Primary Systemic Treatment in the Management of Operable Breast Cancer: Best Surgical Approach for Diagnosis, Biological Evaluation, and Research

Determining individual suitability for neoadjuvant systemic therapy in breast cancer patients through deep learning

BACKGROUND

The survival advantage of neoadjuvant systemic therapy (NST) for breast cancer patients remains controversial, especially when considering the heterogeneous characteristics of individual patients.

OBJECTIVE

To discern the variability in responses to breast cancer treatment at the individual level and propose personalized treatment recommendations utilizing deep learning (DL).

METHODS

Six models were developed to offer individualized treatment suggestions. Outcomes for patients whose actual treatments aligned with model recommendations were compared to those whose did not. The influence of certain baseline features of patients on NST selection was visualized and quantified by multivariate logistic regression and Poisson regression analyses.

RESULTS

Our study included 94,487 female breast cancer patients. The Balanced Individual Treatment Effect for Survival data (BITES) model outperformed other models in performance, showing a statistically significant protective effect with inverse probability treatment weighting (IPTW)-adjusted baseline features [IPTW-adjusted hazard ratio: 0.51, 95% confidence interval (CI), 0.41-0.64; IPTW-adjusted risk difference: 21.46, 95% CI 18.90-24.01; IPTW-adjusted difference in restricted mean survival time: 21.51, 95% CI 19.37-23.80]. Adherence to BITES recommendations is associated with reduced breast cancer mortality and fewer adverse effects. BITES suggests that patients with TNM stage IIB, IIIB, triple-negative subtype, a higher number of positive axillary lymph nodes, and larger tumors are most likely to benefit from NST.

CONCLUSIONS

Our results demonstrated the potential of BITES to aid in clinical treatment decisions and offer quantitative treatment insights. In our further research, these models should be validated in clinical settings and additional patient features as well as outcome measures should be studied in depth.

Radiological characteristics of invasive micropapillary carcinoma of the breast

AIM

To analyse the various imaging features of invasive micropapillary carcinoma (IMPC), a distinct variant of breast cancer, by mammography, ultrasound, and contrast-enhanced mammography.

MATERIALS AND METHODS

This study included 68 female patients with histopathologically proven invasive micropapillary carcinoma who underwent mammography, ultrasound, and contrast-enhanced mammography examinations. The findings encountered by each imaging tool were analysed using the Breast Imaging Reporting and Data System (BI-RADS) lexicon.

RESULTS

In this retrospective study, 64.7% of cases were of the pure form of IMPC. Most of the cases showed an aggressive clinical course, with lymphovascular invasion noted in 76.5% of cases, while 60.3% of cases showed associated pathological lymphadenopathy. The N3 stage was reported in 25% of cases. On analysing the mammographic and ultrasound imaging findings, a significant association between irregular shape and a non-circumscribed margin with IMPC was found. Associated calcification was noted in 47% of cases. Pathological enhancement of moderate or marked conspicuity was noted in cases that underwent contrast-enhanced mammography, with the most commonly encountered finding being enhancing irregular and non-circumscribed masses.

CONCLUSION

The mammographic and ultrasound imaging features of IMPC are indistinguishable from other aggressive types of breast cancer. At contrast-enhanced mammography examination, pathological enhancement of moderate to marked conspicuity was shown in all cases. The observed strong association of IMPC with lymphovascular invasion and lymph node metastasis with higher nodal stage in this study mandate meticulous sonographic examination of the axilla, as well as the infra, and supraclavicular regions if pathological axillary lymphadenopathy was noted.

Successful Breast Conservation After Neoadjuvant Chemotherapy in Lobular Breast Cancer: The Role of Menopausal Status in Response to Treatment

BACKGROUND

While neoadjuvant chemotherapy (NAC) has been shown to increase rates of breast conservation surgery (BCS) for breast cancer, response rates in invasive lobular carcinoma (ILC) appear lower than other histologic subtypes. Some data suggest higher response rates to NAC in premenopausal versus postmenopausal patients, but this has not been studied in ILC. We evaluated the rates of successful BCS after NAC in patients with ILC stratified by menopausal status.

