment. Axillary US imaging with US-guided biopsy is routinely performed throughout the world. However, because of recent developments in the surgical management of the axilla in patients with newly diagnosed breast cancer (American College of Surgeons Oncology Group [ACOSOG] Z0011 trial) and in patients with breast cancer receiving neoadjuvant systemic therapy (ACOSOG Z1071, SENTinel NeoAdjuvant [SENTINA] and Sentinel Node biopsy aFter NeoAdjuvant Chemotherapy [SN FNAC] trials), some have questioned the utility of axillary US for nodal staging. Here, we review the evidence to date supporting the additional value of axillary US for patients with breast cancer. Nodal US in patients with newly diagnosed breast cancer is useful for staging; in a significant proportion of patients, nodal US identifies additional axillary level II or level III nodal disease, which allows for appropriate treatment of disease. Furthermore, ongoing clinical trials may show that axillary surgery can be omitted in patients with negative findings on axillary US. In patients with lymph node-positive disease undergoing neoadjuvant systemic therapy, nodal US can guide the approach to axillary surgery. A more personalized patient approach, taking into the account tumor biology, among other factors, may help to mitigate the controversy surrounding the role of axillary US in breast cancer patients.

Randomized Phase III Trial Evaluating Radiation Following Surgical Excision for Good-Risk Ductal Carcinoma In Situ: Long-Term Report From NRG Oncology/RTOG 9804

PURPOSE

To our knowledge, NRG/RTOG 9804 is the only randomized trial to assess the impact of whole breast irradiation (radiation therapy [RT]) versus observation (OBS) in women with good-risk ductal carcinoma in situ (DCIS), following lumpectomy. Long-term results focusing on ipsilateral breast recurrence (IBR), the primary outcome, are presented here.

PATIENTS AND METHODS

Eligible patients underwent lumpectomy for DCIS that was mammogram detected, size ≤ 2.5 cm, final margins ≥ 3 mm, and low or intermediate nuclear grade. Consented patients were randomly assigned to RT or OBS. Tamoxifen use was optional. Cumulative incidence was used to estimate IBR, log-rank test and Gray's test to compare treatments, and Fine-Gray regression for hazard ratios (HRs).

RESULTS

A total of six hundred thirty-six women were randomly assigned from 1999 to 2006. Median age was 58 years and mean pathologic DCIS size was 0.60 cm. Intention to use tamoxifen was balanced between arms (69%); however, actual receipt of tamoxifen varied, 58% RT versus 66% OBS (P = .05). At 13.9 years' median follow-up, the 15-year cumulative incidence of IBR was 7.1% (95% CI, 4.0 to 11.5) with RT versus 15.1% (95% CI, 10.8 to 20.2) OBS (P = .0007; HR = 0.36; 95% CI, 0.20 to 0.66); and for invasive LR was 5.4% (95% CI, 2.7 to 9.5) RT versus 9.5% (95% CI, 6.0 to 13.9) OBS (P = .027; HR = 0.44; 95% CI, 0.21 to 0.91). On multivariable analysis, only RT (HR = 0.34; 95% CI, 0.19 to 0.64; P = .0007) and tamoxifen use (HR = 0.45; 95% CI, 0.25 to 0.78; P = .0047) were associated with reduced IBR.

CONCLUSION

RT significantly reduced all and invasive IBR for good-risk DCIS with durable results at 15 years. These results are not an absolute indication for RT but rather should inform shared patient-physician treatment decisions about ipsilateral breast risk reduction in the long term following lumpectomy.

Impact of the early COVID-19 pandemic on Breast Surgical Oncology fellow education

INTRODUCTION

The early COVID-19 pandemic rapidly transformed healthcare and medical education. We sought to evaluate the professional and personal impact of the pandemic on 2019-2020 Breast Surgical Oncology (BSO) fellows in Society of Surgical Oncology approved programs to capture the experience and direct future changes.

METHODS

From July 15, 2020 to August 4, 2020 a survey was administered to the American Society of Breast Surgeons' fellow members. The survey assessed the impact of the pandemic on clinical experience, education/research opportunities, personal health/well-being, and future career. Responses were collected and aggregated to quantify the collective experience of respondents.

RESULTS

Twenty-eight of fifty-seven (54%) eligible fellows responded. Twenty-one (75%) indicated the clinical experience changed. Twenty-seven (96%) reported less time spent caring for ambulatory breast patients and sixteen (57%) reported the same/more time spent in the operating room. Fourteen (50%) stated their future job was impacted and eight (29%) delayed general surgery board examinations. Stress was increased in 26 (93%). Personal health was unaffected in 20 (71%), and 3 (10%) quarantined for COVID-19 exposure/infection.

CONCLUSION

The COVID-19 pandemic altered the clinical experience of BSO fellows; however, the operative experience was generally unaffected. The creation of frameworks and support mechanisms to mitigate potential challenges for fellows and fellowship programs in the ongoing pandemic and other times of national crisis should be considered.

Clinical Course of Breast Cancer Patients with Local-Regional Progression During Neoadjuvant Systemic Therapy

BACKGROUND

Neoadjuvant systemic therapy (NST) is standard for locally advanced breast cancer and is now frequently considered for those with early-stage and node-positive disease. We aimed to evaluate the treatment course and outcomes in patients with disease progression during NST.

