Self-Reported Management of Inflammatory Breast Cancer Among the American Society of Breast Surgeons Membership: Consensus and Opportunities

BACKGROUND

Inflammatory breast cancer (IBC) is rare and biologically aggressive. We sought to assess diagnostic and management strategies among the American Society of Breast Surgeons (ASBrS) membership.

PATIENTS AND METHODS

An anonymous survey was distributed to ASBrS members from March to May 2023. The survey included questions about respondents' demographics and information related to stage III and IV IBC management. Agreement was defined as a shared response by >80% of respondents. In areas of disagreement, responses were stratified by years in practice, fellowship training, and annual IBC patient volume.

RESULTS

The survey was administered to 2337 members with 399 (17.1%) completing all questions and defining the study cohort. Distribution of years in practice was 26.0% 0-10 years, 26.6% 11-20 years and 47.4% > 20 years. Overall, 51.2% reported surgical oncology or breast fellowship training, 69.2% maintain a breast-only practice, and 73.5% treat < 5 IBC cases/year. Agreement was identified in diagnostic imaging, trimodal therapy, and mastectomy with wide skin excision for stage III IBC. Lack of agreement was identified in surgical management of the axilla; respondents with < 10 years in practice or fellowship training were more likely to perform axillary dissection for cN0-N2 stage III IBC. Locoregional management of stage IV IBC was variable.

CONCLUSIONS

Among ASBrS members, there is consensus in diagnostic evaluation, treatment sequencing and surgical approach to the breast in stage III IBC. Differences exist in surgical management of the cN0-2 axilla with uptake of de-escalation strategies. Clinical trials are needed to evaluate oncologic safety of de-escalation in this high-risk population.

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.

TBCRC 039: a phase II study of preoperative ruxolitinib with or without paclitaxel for triple-negative inflammatory breast cancer

BACKGROUND

Patients with inflammatory breast cancer (IBC) have overall poor clinical outcomes, with triple-negative IBC (TN-IBC) being associated with the worst survival, warranting the investigation of novel therapies. Preclinical studies implied that ruxolitinib (RUX), a JAK1/2 inhibitor, may be an effective therapy for TN-IBC.

METHODS

We conducted a randomized phase II study with nested window-of-opportunity in TN-IBC. Treatment-naïve patients received a 7-day run-in of RUX alone or RUX plus paclitaxel (PAC). After the run-in, those who received RUX alone proceeded to neoadjuvant therapy with either RUX + PAC or PAC alone for 12 weeks; those who had received RUX + PAC continued treatment for 12 weeks. All patients subsequently received 4 cycles of doxorubicin plus cyclophosphamide prior to surgery. Research tumor biopsies were performed at baseline (pre-run-in) and after run-in therapy. Tumors were evaluated for phosphorylated STAT3 (pSTAT3) by immunostaining, and a subset was also analyzed by RNA-seq. The primary endpoint was the percent of pSTAT3-positive pre-run-in tumors that became pSTAT3-negative. Secondary endpoints included pathologic complete response (pCR).

RESULTS

Overall, 23 patients were enrolled, of whom 21 completed preoperative therapy. Two patients achieved pCR (8.7%). pSTAT3 and IL-6/JAK/STAT3 signaling decreased in post-run-in biopsies of RUX-treated samples, while sustained treatment with RUX + PAC upregulated IL-6/JAK/STAT3 signaling compared to RUX alone. Both treatments decreased GZMB+ T cells implying immune suppression. RUX alone effectively inhibited JAK/STAT3 signaling but its combination with PAC led to incomplete inhibition. The immune suppressive effects of RUX alone and in combination may negate its growth inhibitory effects on cancer cells.

CONCLUSION

In summary, the use of RUX in TN-IBC was associated with a decrease in pSTAT3 levels despite lack of clinical benefit. Cancer cell-specific-targeting of JAK2/STAT3 or combinations with immunotherapy may be required for further evaluation of JAK2/STAT3 signaling as a cancer therapeutic target.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov , NCT02876302. Registered 23 August 2016.

Treatment Response, Tumor Infiltrating Lymphocytes and Clinical Outcomes in Inflammatory Breast Cancer-Treated with Neoadjuvant Systemic Therapy