PATIENTS AND METHODS

We analyzed data from a single-institution cohort of 666 patients with stage I-III hormone receptor positive HER-2 negative ILC. We used t-tests, chi-squared tests, and multivariable logistic regression to investigate rates of NAC use, attempted BCS, and associations between NAC and successful BCS by menopausal status.

RESULTS

In 217 premenopausal and 449 postmenopausal patients, NAC was used more often in the premenopausal group (15.2% vs. 9.8%, respectively, p = 0.041). Among those who attempted breast conservation (51.3% of pre- and 64.8% of postmenopausal cohorts), NAC was not associated with successful BCS in either group. Interestingly, for postmenopausal patients, receipt of NAC was significantly associated with increased rates of completion mastectomy in those who had positive margins at the first attempt at BCS.

CONCLUSION

NAC was not associated with successful BCS in either premenopausal or postmenopausal patients with ILC. Although premenopausal patients were more likely to receive NAC, these data suggest that menopausal status may not be a good predictor of response to chemotherapy. Better predictors of response and more efficacious treatment for patients with ILC are needed.

A prospective cohort study identifying radiologic and tumor related factors of importance for breast conserving surgery after neoadjuvant chemotherapy

INTRODUCTION

Neoadjuvant chemotherapy (NAC) is an established treatment option for early breast cancer, potentially downstaging the tumor and increasing the eligibility for breast-conserving surgery (BCS). The primary aim of this study was to assess the rate of BCS after NAC, and the secondary aim was to identify predictors of application of BCS after NAC.

MATERIALS AND METHODS

This was an observational prospective cohort study of 226 patients in the SCAN-B (Clinical Trials NCT02306096) neoadjuvant cohort during 2014-2019. Eligibility for BCS was assessed at baseline and after NAC. Uni- and multivariable logistic regression analyses were performed using covariates with clinical relevance and/or those associated with outcome (BCS versus mastectomy), including tumor subtype, by gene expression analysis.

RESULTS

The overall BCS rate was 52%, and this rate increased during the study period (from 37% to 52%). Pathological complete response was achieved in 69 patients (30%). Predictors for BCS were smaller tumor size on mammography, visibility on ultrasound, histological subtype other than lobular, benign axillary status, and a diagnosis of triple-negative or HER2-positive subtype, with a similar trend for gene expression subtypes. Mammographic density was negatively related to BCS in a dose-response pattern. In the multivariable logistic regression model, tumor stage at diagnosis and mammographic density showed the strongest association with BCS.

CONCLUSION

The rate of BCS after NAC increased during the study period to 52%. With modern treatment options for NAC the potential for tumor response and BCS eligibility might further increase.

Survival Outcomes After Breast-Conserving Therapy Compared With Mastectomy for Patients With Early-Stage Invasive Micropapillary Carcinoma of the Breast: A SEER Population-Based Study

Background

Invasive micropapillary breast carcinoma (IMPC) is a relatively rare pathological type of invasive breast cancer. Little is currently known on the efficacy and safety of breast-conserving treatment (BCT, lumpectomy plus postsurgical radiation) compared with mastectomy in women diagnosed with early-stage IMPC. Accordingly, we sought to investigate the long-term prognostic differences between BCT and mastectomy in patients with T1-3N0-3M0 invasive micropapillary breast carcinoma using data from the Surveillance, Epidemiology, and End Results (SEER) database.

Materials and Methods

We retrospectively analyzed 1,203 female patients diagnosed with early-stage IMPC between 2004 and 2015 from the SEER database. The impact of different surgical approaches on patient prognosis was assessed by the Kaplan-Meier method and Cox proportional risk models.