METHODS

Patients diagnosed with unilateral stage I-III breast cancer between 2005 and 2015 with documented local-regional progression while receiving NST, by clinical examination and/or imaging after two or more cycles of chemotherapy, were identified from a prospective database, stratified by receipt of surgery and outcomes analyzed.

RESULTS

Of 6362 patients treated with NST during the study period, 124 (1.9%) developed disease progression. At a median live follow-up of 71 months, 23.4% were alive without disease and 70.2% had died from breast cancer. Median overall survival (OS) time for patients with progression was 26 months and median distant disease-free survival (DFS) was 14 months. Triple-negative breast cancer was associated with a higher likelihood of death (p < 0.001) and development of distant metastasis (p = 0.002). Among patients who had surgery (104, 89.3%), 40 (38.5%) developed local-regional recurrence, 67 (64.4%) developed distant metastasis, and 69 (66.3%) died from breast cancer. Median OS and median distant DFS in this subgroup was 31 and 16 months, respectively.

CONCLUSIONS

High rates of local-regional and distant failure were seen following disease progression while receiving NST. This suggests aggressive tumor biology and the need to study novel systemic therapies. Poor survival outcomes despite surgical management highlight the importance of careful patient selection when considering operative intervention after progression while receiving NST.

Contralateral Axillary Metastasis in Patients with Inflammatory Breast Cancer

BACKGROUND

Nearly one-third of patients with inflammatory breast cancer (IBC) present with de novo stage IV disease. There are limited data on frequency and clinical outcomes of contralateral axillary metastasis (CAM) in IBC with no consensus diagnostic and treatment guidelines.

PATIENTS AND METHODS

Frequency of synchronous CAM was calculated in unilateral IBC patients at a single center (10/2004-6/2019). Clinicopathologic variables, diagnostic evaluation, treatment received, and overall survival (OS) were assessed and compared.

RESULTS

Of 588 unilateral IBC patients, 49 (8.3%) had synchronous CAM. Of these, 32 (65.3%) also presented with metastatic disease at another distant site. CAM was not associated with age, tumor laterality, breast cancer subtype, grade, or cN stage (p > 0.05). The sensitivity/specificity to detect CAM was as follows: mammography (18.2%/99.2%), ultrasound (92.3%/95.5%), PET (90.1/99.1%), and MRI (76.0%/98.6%). Following systemic therapy, 22 patients had contralateral axillary surgery, and 18 received adjuvant contralateral nodal radiation. On multivariable analysis including tumor receptor subtypes, patients with stage IV-isolated CAM has statistically similar survival to stage III patients (HR 1.37, 95% CI 0.70-2.69, p = 0.36). Patients with Stage IV non-CAM (HR 2.18, 95% CI 1.66-2.85, p < 0.001) and stage IV-CAM plus other distant metastasis (HR 2.57, 95% CI 1.59-4.16, p < 0.001) had higher risk of death (reference: stage III disease).

CONCLUSIONS

CAM in IBC was diagnosed in 8.3% of patients at presentation and was best identified by ultrasound and PET. We recommend routine contralateral axillary ultrasound as part of staging for all IBC patients. Diagnosis of CAM is a key first step toward much-needed prospective clinical trials evaluating management and outcomes of CAM in IBC.

Abstract PS1-17: Comparing survival differences between breast-conserving therapy and mastectomy in patients with early-stage breast cancer undergoing upfront surgery

Background: Over the last decade, patients with early-stage breast cancer have been undergoing total mastectomy (TM) with increasing frequency. Our center reported that local recurrence rates with breast conserving therapy (BCT) declined throughout the 27-year period: from 7.1% for patients treated during 1970–1984 to 1.3% for patients treated during 1994–1996. More recently, several groups have published slightly improved survival rates in patients undergoing BCT compared with TM. The aim of this study was to evaluate trends in TM rates and compare overall survival (OS), distant metastasis-free survival (DMFS), local-regional recurrence (LRR) and disease-specific survival (DSS) between BCT and TM in patients with early-stage breast cancer undergoing upfront surgery. Methods: We identified women with clinical stage T1–2, N0–1, M0 breast cancer who underwent surgery as first treatment modality from 1/1/2000 to 12/31/2014 at our center. TM rates and survival outcomes were evaluated. Because the decision for surgery for those patients was not random, differences in patient, tumor and treatment characteristics with respect to surgery types were adjusted using inverse probability weighting (IPW) based on propensity scores. Variables in the model included age at diagnosis, clinical tumor T category, clinical nodal category, estrogen receptor (ER), human epidermal growth factor receptor 2 (HER2) status and year of surgery, and a multinomial logit model was used for surgery treatment assignment and a Gamma model was used for the time to censor. IPW models were used to adjust for impact of surgery types on survival outcomes. Similar analysis was used in 6 subsets: Stage I & hormone receptor (HR)+/HER2-, Stage I & HER2+, Stage I &triple negative breast cancer (TNBC), Stage II & HR+/HER2-, Stage II & HER2+, Stage II & TNBC. Patients undergoing TM with RT were excluded from subset analysis due to small sample size.

