Extent of axillary surgery in inflammatory breast cancer: a survival analysis of 3500 patients

Guideline-Concordant Surgical Care for Lobular Versus Ductal Inflammatory Breast Cancer

INTRODUCTION

Quality of surgical care is understudied for lobular inflammatory breast cancer (IBC), which is less common, more chemotherapy-resistant, and more mammographically occult than ductal IBC. We compared guideline-concordant surgery (modified radical mastectomy [MRM] without immediate reconstruction following chemotherapy) for lobular versus ductal IBC.

METHODS

 Female individuals with cT4dM0 lobular and ductal IBC were identified in the National Cancer Database (NCDB) from 2010-2019. Modified radical mastectomy receipt was identified via codes for "modified radical mastectomy" or "mastectomy" and "≥10 lymph nodes removed" (proxy for axillary lymph node dissection). Descriptive statistics, chi-square tests, and t-tests were used.

RESULTS

A total of 1456 lobular and 10,445 ductal IBC patients were identified; 599 (41.1%) with lobular and 4859 (46.5%) with ductal IBC underwent MRMs (p = 0.001). Patients with lobular IBC included a higher proportion of individuals with cN0 disease (20.5% lobular vs. 13.7% ductal) and no lymph nodes examined at surgery (31.2% vs. 24.5%) but were less likely to be node-negative at surgery (12.7% vs. 17.1%, all p < 0.001). Among those who had lymph nodes removed at surgery, patients with lobular IBC also had fewer lymph nodes excised versus patients with ductal IBC (median [interquartile range], 7 (0-15) vs. 9 (0-17), p = 0.001).

CONCLUSIONS

Lobular IBC patients were more likely to present with node-negative disease and less likely to be node-negative at surgery, despite having fewer, and more frequently no, lymph nodes examined versus ductal IBC patients. Future studies should investigate whether these treatment disparities are because of surgical approach, pathologic assessment, and/or data quality as captured in the NCDB.

Axillary Surgery for Breast Cancer in 2024

Axillary surgery for patients with breast cancer (BC) in 2024 is becoming increasingly specific, moving away from the previous 'one size fits all' radical approach. The goal is to spare morbidity whilst maintaining oncologic safety. In the upfront surgery setting, a first landmark randomized controlled trial (RCT) on the omission of any surgical axillary staging in patients with unremarkable clinical examination and axillary ultrasound showed non-inferiority to sentinel lymph node (SLN) biopsy (SLNB). The study population consisted of 87.8% postmenopausal patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative BC. Patients with clinically node-negative breast cancer and up to two positive SLNs can safely be spared axillary dissection (ALND) even in the context of mastectomy or extranodal extension. In patients enrolled in the TAXIS trial, adjuvant systemic treatment was shown to be similar with or without ALND despite the loss of staging information. After neoadjuvant chemotherapy (NACT), targeted lymph node removal with or without SLNB showed a lower false-negative rate to determine nodal pathological complete response (pCR) compared to SLNB alone. However, oncologic outcomes do not appear to differ in patients with nodal pCR determined by either one of the two concepts, according to a recently published global, retrospective, real-world study. Real-world studies generally have a lower level of evidence than RCTs, but they are feasible quickly and with a large sample size. Another global real-world study provides evidence that even patients with residual isolated tumor cells can be safely spared from ALND. In general, few indications for ALND remain. Three randomized controlled trials are ongoing for patients with clinically node-positive BC in the upfront surgery setting and residual disease after NACT. Pending the results of these trials, ALND remains indicated in these patients.

Clinical outcomes after 1 versus 2-3 lines of neoadjuvant therapy in stage III inflammatory breast cancer

PURPOSE

Many stage III inflammatory breast cancer (IBC) patients experience a sufficient response to first-line (1L) neoadjuvant chemotherapy (NAC) to allow surgery, while some require additional NAC. We evaluated the pathologic complete response (pCR), breast cancer-free survival (BCFS) and overall survival (OS) among patients requiring 1 vs. 2-3 lines (L) of NAC prior to surgery.