Results

A total of 609 and 594 patients underwent mastectomy and BCT, respectively. Compared with patients who underwent a mastectomy, patients in the BCT group were older and had lower tumor diameters, lower rates of lymph nodes metastasis, and higher rates of ER receptor positivity and PR receptor positivity (p < 0.05). Kaplan-Meier plots showed that the overall survival (OS) and breast cancer-specific survival (BCSS) were higher in the BCT group than in the mastectomy group. In subgroup analysis, patients with T2 stage in the BCT group had better OS than the mastectomy group. Multivariate analysis showed no statistical difference in OS and BCSS for patients in the mastectomy group compared with the BCT group (hazard ratio (HR) = 0.727; 95% confidence interval (95% CI) 0.369–1.432, p = 0.357; HR = 0.762; 95% CI 0.302–1.923, p = 0.565; respectively). During the multivariate analysis and stratifying for the T stage, a better OS was found for patients with T2 stage in the BCT group than the mastectomy group (HR = 0.333, 95% CI: 0.149–0.741, p = 0.007). There was no significant difference in OS for patients with T1 and T3 stages between the BCT and mastectomy groups (p > 0.05).

Conclusion

In women with early-stage IMPC, BCT was at least equivalent to mastectomy in terms of survival outcomes. When both procedures are feasible, BCT should be recommended as the standard surgical treatment, especially for patients with T2 disease.

Surgical Treatment after Neoadjuvant Systemic Therapy in Young Women with Breast Cancer: Results from a Prospective Cohort Study

OBJECTIVE

We aimed to investigate eligibility for breast-conserving surgery (BCS) pre- and post-neoadjuvant systemic therapy (NST), and trends in the surgical treatment of young breast cancer patients.

BACKGROUND

Young women with breast cancer are more likely to present with larger tumors and aggressive phenotypes, and may benefit from NST. Little is known about how response to NAC influences surgical decisions in young women.

METHODS

The Young Women's Breast Cancer Study (YWS), a multicenter prospective cohort of women diagnosed with breast cancer at age ≤40, enrolled 1302 patients from 2006 to 2016. Disease characteristics, surgical recommendations, and reasons for choosing mastectomy among BCS-eligible patients were obtained through the medical record. Trends in use of NST, rate of clinical and pathologic complete response (cCR and pCR), and surgery were also assessed.

RESULTS

Of 1117 women with unilateral stage I-III breast cancer, 315 (28%) received NST. Pre-NST, 26% were BCS eligible, 17% were borderline eligible, and 55% were ineligible. After NST, BCS eligibility increased from 26% to 42% (p < 0.0001). Among BCS-eligible patients after NST (n = 133), 41% chose mastectomy with reasons being patient preference (53%), BRCA or TP53 mutation (35%) and family history (5%). From 2006 to 2016, the rates of NST (p = 0.0012), cCR (p < 0.0001) and bilateral mastectomy (p < 0.0001) increased, but the rate of BCS did not increase (p = 0.34).

CONCLUSION

While the proportion of young women eligible for BCS increased after NST, many patients choose mastectomy, suggesting that surgical decisions are often driven by factors beyond extent of disease and treatment response.

Breast Conservation After Neoadjuvant Chemotherapy for Triple-Negative Breast Cancer: Surgical Results From the BrighTNess Randomized Clinical Trial

Importance

Neoadjuvant systemic therapy (NST) is often administered to enable breast-conserving therapy (BCT) in stages II to III breast cancer.

Objectives

To prospectively evaluate the role of NST in conversion from BCT ineligibility to BCT eligibility and to assess the association of response to NST, germline BRCA (gBRCA) status, and region of treatment with surgical choice in women with triple-negative breast cancer (TNBC).

Design, Setting, and Participants

This prespecified secondary analysis of a multicentered, phase 3, double-blind, randomized clinical trial (BrighTNess) enrolled 634 eligible women across 145 centers in 15 countries in North America, Europe, and Asia. Women with operable, clinical stages II to III TNBC who underwent gBRCA mutation testing before initiating NST were eligible to participate. Data were collected from April 1, 2014, to December 8, 2016. This preplanned analysis was performed from January 5, 2018, to October 28, 2019.

Interventions

Study participants were randomized to receive 12 weeks of weekly paclitaxel alone or with the addition of carboplatin and/or veliparib, followed by 4 cycles of doxorubicin hydrochloride and cyclophosphamide.