Results: A total of 8,256 patients were included, of them, 4701 (56.9%) underwent BCT, 2862 (34.7%) underwent TM without RT and 693 (8.4%) underwent TM+RT. Patients who underwent TM were younger and were more likely to have larger tumors, positive lymph nodes, higher grade, and HER2-positive tumors. TM rates increased in patients &lt;=50 years old from 2006-2013. At a median follow-up time of 6.1 years, multivariable Cox model showed that patients who underwent BCT had improved OS (HR: 0.8,95%CI: 0.7-0.99, P=0.02) and had a similar DSS, DMFS, and LRR compared to patients who underwent TM without RT. After IPW adjusting, patients undergoing BCT had a slightly worse DSS (RR: 1.2, 95%CI: 1.02-1.4, P=0.03) and similar OS, DMFS and LRR compared to patients underwent TM without RT in the whole cohort. In subset analyses, after IPW adjusting, there were no survival differences in OS, DSS, and DMFS between TM without RT and BCT. Patients with TNBC undergoing BCT had a lower LRR compared to TM (RR: 0.4, 95% CI: 0.3-0.6, P&lt;0.001) regardless of clinical stage. Conclusions: In whole cohort, after IPW adjusting, patients undergoing BCT had a slightly worse DSS compared to patients underwent TM without RT, and those differences in DSS have disappeared in the subset analysis. LRR was lower in patients with TNBC breast cancer undergoing BCT although there as a similar OS, DSS and DMFS compared with TM in subset analysis. These contemporary data may help physicians in surgical decision making for patients who are candidates for either TM or BCT.

Table 1. Results from multivariable Cox models for factors associated with survival outcomes and IPW adjusted models for factors associated with survival outcomesCox ModelIPW adjusting modelsFactorsHRP95%CIRRP95% CIOSSurgery typeTM without RTBCT0.80.020.70.991.01.00.9-1.1TM with RT1.00.960.81.31.10.60.9-1.3DSSSurgery typeTM without RTRefBCT1.10.40.81.51.20.031.02-1.4TM with RT1.70.0051.22.61.30.021.04-1.6DMFSSurgery typeTM without RTRefBCT1.10.40.91.41.00.50.9-1.2TM with RT1.70.0021.22.40.90.70.7-1.2 LRRSurgery typeTM without RTRefBCT1.30.11.01.71.00.70.7-1.2TM with RT0.40.020.20.90.80.10.6-1.1Subsets IPW adjusted models for factors associated with LRRBCT vs. TM without RTStage I & HR+/HER2-No. of patientsTM without RT/BCTRRP95% CIStage I & HER2+1469/29451.00.90.8-1.3Stage I & TNBC199/2850.70.30.3-1.5Stage II & HR+/HER2-128/3170.4&lt;0.0010.3-0.6Stage II & HER2+690/7451.10.70.7-1.8Stage II & TNBC102/1080.90.50.5-1.4Stage I & HR+/HER2-110/1570.50.0480.3-0.99HER2 – human epidermal growth factor receptor 2; HR – hormone receptor; TNBC – triple negative breast cancer

Citation Format: Min Yi, Mariana Chavez Mac Gregor, Benjamin Smith, Abigail S Caudle, Sarah M DeSnyder, Henry M Kuerer, Kelly K Hunt. Comparing survival differences between breast-conserving therapy and mastectomy in patients with early-stage breast cancer undergoing upfront surgery [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-17.

Breast conservation and axillary management after primary systemic therapy in patients with early-stage breast cancer: the Lucerne toolbox

Primary systemic therapy is increasingly used in the treatment of patients with early-stage breast cancer, but few guidelines specifically address optimal locoregional therapies. Therefore, we established an international consortium to discuss clinical evidence and to provide expert advice on technical management of patients with early-stage breast cancer. The steering committee prepared six working packages to address all major clinical questions from diagnosis to surgery. During a consensus meeting that included members from European scientific oncology societies, clinical trial groups, and patient advocates, statements were discussed and voted on. A consensus was reached in 42% of statements, a majority in 38%, and no decision in 21%. Based on these findings, the panel developed clinical guidance recommendations and a toolbox to overcome many clinical and technical requirements associated with the diagnosis, response assessment, surgical planning, and surgery of patients with early-stage breast cancer. This guidance could convince clinicians and patients of the major clinical advancements purported by primary systemic therapy, the use of less extensive and more targeted surgery to improve the lives of patients with breast cancer.

Prospective Registry Trial Assessing the Use of Magnetic Seeds to Locate Clipped Nodes After Neoadjuvant Chemotherapy for Breast Cancer Patients

BACKGROUND

Targeted axillary dissection (TAD) involves locating and removing both clipped nodes and sentinel nodes for assessment of the axillary response to neoadjuvant chemotherapy (NAC) by clinically node-positive breast cancer patients. Initial reports described radioactive seeds used for localization, which makes the technique difficult to implement in some settings. This trial was performed to determine whether magnetic seeds can be used to locate clipped axillary lymph nodes for removal.

METHODS

This prospective registry trial enrolled patients who had biopsy-proven node-positive disease with a clip placed in the node and treatment with NAC. A magnetic seed was placed under ultrasound guidance in the clipped node after NAC. All the patients underwent TAD.

RESULTS

Magnetic seeds were placed in 50 patients by 17 breast radiologists. All the patients had successful seed placement at the first attempt (mean time for localization was 6.1 min; range 1-30 min). The final position of the magnetic seed was within the node (n = 44, 88%), in the cortex (n = 3, 6%), less than 3 mm from the node (n = 2, 4%), or by the clip when the node could not be adequately visualized (n = 1, 2%). The magnetic seed was retrieved at surgery from all the patients. In 49 (98%) of the 50 cases, the clip and magnetic seed were retrieved from the same node. Surgeons rated the transcutaneous and intraoperative localization as easy for 43 (86%) of the 50 cases. No device-related adverse events occurred.