METHODS

Stage III IBC patients from 2 institutions who received 1L or 2-3L of NAC prior to surgery were identified. Hormone receptor and HER2 status, grade, and pCR were evaluated. BCFS and OS were evaluated by the Kaplan-Meier method. Multivariable Cox models were utilized to estimate the hazard ratio (HR).

RESULTS

808 eligible patients (1997-2020) were identified (median age 51 years, median follow-up 69 months). 733 (91%) had 1L and 75 (9%) had 2-3L of NAC. Grade III, triple-negative and HER2-positive disease were more prevalent in 2-3L patients. 178 (24%) 1L and 14 (19%) 2-3L patients had pCR. 376 1L patients and 41 2-3L patients had recurrences. The 5-year BCFS was worse for the 2-3L group (33 vs. 46%, HR = 1.37; 95% CI 0.99-1.91). However, in 192 patients with a pCR, BCFS was similar (76 vs. 83% in 1L vs. 2-3L, respectively). There were 308 deaths (276 among 1L and 32 among 2-3L patients). The 5-year OS in 1L vs. 2-3L was 60 vs. 53% (HR = 1.32, 95% CI 0.91-1.93).

CONCLUSIONS

Among stage III IBC patients, pCR rates were similar, irrespective of the NAC lines number, and BCFS and OS were comparable with pCR after 1L and 2-3L.

Outcomes of Breast-Conserving Therapy in Patients With Inflammatory Breast Cancer: A Meta-Analysis

INTRODUCTION

Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer. Currently, patients who respond to neoadjuvant chemotherapy (NAC) are treated with mastectomy and axillary lymph node dissection. This study aimed to synthesize real-world data to evaluate the feasibility of breast-conserving therapy (BCT), sentinel lymph node (SLN), and sentinel lymph node biopsy (SLNB) for patients with IBC who respond to NAC.

METHODS

PubMed, Embase, and Cochrane Library databases were searched for relevant articles. Clinical studies that compared mastectomy with BCT for IBC treatment were reviewed. The primary outcomes were local recurrence rate and 5-y survival rate in patients with IBC who responded to NAC. Furthermore, the SLN detection rate and false-negative rate (FNR) for SLNB were also evaluated.

RESULTS

In the final analysis, 17 studies were included. The pooled estimates of the local recurrence rate for mastectomy and no surgical intervention were 18.6% and 15.9%, respectively (P = 0.956). Five-y survival was similar for mastectomy, partial mastectomy, and no surgical intervention (45.8%, 57.1%, and 39.4%, respectively). The pooled estimates of the SLN detection rate and FNR for SLNB were 81.9% and 21.8%, respectively.

CONCLUSIONS

Among patients with IBC who respond to NAC, the local recurrence and 5-y survival rates in those undergoing BCT are noninferior to the rates in those undergoing mastectomy; therefore, BCT could be a feasible option for surgical management. However, a poor SLN detection rate and a high FNR were found in patients undergoing SLNB. Further large-scale clinical studies are required to confirm our findings.

Identification of barriers at the primary care provider level to improve inflammatory breast cancer diagnosis and management

The purpose of this study, based in the United States, was to evaluate knowledge gaps and barriers related to diagnosis and care of inflammatory breast cancer (IBC), a rare but lethal breast cancer subtype, amongst Primary Care Providers (PCP) as they are often the first point of contact when patients notice initial symptoms. PCP participants in the Duke University Health System, federally qualified health center, corporate employee health and community practices, nearby academic medical center, Duke physician assistant and advanced practice nurse leadership program alumni were first selected in a convenience sample and for semi-structured interviews (n = 11). Based on these data, an online survey tool was developed and disseminated (n = 78) to assess salient measures of IBC diagnosis, health disparity factors, referral and care coordination practices, COVID-19 impact, and continuing medical education (CME). PCP reported access to care and knowledge gaps in symptom recognition (mean = 3.3, range 1-7) as major barriers. Only 31 % reported ever suspecting IBC in a patient. PCP (n = 49) responded being challenged with referral delays in diagnostic imaging. Additionally, since the COVID-19 pandemic started, 63 % reported breast cancer referral delays, and 33 % reported diagnosing less breast cancer. PCP stated interest in CME in their practice for improved diagnosis and patient care, which included online (53 %), lunch time or other in-service training (33 %), patient and provider-facing websites (32 %). Challenges communicating rare cancer information, gaps in confidence in diagnosing IBC, and timely follow-up with patients and specialists underscores the need for developing PCP educational modules to improve guideline-concordant care.