Main Outcomes and Measures

Surgeons assessed BCT candidacy by clinical and radiographic criteria before and after NST. Surgical choices and whether BCT eligibility was associated with the likelihood of pathologic complete response were then analyzed.

Results

Among the 634 randomized patients (median age, 51 [range, 22-78] years), pre- and post-NST assessments were available for 604 patients. Of 141 patients deemed BCT ineligible at baseline, 75 (53.2%) converted to BCT eligible. Overall, 342 (68.1%) of 502 patients deemed BCT eligible after NST underwent BCT, including 42 (56.0%) of the 75 who converted to BCT eligible. Patients treated in Europe and Asia were more likely to undergo BCT (odds ratio, 2.66; 95% CI, 1.84-3.84) compared with those treated in North America. Among patients without gBRCA mutation undergoing mastectomy, those treated in North America were more likely to undergo contralateral prophylactic mastectomy (57 of 81 [70.4%] vs 6 of 30 [20.0%]; P < .001). Rates of pathologic complete response were similar between patients deemed BCT eligible at baseline and those who were BCT ineligible but converted to BCT eligibility after NST (55.3 [235 of 425] vs 49.3% [37 of 75]; P = .38).

Conclusions and Relevance

This prospective analysis of NST and BCT eligibility in TNBC demonstrates a conversion from BCT ineligibility to BCT eligibility of 53.2%. Lower BCT rates among eligible patients and higher bilateral mastectomy rates among patients without gBRCA mutation in North America merit investigation.

Trial Registration

ClinicalTrials.gov identifier: NCT02032277.

Pre-operative progesterone benefits operable breast cancer patients by modulating surgical stress

PURPOSE

We have reported a survival benefit of single injection of hydroxyprogesterone prior to surgery for primary tumour in patients with node-positive operable breast cancer. Hydroxyprogesterone was meant to recapitulate the luteal phase of menstrual cycle in these women. We wanted to understand the molecular basis of action of hydroxyprogesterone on primary breast tumours in a peri-operative setting.

METHODS

We performed whole transcriptome sequencing (RNA-Seq) of primary breast tumour samples collected from patients before and after hydroxyprogesterone exposure and controls. Paired breast cancer samples were obtained from patients who were given hydroxyprogesterone before surgery and a group of patients who were subjected to only surgery.

RESULTS

A test of significance between the two groups revealed 207 significantly altered genes, after correction for multiple hypothesis testing. We found significantly contrasting gene expression patterns in exposed versus unexposed groups; 142 genes were up-regulated post-surgery among exposed patients, and down-regulated post-surgery among unexposed patients. Significantly enriched pathways included genes that respond to progesterone, cellular stress, nonsense-mediated decay of proteins and negative regulation of inflammatory response. These results suggest that cellular stress is modulated by hydroxyprogesterone. Network analysis revealed that UBC, a mediator of stress response, to be a major node to which many of the significantly altered genes connect.

CONCLUSIONS

Our study suggests that pre-operative exposure to progesterone favourably modulates the effect of surgical stress, and this might underlie its beneficial effect when administered prior to surgery.

Axillary Management of Stage II/III Breast Cancer in Patients Treated with Neoadjuvant Systemic Therapy: Results of CALGB 40601 (HER2-Positive) and CALGB 40603 (Triple-Negative)

BACKGROUND

Management of the axilla in stage II/III breast cancer undergoing neoadjuvant systemic therapy (NST) is controversial. To understand current patterns of care, we collected axillary data from 2 NST trials: HER2-positive (Cancer and Leukemia Group B [CALGB] 40601) and triple-negative (CALGB 40603).

STUDY DESIGN

Axillary evaluation pre- and post-NST was per the treating surgeon and could include sentinel node biopsy. Post-NST, node-positive patients were recommended to undergo axillary lymph node dissection (ALND). We report pre-NST histopathologic nodal evaluation and post-NST axillary surgical procedures with correlation to clinical and pathologic nodal status.