CONCLUSIONS

Localization and selective removal of clipped nodes can be accomplished safely and effectively using magnetic seeds.

Anatomy and physiology of the sentinel lymph nodes of the upper extremity: Implications for axillary reverse mapping in breast cancer

BACKGROUND

This study characterizes the physiological drainage of the normal upper extremity using single-photon emission computed tomography/computed tomography (SPECT/CT) lymphoscintigraphy axillary reverse lymphatic mapping (ARM).

METHODS

A consecutive series of patients assessed with SPECT/CT lymphoscintigraphy ARM of the upper extremity were included. Anatomical localization of the axillary sentinel lymph nodes (SLN) was completed in normal axillae in relation to consistent anatomic landmarks. Retrospective case note analysis was performed to collect patient demographic data.

RESULTS

A total of 169 patients underwent SPECT/CT lymphoscintigraphy, and imaging of 182 normal axillae was obtained. All patients (100%) had an axillary SLN identified: 19% had a single contrast-enhanced SLN in the axilla and the remainder had multiple. The SLN(s) of the upper extremity was located in the upper outer quadrant (UOQ) of the axilla in 97% of cases (177 axillae). When the SLN(s) was found in the UOQ of the axilla, second-tier lymph nodes were found predominantly in the upper inner quadrant (50% of cases).

CONCLUSIONS

The upper extremity SLN(s) is located in a constant region of the axilla. This study provides the most complete investigation to date and results can be directly applied clinically to ARM techniques and adjuvant radiation planning.

Accuracy of Post-Neoadjuvant Chemotherapy Image-Guided Breast Biopsy to Predict Residual Cancer

Importance

Image-guided breast biopsy of a residual imaging abnormality or tumor bed after neoadjuvant chemotherapy (NACT) is increasingly used to assess residual cancer, facilitate risk-adaptive surgery, and potentially identify exceptional responders in whom local therapy may be de-escalated.

Objective

To further assess the accuracy of post-NACT image-guided biopsy to predict residual cancer in the breast.

Design, Setting, and Participants

This diagnostic study analyzed multicenter patient-level data of patients with breast cancer who were treated with NACT and underwent image-guided biopsy before surgery at Royal Marsden Hospital in London, UK; Seoul National University Hospital in Seoul, South Korea; and MD Anderson Cancer Center in Houston, Texas. Data were analyzed from June to July 2019.

Main Outcomes and Measures

Diagnostic accuracy of post-NACT image-guided biopsy. Final surgical pathology was used as reference standard.

Results

Data from 166 women were analyzed. The median (range) age was 49 (25-76) years. The median (range) tumor size on pretreatment and posttreatment imaging was 33.5 (12-100) mm and 10 (0-100) mm, respectively. The overall pathologic complete response rate was 51.2% (n = 85) (16.1% [5 of 31] for hormone receptor-positive/ERBB2 (formerly HER2)-negative; 44.7% [21 of 47] for hormone receptor-positive/ERBB2-positive; 69% [20 of 29] for hormone receptor-negative/ERBB2-positive; and 66.1% [39 of 59] for triple negative). The majority (143 [86.1%]) underwent image-guided vacuum-assisted biopsy (VAB), and 23 had core-cut biopsy. The median (range) needle gauge was 10 (7-14), and the median (range) number of samples was 6 (2-18). When image-guided biopsy (VAB and core-cut biopsy) was representative (159 [95.8%]), the false-negative rate across the whole cohort was 18.7% (95% CI, 10.6%-29.3%). Subgroup analysis of patients with a complete/partial clinical response and residual imaging abnormality of 2 cm or smaller with at least 6 VABs taken (76 [45.8%]) demonstrated a false-negative rate of 3.2% (95% CI, 0.1%-16.7%), a negative predictive value of 97.4% (95% CI, 86.5%-99.9%), and an overall accuracy of 89.5% (95% CI, 80.3%-95.3%).

Conclusions and Relevance

This large multicenter pooled data analysis suggests that a standardized protocol using image-guided VAB of a tumor bed measuring 2 cm or smaller with 6 or more representative samples allows reliable prediction of residual disease. These results could inform the design of de-escalation trials in NACT exceptional responders testing the safety of eliminating surgery.

Identification of breast cancer patients with pathologic complete response in the breast after neoadjuvant systemic treatment by an intelligent vacuum-assisted biopsy

BACKGROUND

Neoadjuvant systemic treatment elicits a pathologic complete response (pCR) in about 35% of women with breast cancer. In such cases, breast surgery may be considered overtreatment. We evaluated multivariate algorithms using patient, tumor, and vacuum-assisted biopsy (VAB) variables to identify patients with breast pCR.

METHODS

We developed and tested four multivariate algorithms: a logistic regression with elastic net penalty, an Extreme Gradient Boosting (XGBoost) tree, Support Vector Machines (SVM), and neural network. We used data from 457 women, randomly partitioned into training and test set (2:1), enrolled in three trials with stage 1-3 breast cancer, undergoing VAB before surgery. False-negative rate (FNR) and specificity were the main outcome measures. The best performing algorithm was validated in an independent fourth trial.