Low Rates of Local-Regional Recurrence Among Inflammatory Breast Cancer Patients After Contemporary Trimodal Therapy

BACKGROUND

Inflammatory breast cancer (IBC) represents a rare (2-3 %) but aggressive subset of breast cancer with a historically reported 5-year overall survival rate of 50 % and a 3-year local-regional recurrence (LRR) rate of 20 %. This study aimed to evaluate long-term LRR in a contemporary cohort of non-metastatic IBC patients undergoing trimodal therapy at a single institution and identify factors associated with local and distant failure.

METHODS

The study identified 262 patients with non-metastatic IBC who received trimodal therapy (neoadjuvant chemotherapy, modified radical mastectomy, adjuvant radiation) from an institutional prospective database (2007-2019). Long-term outcomes of local-regional and distant metastasis were reported. Survival outcomes were analyzed using the Cox proportional hazards regression model.

RESULTS

The median age at diagnosis was 52 years, and the median follow-up period was 5.1 years. In this cohort, 82 (31.3 %) patients achieved a pathologic complete response (pCR) in the breast and axilla. Local-regional recurrence was observed in 18 (6.9 %) patients (11 isolated to the chest wall, 4 isolated to regional nodes, and 3 involving chest wall and ipsilateral axillary nodes). Distant metastasis was observed in 92 (35.1 %) patients. During the follow-up period, 90 deaths occurred. In the multivariate analysis, pCR was associated with improved disease-free survival (hazard ratio [HR], 0.26; 95 % confidence interval [CI], 0.13-0.51; p = 0.001) and overall survival (HR, 0.31; 95 % CI, 0.15-0.65; p = 002).

CONCLUSIONS

During a median follow-up period longer than 5 years, the local-regional relapse rate for the IBC patients treated with contemporary trimodal therapy was 6.9%, similar to that for the non-IBC patients. After chemotherapy, surgical resection with modified radical mastectomy to negative margins and postmastectomy radiation therapy resulted in excellent long-term local-regional control.

Systematic Review and Meta-Analysis of Treatment Effects on Survival in Patients with Inflammatory Breast Cancer

The objective of this study was to determine the survival rate and the effects of different treatments on patients with inflammatory breast cancer (IBC). The study employed a systematic approach that included a search strategy across four databases: Embase, Web of Sciences, PubMed, and Scopus. The results obtained were screened initially by titles and abstracts, followed by full-texts in EndNote 8 software. The next stage involved data extraction and qualitative evaluation, where the Metan command was used to estimate the pooled survival rate. A total of 28 studies with a sample size of 63,796 were finally analyzed. The overall 3- and 5-year survival rates (OS) for IBC patients were found to be 52% (95% CI; 46-58%, I2: 99.42%) and 61% (95% CI; 53-69%, I2: 93.63%), respectively. The 5-year OS rates in patients with non-metastatic and metastatic IBC were 59% (95% CI; 54-63%, I2: 98.31%) and 30% (95% CI; 26-35%, I2: 50.84%), respectively. The 5-year OS rate in non-metastatic patients who underwent BCS surgery was 60% (CI 95%; 26-94%, I2: 95.13%). The overall 5- and 3-year OS rates for patients with IBC were lower than those for all types of breast cancer, and the rates were even lower in patients with metastasis. Therefore, it is recommended that healthcare workers and women at risk should be vigilant of early symptoms of IBC to prevent metastasis by seeking medical attention on time.