RESULTS

Seven hundred and forty-two patients were treated, 704 had complete nodal data pre-NST and post-NST. Pre-NST, 422 (60%) of 704 patients underwent at least 1 procedure for axillary node evaluation (total of 468 procedures): fine needle aspiration (n = 234; 74% positive), core needle biopsy (n = 138; 72% positive), and sentinel node biopsy (n = 96; 33% positive). Pre-NST, 304 patients were considered node-positive. Post-NST, 304 of 704 patients (43%) underwent sentinel node biopsy; 44 were positive and 259 were negative (29 and 36 patients, respectively, had subsequent ALND). Three hundred and ninety-one (56%) patients went directly to post-NST ALND and 9 (1%) pre-NST node-positive patients had no post-NST axillary procedure. Post-NST, 170 (24%) of the 704 patients had residual axillary disease. Agreement between post-NST clinical and radiologic staging and post-NST histologic staging was strongest for node-negative (81%) and weaker for node-positive (N1 31%, N2 29%), with more than half of the clinically node-positive patients found to be pathologic negative (p < 0.001).

CONCLUSIONS

Our results suggest there is no widely accepted standard for axillary nodal evaluation pre-NST. Post-NST staging was highly concordant in patients with N0 disease, but poorly so in node-positive disease. Accurate methods are needed to identify post-NST patients without residual axillary disease to potentially spare ALND.

Impact of neoadjuvant therapy on eligibility for and frequency of breast conservation in stage II-III HER2-positive breast cancer: surgical results of CALGB 40601 (Alliance)

OBJECTIVE

It had been previously shown that patients who receive neoadjuvant systemic therapy (NST) are more likely to undergo breast-conserving therapy (BCT) than those who have primary surgery. However, the frequency with which patients who are not BCT-eligible prior to NST convert to BCT-eligible with treatment is unknown. To document this conversion rate in a subset of patients expected to have a high clinical response rate to NST, we studied surgical assessment and management of patients enrolled on a randomized neoadjuvant trial for stage II-III HER2-positive breast cancer (HER2 + BC)(CALGB 40601).

METHODS

The treating surgeon assessed BCT candidacy based on clinico-radiographic criteria both before and after NST. Definitive breast surgical management was at surgeon and patient discretion. We sought to determine (1) the conversion rate from BCT-ineligible to BCT-eligible (2) the percentage of BCT-eligible patients who chose breast conservation, and (3) the rate of successful BCT. We also evaluated surgeon-determined factors for BCT-ineligibility and the correlation between BCT eligibility and pathologic complete response (pCR).

RESULTS

Of 292 patients with pre- and post-NST surgical assessments, 59 % were non-BCT candidates at baseline. Of the 43 % of these patients who converted with NST, 67 % opted for BCT, with an 80 % success rate. NST increased the BCT-eligible rate from 41 to 64 %. Common factors cited for BCT-ineligibility prior to NST including tumor size (56 %) and probable poor cosmetic outcome (26 %) were reduced by 67 and 75 %, respectively, with treatment, while multicentricity, the second most common factor (33 %), fell by only 16 %. Since 23 % of the BCT-eligible patients chose mastectomy, BCT was the final surgical procedure in just 40 % of the patients. Patients considered BCT-eligible both at baseline and after NST had a pCR rate of 55 %, while patients who were BCT-ineligible prior to NST had the same pCR rate (44 %) whether they converted to BCT-eligible or not.

CONCLUSIONS

Many patients with HER2 + BC deemed ineligible for BCT at baseline can be converted to BCT-eligible with NST; excluding patients with multicentric disease substantially increases that percentage. In converted patients who opt for BCT, the success rate is similar to that of patients considered BCT-eligible at baseline. Whether a BCT-ineligible patient converts to BCT eligibility or not does not appear to affect the likelihood of achieving a pCR. Despite the efficacy of NST in this patient cohort, only 40 % of patients had successful BCT; further research into why BCT-eligible patients often opt for mastectomy is needed.