RESULTS

In the test set (n = 152), the logistic regression with elastic net penalty, XGboost tree, SVM, and neural network revealed an FNR of 1.2% (1 of 85 patients with missed residual cancer). Specificity of the logistic regression with elastic net penalty was 52.2% (35 of 67 women with surgically confirmed breast pCR identified), of the XGBoost tree 55.2% (37 of 67), of SVM 62.7% (42 of 67), and of the neural network 67.2% (45 of 67). External validation (n = 50) of the neural network showed an FNR of 0% (0 of 27) and a specificity of 65.2% (15 of 23). Area under the ROC curve for the neural network was 0.97 (95% CI, 0.94-1.00).

CONCLUSION

A multivariate algorithm can accurately select breast cancer patients without residual cancer after neoadjuvant treatment.

Effectiveness and Safety of Magseed-localization for Excision of Breast Lesions: A Prospective, Phase IV Trial

OBJECTIVE

A prospective, phase IV study was conducted to assess the effectiveness of Magseed to localize breast lesions requiring surgical excision.

BACKGROUND

Since FDA approval in 2016, Magseed has been increasingly used to localize non-palpable lesions due to advantages over wires or radioactive seeds. This is the first prospective, post marketing trial of Magseed.

METHODS

From 1/2017-2/2018, 107 women with lesions requiring localization were enrolled at a single institution. Primary endpoint was Magseed retrieval rate. Secondary endpoints were adverse events, accuracy of placement, surgery duration and positive margin rate. Clinicians were surveyed for ease of use using a Likert scale. Descriptive statistics and Fisher's exact test were performed to assess univariable associations with positive margins.

RESULTS

There were 124 Magseeds placed including one marker in 93 subjects, 2 markers in 11 and 3 markers in 3. The majority of lesions were masses (63%) followed by calcifications (24%). All 124 Magseeds were placed within 10mm of the target lesion and surgically retrieved with median operative time of 15min (range 4-47). No device-related adverse events occurred. Of the 98 malignant lesions, 9 had positive margins and 7 of them underwent a second surgery for additional margins. On univariable analysis, age ≤ 50 (25.0% vs 6.4%, p=0.04), lesion histology (p = 0.03), and pathologic T-stage (p = 0.04) were significantly associated with positive margins. Clinicians rated the Magseed very or fairly easy to use in most cases.

CONCLUSIONS

The Magseed system for localization of non-palpable lesions was effective and safe; all markers were successfully retrieved with margin-negative resections in 91%. This study supports use of Magseed for localization of breast lesions.

Factors Associated with Pathological Node Negativity in Inflammatory Breast Cancer: Are There Patients Who May be Candidates for a De-Escalation of Axillary Surgery?

BACKGROUND

Modified radical mastectomy (MRM), which includes axillary dissection, is the standard of care for inflammatory breast cancer (IBC). While more limited axillary staging after neoadjuvant chemotherapy (NAC) in clinically node-positive non-IBC has been increasingly adopted, the impact of these techniques in IBC is not clear. To inform patient selection for further study of limited axillary surgery, we aimed to describe the frequency and factors associated with pathological node-negativity (ypN0) in IBC.

METHODS

Patients with IBC who received NAC and MRM were identified from a prospective institutional database (2004-2019). Binary logistic regression analyses were conducted to identify factors associated with ypN0.

RESULTS

Of 453 patients, 189 (41.7%) had a post-NAC clinical nodal stage (ycN stage) of N0 (ycN1: 150, 33.1%; ycN2: 4, 0.9%; ycN3: 47, 10.4%; unknown: 63, 13.9%); 156 (34%) were ypN0. On multivariable analysis, higher tumor grade was not associated with ypN0 (odds ratio [OR] 1.59, 95% confidence interval [CI] 0.90-2.81, p =0.11). Compared with hormone receptor (HR)-negative/human epidermal growth factor receptor 2 (HER2)-negative tumors (n =113, 24.9%), HR-positive/HER2-negative tumors (n =169, 37.3%) had a trend toward less ypN0 (OR 0.55, 95% CI 0.29-1.02, p =0.06); HR-positive/HER2-positive tumors (n =79, 17.4%) were similar to HR-negative/HER2-negative tumors (OR 0.72, 95% CI 0.35-1.48, p =0.37); and HR-negative/HER2-positive tumors (n =92, 20.3%) were associated with increased ypN0 (OR 4.82, 95% CI 2.41-9.63, p <0.001). As ycN stage increased, the likelihood of ypN0 decreased compared with ycN0 patients (ycN1/2: OR 0.54, 95% CI 0.32-0.89, p =0.02; ycN3: OR 0.29, 95% CI 0.13-0.67, p =0.004).

CONCLUSIONS

One-third of patients with IBC who received NAC and MRM had pathologically negative nodes. Factors associated with ypN0 included ycN0 status and HR-negative/HER2-positive subtype. Large, prospective studies are needed to investigate the feasibility of alternative nodal evaluation strategies in IBC, with consideration to these subgroups.

Factors Associated With Lymphedema in Women With Node-Positive Breast Cancer Treated With Neoadjuvant Chemotherapy and Axillary Dissection

Importance

Most lymphedema studies include a heterogeneous population and focus on patients treated with adjuvant chemotherapy.

Objective

To examine factors associated with lymphedema after neoadjuvant chemotherapy (NAC) and axillary lymph node dissection in women with node-positive breast cancer.

Design, Setting, and Participants

This cohort study included data from 701 women 18 years or older with cT0-T4N1-2M0 breast cancer with documented axillary nodal metastasis at diagnosis who were enrolled in the American College of Surgeons Oncology Group Z1071 (Alliance for Clinical Trials in Oncology) trial, which took place from January 1, 2009, to December 31, 2012. Data analysis was performed from January 11, 2018, to November 9, 2018.