A Novel Preclinical Murine Model to Monitor Inflammatory Breast Cancer Tumor Growth and Lymphovascular Invasion

Inflammatory breast cancer (IBC), an understudied and lethal breast cancer, is often misdiagnosed due to its unique presentation of diffuse tumor cell clusters in the skin and dermal lymphatics. Here, we describe a window chamber technique in combination with a novel transgenic mouse model that has red fluorescent lymphatics (ProxTom RFP Nu/Nu) to simulate IBC clinicopathological hallmarks. Various breast cancer cells stably transfected to express green or red fluorescent reporters were transplanted into mice bearing dorsal skinfold window chambers. Intravital fluorescence microscopy and the in vivo imaging system (IVIS) were used to serially quantify local tumor growth, motility, length density of lymph and blood vessels, and degree of tumor cell lymphatic invasion over 0-140 h. This short-term, longitudinal imaging time frame in studying transient or dynamic events of diffuse and collectively migrating tumor cells in the local environment and quantitative analysis of the tumor area, motility, and vessel characteristics can be expanded to investigate other cancer cell types exhibiting lymphovascular invasion, a key step in metastatic dissemination. It was found that these models were able to effectively track tumor cluster migration and dissemination, which is a hallmark of IBC clinically, and was recapitulated in these mouse models.

Complete response in the axilla and the non-triple negative subtype are favourable prognostic factors for survival outcomes in inflammatory breast cancer

AIM

To assess real-world outcomes and prognostic factors of non-metastatic inflammatory breast cancer according to immunohistochemistry (IHC)-based subtype and treatment regimen.

METHODS

An institutional retrospective analysis of patients treated with neoadjuvant systemic treatment (NAST) for stage III inflammatory breast cancer diagnosed between 2001 and 2018 was performed. The survival outcomes in relation to patient characteristics, tumour characteristics, treatment modality and response to NAST were analyzed.

RESULTS

225 patients fulfilled the inclusion criteria, 90% of patients were node-positive. IHC-based subtypes: 39.1% were HR+/HER2-, 19.1% HR+/HER2+, 23.1% HR-/HER2+ and 18.7% HR-/HER2-. Treatment was multimodal: NAST (100%), surgery (94.2%) and radiotherapy (94.2%). 53.3% of patients received adjuvant endocrine therapy, 34.3% (neo)adjuvant trastuzumab. Tri-modality therapy was applied in 89.3% of patients. Following NAST, a pathologic complete remission (pCR) in the breast was found in 16.9%, in the axilla in 29.7% and in both the breast and axilla in 10.3% of patients. The axillary pCR rate was significantly higher in HR- subtypes. Median overall survival (OS) was 8.9, 7.2, 5.8 and 2.3 years (p < 0.001) for HR+/HER2-, HR+/HER2+, HR-/HER2+ and HR-/HER2- subtype, respectively. On multivariate analysis, IHC-based subtype, age and axillary pCR were found as independent prognostic factors for RFS and OS. pCR rate and median OS improved over time, 5.8% vs 14.7% and 4.7 vs 10.0 years (2001-2009 vs. 2010-2018), respectively.

CONCLUSIONS

Axillary pCR and the non-triple-negative IHC-based subtype are favourable prognostic factors for RFS and OS in inflammatory breast cancer. Introduction of taxanes and antiHER2 drugs contributed to improved pCR rate and OS.

Assessing Knowledge and Barriers at the Primary Care Provider Level that Contribute to Disparities in Inflammatory Breast Cancer Diagnosis and Treatment

Purpose

The purpose of this study was to evaluate knowledge gaps and barriers related to diagnosis and care of inflammatory breast cancer (IBC), a rare but most lethal breast cancer subtype, amongst Primary Care Providers (PCP) as they are often the first point of contact when patients notice initial symptoms.

Methods

PCP participants within Duke University Health System, federally qualified health center, corporate employee health and community practices, nearby academic medical center, Duke physician assistant, and nurse leadership program alumni were first selected in a convenience sample (n=11) for semi-structured interviews (n=11). Based on these data, an online survey tool was developed and disseminated (n=78) to assess salient measures of IBC diagnosis, health disparity factors, referral and care coordination practices, COVID impact, and continued medical education (CME).

Results

PCP reported access to care and knowledge gaps in symptom recognition (mean = 3.3, range 1-7) as major barriers. Only 31% reported ever suspecting IBC in a patient. PCP (n=49) responded being challenged with referral delays in diagnostic imaging. Additionally, since the COVID-19 pandemic started, 63% reported breast cancer referral delays, and 33% reported diagnosing less breast cancer. PCP stated interest in CME in their practice for improved diagnosis and patient care, which included online (53%), lunch time or other in-service training (33%), patient and provider-facing websites (32%).

Conclusions

Challenges communicating rare cancer information, gaps in confidence in diagnosing IBC, and timely follow-up with patients and specialists underscores the need for developing PCP educational modules to improve guideline-concordant care.

Proactive Immunotherapeutic Approaches against Inflammatory Breast Cancer May Improve Patient Outcomes

Inflammatory breast cancer (IBC) is highly metastatic at the onset of the disease with no IBC-specific treatments, resulting in dismal patient survival. IBC treatment is a clear unmet clinical need. This commentary highlights findings from a recent seminal approach in which pembrolizumab, a checkpoint inhibitor against programmed cell death protein 1 (PD-1), was provided to a triple-negative IBC patient as a neoadjuvant immune therapy combined with anthracycline–taxane-based chemotherapy. We highlight the findings of the case report and offer a perspective on taking a proactive approach to deploy approved immune checkpoint inhibitors. On the basis of our recently published research study, we propose in situ vaccination with direct injection of immunostimulatory agents into the tumor as an option to improve outcomes safely, effectively, and economically for IBC patients.

Inflammatory Breast Cancer: Is There a Role for Deescalation of Surgery?

Inflammatory breast cancer (IBC) is a rare and aggressive presentation of breast cancer, characterized by higher propensity for locoregional recurrence and distant metastasis compared with non-IBC. Because of extensive parenchymal and overlying dermal lymphatic involvement by carcinoma, IBC is unresectable at diagnosis. Trimodality therapy (neoadjuvant chemotherapy followed by modified radical mastectomy and adjuvant comprehensive chest wall and regional nodal radiotherapy) has been a well-accepted treatment algorithm for IBC. Over the last few decades, several innovations in systemic therapy have resulted in rising rates of pathologic complete response (pCR) in both the affected breast and the axilla. The latter may present an opportunity for deescalation of lymph node surgery in patients with IBC, as those with an axillary pCR may be able to avoid an axillary dissection. To this end, feasibility data are necessary to address this question. There are very limited data on the safety of breast conservation of IBC; therefore, mastectomy remains the standard of care for this disease. There are also no data addressing the safety of immediate reconstruction in patients with IBC. Considering that some degree of deliberate skin-sparing to facilitate immediate breast reconstruction would be expected, given the extensive skin involvement by disease at diagnosis, the safest oncologic strategy to breast reconstruction in IBC would be the delayed approach.

Neoadjuvant in situ vaccination with cowpea mosaic virus as a novel therapy against canine inflammatory mammary cancer

Background

Inflammatory mammary cancer (IMC), the counterpart of human inflammatory breast cancer (IBC), is the deadliest form of canine mammary tumors. IMC patients lack specific therapy and have poor outcomes. This proof-of-principle preclinical study evaluated the efficacy, safety, and effect on survival of neoadjuvant intratumoral (in situ) empty cowpea mosaic virus (eCPMV) immunotherapy in companion dogs diagnosed with IMC.