Interventions

All participants received NAC, breast operation, and axillary lymph node dissection. Participants underwent prospective arm measurements and symptom assessment after NAC completion and at 6-month intervals to 36 months postoperatively.

Main Outcomes and Measures

Factors associated with lymphedema were defined as self-reported arm heaviness or swelling (lymphedema symptoms) or an arm volume increase of 10% or more (V10) or 20% or more (V20).

Results

A total of 486 patients (mean [SD] age, 50.1 [10.8] years) were included in this study. Median follow-up for the 3 measures was 2.2 to 3.0 years. Cumulative lymphedema incidence at 3 years was 37.8% (95% CI, 33.1%-43.2%) for lymphedema symptoms, 58.4% (95% CI, 53.2%-64.1%) for V10, and 36.9% (95% CI, 31.9%-42.6%) for V20. Increasing body mass index (hazard ratio [HR], 1.04; 95% CI, 1.01-1.06) and NAC for 144 days or longer (HR, 1.48; 95% CI, 1.01-2.17) were associated with lymphedema symptoms. The V20 incidence was higher among patients who received NAC for 144 days or longer (HR, 1.79; 95% CI, 1.19-2.68). The V10 incidence was highest in patients with 30 nodes or more removed (HR, 1.70; 95% CI, 1.15-2.52) and increased with number of positive nodes (HR, 1.03; 95% CI, 1.00-1.06). On multivariable analysis, obesity was significantly associated with lymphedema symptoms (HR, 1.03; 95% CI, 1.01-1.06), and NAC length was significantly associated with V20 (HR, 1.74; 95% CI, 1.15-2.62).

Conclusions and Relevance

In this study, longer NAC duration and obesity were associated with increased lymphedema incidence, suggesting that patients in these groups may benefit from enhanced prospective lymphedema surveillance.

Hepatic resection for breast cancer liver metastases: Impact of intrinsic subtypes

INTRODUCTION

The role of surgery for breast cancer liver metastases (BCLM) remains controversial. This study aimed to analyze survival in patients treated with hepatectomy plus systemic therapy or systemic therapy alone for BCLM and to determine selection factors to guide surgical therapy.

MATERIALS AND METHODS

Patients who underwent hepatectomy plus systemic therapy (n = 136) and systemic therapy alone for isolated BCLM (n = 763) were compared. Overall survival (OS) was analyzed after propensity score matching. Intrinsic subtypes were defined as: luminal A (estrogen receptor [ER]+ and/or progesterone receptor positive [PR]+, human epidermal growth factor receptor 2 [HER2]-), luminal B (ER and/or PR+, HER2+), HER2-enriched (ER and PR-, HER2+), and basal-like (ER, PR, HER2-).

RESULTS

After hepatectomy, independent predictors of poor OS were number and size of liver metastases, and intrinsic subtype (hazard ratios, 1.11, 1.16, and 4.28, respectively). Median OS was 75 and 81 months among patients with luminal B and HER2-enriched subtypes, compared with 17 and 53 months among patients with basal-like and luminal A subtypes (P < .001). Median progression-free survival (PFS) was 60 months with the HER2-enriched subtype, compared with 17, 16, and 5 months with luminal A, luminal B, and basal-like subtypes, respectively (P < .001). After propensity score matching, 5-year OS rates were 56% vs. 40% in the surgery vs. systemic therapy alone groups (P = .018).

CONCLUSION

Surgical resection of BCLM yielded higher OS compared with systemic therapy alone and prolonged PFS among patients with the HER2-enriched subtype. These findings support the use of surgical therapy in appropriately selected patients, based on intrinsic subtypes.

Effectiveness of Breast-Conserving Surgery and 3-Dimensional Conformal Partial Breast Reirradiation for Recurrence of Breast Cancer in the Ipsilateral Breast: The NRG Oncology/RTOG 1014 Phase 2 Clinical Trial

Importance

Mastectomy is standard for recurrence of breast cancer after breast conservation therapy with whole breast irradiation. The emergence of partial breast irradiation led to consideration of its application for reirradiation after a second lumpectomy for treatment of recurrence of breast cancer in the ipsilateral breast.

Objectives

To assess the effectiveness and adverse effects of partial breast reirradiation after a second lumpectomy and whether the treatment is an acceptable alternative to mastectomy.

Design, Setting, and Participants

The NRG Oncology/Radiation Therapy Oncology Group 1014 trial is a phase 2, single-arm, prospective clinical trial of 3-dimensional, conformal, external beam partial breast reirradiation after a second lumpectomy for recurrence of breast cancer in the ipsilateral breast after previous whole breast irradiation. The study opened on June 4, 2010, and closed June 18, 2013. Median follow-up was 5.5 years. This analysis used all data received at NRG Oncology through November 18, 2018. Eligible patients experienced a recurrence of breast tumor that was less than 3 cm and unifocal in the ipsilateral breast more than 1 year after breast-conserving therapy with whole breast irradiation and who had undergone excision with negative margins.

Interventions

Adjuvant partial breast reirradiation, 1.5 Gy twice daily for 30 treatments during 15 days (45 Gy), using a 3-dimensional conformal technique.

Main Outcomes and Measures

The main outcomes of the present study were the predefined secondary study objectives of recurrence of breast cancer in the ipsilateral breast, late adverse events (>1 year after treatment), mastectomy incidence, distant metastasis-free survival, overall survival, and circulating tumor cell incidence.

Results

A total of 65 women were enrolled, with 58 evaluable for analysis (mean [SD] age, 65.12 [9.95] years; 48 [83%] white). Of the recurrences of breast cancer in the ipsilateral breast, 23 (40%) were noninvasive and 35 (60%) were invasive. In all 58 patients, 53 (91%) had tumors 2 cm or smaller. All tumors were clinically node negative. A total of 44 patients (76%) tested positive for estrogen receptor, 33 (57%) for progesterone receptor, and 10 (17%) for ERBB2 (formerly HER2 or HER2/neu) overexpression. Four patients had breast cancer recurrence, with a 5-year cumulative incidence of 5% (95% CI, 1%-13%). Seven patients underwent ipsilateral mastectomies for a 5-year cumulative incidence of 10% (95% CI, 4%-20%). Both distant metastasis-free survival and overall survival rates were 95% (95% CI, 85%-98%). Four patients (7%) had grade 3 and none had grade 4 or higher late treatment adverse events.

Conclusions and Relevance

For patients experiencing recurrence of breast cancer in the ipsilateral breast after lumpectomy and whole breast irradiation, a second breast conservation was achievable in 90%, with a low risk of re-recurrence of cancer in the ipsilateral breast using adjuvant partial breast reirradiation. This finding suggests that this treatment approach is an effective alternative to mastectomy.

Long-term primary results of accelerated partial breast irradiation after breast-conserving surgery for early-stage breast cancer: a randomised, phase 3, equivalence trial

BACKGROUND

Whole-breast irradiation after breast-conserving surgery for patients with early-stage breast cancer decreases ipsilateral breast-tumour recurrence (IBTR), yielding comparable results to mastectomy. It is unknown whether accelerated partial breast irradiation (APBI) to only the tumour-bearing quadrant, which shortens treatment duration, is equally effective. In our trial, we investigated whether APBI provides equivalent local tumour control after lumpectomy compared with whole-breast irradiation.

METHODS

We did this randomised, phase 3, equivalence trial (NSABP B-39/RTOG 0413) in 154 clinical centres in the USA, Canada, Ireland, and Israel. Adult women (>18 years) with early-stage (0, I, or II; no evidence of distant metastases, but up to three axillary nodes could be positive) breast cancer (tumour size ≤3 cm; including all histologies and multifocal breast cancers), who had had lumpectomy with negative (ie, no detectable cancer cells) surgical margins, were randomly assigned (1:1) using a biased-coin-based minimisation algorithm to receive either whole-breast irradiation (whole-breast irradiation group) or APBI (APBI group). Whole-breast irradiation was delivered in 25 daily fractions of 50 Gy over 5 weeks, with or without a supplemental boost to the tumour bed, and APBI was delivered as 34 Gy of brachytherapy or 38·5 Gy of external bream radiation therapy in 10 fractions, over 5 treatment days within an 8-day period. Randomisation was stratified by disease stage, menopausal status, hormone-receptor status, and intention to receive chemotherapy. Patients, investigators, and statisticians could not be masked to treatment allocation. The primary outcome of invasive and non-invasive IBTR as a first recurrence was analysed in the intention-to-treat population, excluding those patients who were lost to follow-up, with an equivalency test on the basis of a 50% margin increase in the hazard ratio (90% CI for the observed HR between 0·667 and 1·5 for equivalence) and a Cox proportional hazard model. Survival was assessed by intention to treat, and sensitivity analyses were done in the per-protocol population. This trial is registered with ClinicalTrials.gov, NCT00103181.

FINDINGS

Between March 21, 2005, and April 16, 2013, 4216 women were enrolled. 2109 were assigned to the whole-breast irradiation group and 2107 were assigned to the APBI group. 70 patients from the whole-breast irradiation group and 14 from the APBI group withdrew consent or were lost to follow-up at this stage, so 2039 and 2093 patients respectively were available for survival analysis. Further, three and four patients respectively were lost to clinical follow-up (ie, survival status was assessed by phone but no physical examination was done), leaving 2036 patients in the whole-breast irradiation group and 2089 in the APBI group evaluable for the primary outcome. At a median follow-up of 10·2 years (IQR 7·5-11·5), 90 (4%) of 2089 women eligible for the primary outcome in the APBI group and 71 (3%) of 2036 women in the whole-breast irradiation group had an IBTR (HR 1·22, 90% CI 0·94-1·58). The 10-year cumulative incidence of IBTR was 4·6% (95% CI 3·7-5·7) in the APBI group versus 3·9% (3·1-5·0) in the whole-breast irradiation group. 44 (2%) of 2039 patients in the whole-breast irradiation group and 49 (2%) of 2093 patients in the APBI group died from recurring breast cancer. There were no treatment-related deaths. Second cancers and treatment-related toxicities were similar between the two groups. 2020 patients in the whole-breast irradiation group and 2089 in APBI group had available data on adverse events. The highest toxicity grade reported was: grade 1 in 845 (40%), grade 2 in 921 (44%), and grade 3 in 201 (10%) patients in the APBI group, compared with grade 1 in 626 (31%), grade 2 in 1193 (59%), and grade 3 in 143 (7%) in the whole-breast irradiation group.