Methods

Ten IMC-bearing dogs were enrolled in the study. Five dogs received medical therapy, and five received weekly neoadjuvant in situ eCPMV immunotherapy (0.2–0.4 mg per injection) and medical therapy after the second eCPMV injection. Efficacy was evaluated by reduction of tumor growth; safety by hematological and biochemistry changes in blood and plasma; and patient outcome by survival analysis. eCPMV-induced immune changes in blood cells were analyzed by flow cytometry; changes in the tumor microenvironment were evaluated by CD3 (T lymphocytes), CD20 (B lymphocytes), FoxP3 (Treg lymphocytes), myeloperoxidase (MPO; neutrophils), Ki-67 (proliferation index, PI; tumor cell proliferation), and Cleaved Caspase-3 (CC-3; apoptosis) immunohistochemistry.

Results

Two neoadjuvant in situ eCPMV injections resulted in tumor shrinkage in all patients by day 14 without systemic adverse events. Although surgery for IMC is generally not an option, reduction in tumor size allowed surgery in two IMC patients. In peripheral blood, in situ eCPMV immunotherapy was associated with a significant decrease of Treg+/CD8+ ratio and changes in CD8+Granzyme B+ T cells, which behave as a lagging predictive biomarker. In the TME, higher neutrophilic infiltration and MPO expression, lower tumor Ki-67 PI, increase in CD3+ lymphocytes, decrease in FoxP3+/CD3+ ratio (p<0.04 for all comparisons), and no changes in CC-3+ immunostainings were observed in post-treatment tumor tissues when compared with pretreatment tumor samples. eCPMV-treated IMC patients had a statistically significant (p=0.033) improved overall survival than patients treated with medical therapy.

Conclusions

Neoadjuvant in situ eCPMV immunotherapy demonstrated anti-tumor efficacy and improved survival in IMC patients without systemic adverse effects. eCPMV-induced changes in immune cells point to neutrophils as a driver of immune response. Neoadjuvant in situ eCPMV immunotherapy could be a groundbreaking immunotherapy for canine IMC and a potential future immunotherapy for human IBC patients.

Current Surgical Management of Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer characterized by erythema and edema of at least one-third of the breast. The diagnosis remains a clinical one. Standard of care involves trimodality therapy with anthracycline-based neoadjuvant chemotherapy and human epidermal growth factor receptor 2 (HER2)-directed therapy if HER2 positive, followed by modified radical mastectomy and post-mastectomy radiation therapy to the chest wall in addition to regional nodal basins including supraclavicular and internal mammary nodes. Current evidence does not support de-escalation of surgical therapy in the breast and axilla in IBC, and positive surgical margins have been associated with worse outcomes. Furthermore, sentinel node biopsy for axillary staging has a high false negative rate prohibiting its use in IBC. Delayed reconstruction is recommended for IBC due to a high recurrence rate and a potential for delay in adjuvant therapy. Contralateral prophylactic mastectomy may be considered at the time of delayed reconstruction. In this paper, we discuss available evidence and controversies in the current surgical management of patients with IBC.

Mini review: The FDA-approved prescription drugs that target the MAPK signaling pathway in women with breast cancer

Breast cancer (BC) is the most common cancer and the prevalent type of malignancy among women. Multiple risk factors, including genetic changes, biological age, dense breast tissue, and obesity are associated with BC. The mitogen-activated protein kinases (MAPK) signaling pathway has a pivotal role in regulating biological functions such as cell proliferation, differentiation, apoptosis, and survival. It has become evident that the MAPK pathway is associated with tumorigenesis and may promote breast cancer development. The MAPK/RAS/RAF cascade is closely associated with breast cancer. RAS signaling can enhance BC cell growth and progression. B-Raf is an important kinase and a potent RAF isoform involved in breast tumor initiation and differentiation. Depending on the reasons for cancer, there are different strategies for treatment of women with BC. Till now, several FDA-approved treatments have been investigated that inhibit the MAPK pathway and reduce metastatic progression in breast cancer. The most common breast cancer drugs that regulate or inhibit the MAPK pathway may include Farnesyltransferase inhibitors (FTIs), Sorafenib, Vemurafenib, PLX8394, Dabrafenib, Ulixertinib, Simvastatin, Alisertib, and Teriflunomide. In this review, we will discuss the roles of the MAPK/RAS/RAF/MEK/ERK pathway in BC and summarize the FDA-approved prescription drugs that target the MAPK signaling pathway in women with BC.

Update on systemic treatment for newly diagnosed inflammatory breast cancer

Background

Inflammatory breast cancer (IBC) is a rare and aggressive disease, accounting for 2-4% of new cases of breast cancer. Owing to its aggressive nature, IBC represent approximately 8-10% of breast cancer deaths. Management of IBC requires a multidisciplinary team for decision-making involving a composite of systemic treatment, surgery, and radiation, or "Trimodality Treatment." Because of the rarity of the disease, systemic therapy of IBC traditionally has been extrapolated from non-IBC clinical trials.

Aim of Review

The purpose of this review is to provide an overview of the development of systemic treatment of IBC from the past to the present by focusing on IBC clinical trials, including chemotherapy and targeted therapies.

Key Scientific Concepts of Review

We discuss their effects on pathologic complete response (pCR) and survival outcomes, the predictive markers, and the adverse events of these therapies. Further, we summarized the current standard treatment stratified by molecular subtypes based on clinical data. Finally, we discuss the future trend of systemic therapy, including immunotherapy and ongoing IBC clinical trials.

Locoregional Management of Inflammatory Breast Cancer

Purpose of Review

Inflammatory breast cancer (IBC) is a biologically aggressive subtype with a high risk for rapid local progression and early distant metastasis. We review the updated data for optimal locoregional management of IBC, including areas of active controversy.

Recent Findings

Advancements in tri-modality therapies have improved survival among IBC patients in recent years; however, the risk of locoregional and distant recurrence remains high, particularly in triple-negative IBC. Data to support de-escalation of surgery or radiotherapy is limited, and the recommended treatment approach for non-metastatic IBC remains preoperative systemic therapy (PST), modified radical mastectomy (MRM), and adjuvant radiotherapy in all patients. For patients with de novo metastatic disease, locoregional intervention may be appropriate.

Summary

Optimal locoregional management of IBC remains PST followed by MRM and adjuvant radiotherapy. With increasingly effective systemic therapies, research to identify a subset of patients who may benefit from de-escalation of locoregional therapies is warranted.

The Prognostic Value of Axillary Staging Following Neoadjuvant Chemotherapy in Inflammatory Breast Cancer

BACKGROUND

Inflammatory breast cancer (IBC) has historically been characterized by high rates of recurrence and poor survival; however, there have been significant improvements in systemic therapy. We sought to investigate modern treatment of IBC and define the yield and prognostic significance of axillary lymph nodes after neoadjuvant chemotherapy (NAC).

METHODS

Women with clinical stage T4d, N0-N3, M0 IBC from 2012 to 2016 in the National Cancer Database were included. Kaplan-Meier survival curves and Cox regression were used to assess mortality by receptor subtype and nodal status.

RESULTS

We identified 5265 patients; 37% hormone receptor (HR) +/HER2 - , 19% HR +/HER2 + , 18% HR -/HER2 + , and 26% triple-negative, and 5-year overall survival was 51.6%. Only 34% were treated according to guidelines with NAC, modified radical mastectomy, and adjuvant radiation. Pathologically positive lymph nodes (ypN +) after NAC varied by subtype and clinical nodal status (cN) ranging from 82% in cN + HR +/HER2 - patients to 19% in cN0 HR -/HER2 + patients. ypN + strongly correlated with survival in all subtypes with the most pronounced impact in HR +/HER2 + patients, with 90% 5-year overall survival in ypN0 versus 66% for ypN + (HR 4.29, 95% CI 1.58-11.70, p = 0.03).

CONCLUSIONS

Five-year survival in M0 IBC is 51.6%. Positive nodes after NAC varied by subtype and clinical N status but is sufficiently high and provided meaningful prognostication in all subtypes to support continued routine pathologic assessment. Future study is warranted to identify reliable, less morbid, methods of staging the axilla in IBC patients appropriate for deescalation of axillary surgery.

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.