INTERPRETATION

APBI did not meet the criteria for equivalence to whole-breast irradiation in controlling IBTR for breast-conserving therapy. Our trial had broad eligibility criteria, leading to a large, heterogeneous pool of patients and sufficient power to detect treatment equivalence, but was not designed to test equivalence in patient subgroups or outcomes from different APBI techniques. For patients with early-stage breast cancer, our findings support whole-breast irradiation following lumpectomy; however, with an absolute difference of less than 1% in the 10-year cumulative incidence of IBTR, APBI might be an acceptable alternative for some women.

FUNDING

National Cancer Institute, US Department of Health and Human Services.

Association of Low Nodal Positivity Rate Among Patients With ERBB2-Positive or Triple-Negative Breast Cancer and Breast Pathologic Complete Response to Neoadjuvant Chemotherapy

Importance

A recent publication reported that of 527 patients with clinically node-negative (cN0) cT1/cT2 triple-negative breast cancer (TNBC) or ERBB2-positive disease treated with neoadjuvant chemotherapy (NAC), 100% of those who achieved a breast pathologic complete response (pCR) had pathologic node negativity (pN0). Eliminating axillary surgery in these patients has been suggested as safe based on these results.

Objective

To evaluate nodal positivity rates in patients with cT1/cT2 N0 ERBB2-positive disease and TNBC with a breast pCR after NAC using the National Cancer Database (NCDB), which included academic and community settings.

Design, Setting, and Participants

This retrospective study reviewed data from the NCDB from January 1, 2010, through December 31, 2015. Participants included patients with cN0/cN1 cT1/cT2 breast cancer who received NAC followed by surgery. Pathologic nodal positivity rates by breast pCR were compared in cN0 and cN1 disease, within each tumor subtype (ERBB2-positive, TNBC, and hormone receptor-positive/ERBB2-negative). Data were analyzed from September 13, 2017, through January 30, 2018.

Exposures

Neoadjuvant chemotherapy followed by surgery.

Main Outcomes and Measures

The pathologic nodal positivity rate after NAC (ypN) specifically in patients with cT1/cT2 cN0 ERBB2-positive disease or TNBC who achieve a breast pCR after NAC.

Results

A total of 30 821 patients with cT1/cT2 cN0/cN1 breast cancer treated with NAC and surgical resection (99.6% female; mean [SD] age, 52.0 [11.5] years) were identified. Of 6802 patients with cN0 ERBB2-positive disease, 3062 (45.0%) achieved breast pCR and of those, 49 (1.6%; 95% CI, 1.2%-2.1%) were ypN positive. In 6222 patients with cN0 TNBC, 2315 (37.2%) achieved breast pCR, and of those, 36 (1.6%; 95% CI, 1.1%-2.1%) were pathologic node positive after NAC. Rates of ypN positivity were higher in patients with cN0 and residual disease in the breast; 632 of 3740 (16.9%) with ERBB2-positive disease and 492 of 3907 (12.6%) with TNBC with residual disease in the breast were node positive (P < .001). Among 4164 patients with cN1 ERBB2-positive disease, 1801 (43.3%) achieved breast pCR, with 223 of those (12.4%) being ypN positive. In 3293 patients with TNBC, 1229 (37.3%) achieved breast pCR, with 173 of these (14.1%) being ypN postive. Breast pCR rates were lower in hormone receptor-positive/ERBB2-negative disease (646 of 5069 [12.7%] for cN0; 711 of 5271 [13.5%] for cN1) and ypN positivity rates were 26 of 646 (4.0%) in cN0 vs 217 of 711 (30.5%) in cN1 disease with breast pCR and 1464 of 4423 (33.1%) in cN0 disease vs 3775 of 4560 (82.8%) in cN1 disease with residual disease in the breast.

Conclusions and Relevance

In this study, the highest rates of breast pCR were seen in ERBB2-positive disease and TNBC. In patients with cN0 ERBB2-positive disease or TNBC with breast pCR, the nodal positivity rate was less than 2%, which supports consideration of omission of axillary surgery in this subset of patients.

Consensus Guidelines on Genetic` Testing for Hereditary Breast Cancer from the American Society of Breast Surgeons

BACKGROUND

The purpose of this consensus guideline is to outline recommendations for genetic testing that medical professionals can use to assess hereditary risk for breast cancer.

METHODS

Literature review included large datasets, basic and clinical science publications, and recent updated national guidelines. Genetic testing to assess hereditary risk of cancer is a complex, broad, and dynamic area of medical research. The dominant focus of this guideline is limited in scope to breast cancer.

RESULTS

There is a lack of consensus among experts regarding which genes among many should be tested in different clinical scenarios. There is also variation in the degree of consensus regarding the understanding of risk and appropriate clinical management of mutations in many genes.

CONCLUSIONS

Genetic testing should be made available to all patients with a personal history of breast cancer. Recent data are reviewed that support genetic testing being offered to each patient with breast cancer (newly diagnosed or with a personal history). If genetic testing is performed, such testing should include BRCA1/BRCA2 and PALB2, with other genes as appropriate for the clinical scenario and family history. For patients with newly diagnosed breast cancer, identification of a mutation may impact local treatment recommendations. Patients who had genetic testing previously may benefit from updated testing. Genetic testing should be made available to patients without a history of breast cancer who meet National Comprehensive Cancer Network guidelines. Finally, variants of uncertain significance are not clinically actionable and these patients should be managed based on their individual risk factors.