Inflammatory breast cancer (IBC) is a rare (1%-5%), aggressive form of breast cancer, accounting for approximately 10% of breast cancer mortality. In the localized setting, standard of care is neoadjuvant chemotherapy (NACT) ± anti-HER2 therapy, followed by surgery. Here we investigated associations between clinicopathologic variables, stromal tumor-infiltrating lymphocytes (sTIL), and pathologic complete response (pCR), and the prognostic value of pCR. We included 494 localized patients with IBC treated with NACT from October 1996 to October 2021 in eight European hospitals. Standard clinicopathologic variables were collected and central pathologic review was performed, including sTIL. Associations were assessed using Firth logistic regression models. Cox regressions were used to evaluate the role of pCR and residual cancer burden (RCB) on disease-free survival (DFS), distant recurrence-free survival (DRFS), and overall survival (OS). Distribution according to receptor status was as follows: 26.4% estrogen receptor negative (ER-)/HER2-; 22.0% ER-/HER2+; 37.4% ER+/HER2-, and 14.1% ER+/HER2+. Overall pCR rate was 26.3%, being highest in the HER2+ groups (45.9% for ER-/HER2+ and 42.9% for ER+/HER2+). sTILs were low (median: 5.3%), being highest in the ER-/HER2- group (median: 10%). High tumor grade, ER negativity, HER2 positivity, higher sTILs, and taxane-based NACT were significantly associated with pCR. pCR was associated with improved DFS, DRFS, and OS in multivariable analyses. RCB score in patients not achieving pCR was independently associated with survival. In conclusion, sTILs were low in IBC, but were predictive of pCR. Both pCR and RCB have an independent prognostic role in IBC treated with NACT.

SIGNIFICANCE

IBC is a rare, but very aggressive type of breast cancer. The prognostic role of pCR after systemic therapy and the predictive value of sTILs for pCR are well established in the general breast cancer population; however, only limited information is available in IBC. We assembled the largest retrospective IBC series so far and demonstrated that sTIL is predictive of pCR. We emphasize that reaching pCR remains of utmost importance in IBC.

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.

Conservative Surgery in cT4 Breast Cancer: Single-Center Experience in the Neoadjuvant Setting

BACKGROUND

The diffusion of screening programs has resulted in a decrease of cT4 breast cancer diagnosis. The standard care for cT4 was neoadjuvant chemotherapy (NA), surgery, and locoregional or adjuvant systemic therapies. NA allows two outcomes: 1. improve survival rates, and 2. de-escalation of surgery. This de-escalation has allowed the introduction of conservative breast surgery (CBS). We evaluate the possibility of submitting cT4 patients to CBS instead of radical breast surgery (RBS) by assessing the risk of locoregional disease-free survival, (LR-DFS) distant disease-free survival (DDFS), and overall survival (OS).

METHODS

This monocentric, retrospective study evaluated cT4 patients submitted to NA and surgery between January 2014 and July 2021. The study population included patients undergoing CBS or RBS without immediate reconstruction. Survival curves were obtained using the Kaplan-Meyer method and compared using a Log Rank test.

RESULTS

At a follow-up of 43.7 months, LR-DFS was 70% and 75.9%, respectively, in CBS and RBS (p = 0.420). DDFS was 67.8% and 29.7%, respectively, (p = 0.122). OS was 69.8% and 59.8%, respectively, (p = 0.311).

CONCLUSIONS

In patients with major or complete response to NA, CBS can be considered a safe alternative to RBS in the treatment of cT4a-d stage. In patients with poor response to NA, RBS remained the best surgical choice.

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.

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.

MRI Changes in Breast Skin Following Preoperative Therapy for Patients with Inflammatory Breast Cancer

RATIONALE AND OBJECTIVES

Preoperative systemic therapy (PST) followed by mastectomy and radiation improves survival for patients with inflammatory breast cancer (IBC). Residual disease within the skin post-PST adversely impacts surgical outcome and risk of local-regional recurrence (LRR). We aimed to assess magnetic resonance imaging (MRI) breast skin changes post-PST with pathologic response and its impact on surgical resectability.

MATERIALS AND METHODS

We retrospectively reviewed 152 baseline and post-PST breast MRIs of 76 patients with IBC. Using the ACR-BIRADS MRI lexicon, we correlated skin thickness, qualitative enhancement, and kinetic analysis with pathologic response in the skin at mastectomy.

RESULTS

Baseline MRI showed skin thickening in all 76 patients, 75/76 (99%) showed skin enhancement, 54/75 (72%) had medium/fast initial kinetics, usually with persistent delayed kinetics in 49/54 (91%). Following PST, 66/76 (87%) had residual skin thickening with 64/76 (84%) showing a decrease; 33/76 (43%) had persistent enhancement. The median thickness post-PST was 4.7 mm with residual tumor in the skin, and 3.0 mm without residual tumor (p = 0.008). Regardless of pathologic response, the majority of patients had persistent skin thickening on MRI following PST (100% [14/14] with residual tumor and 84% [52/62] without residual tumor). There was no association between post-PST skin thickness on breast MRI and rate of LRR.

CONCLUSION

Patients with IBC have skin thickening and enhancement on baseline breast MRI, with a statistically significant reduction in skin thickness following successful PST. Despite persistent skin changes on MRI, patients achieving a partial or complete parenchymal response to PST may proceed to mastectomy with low LRR rates.

Comparison of survival in non-metastatic inflammatory and other T4 breast cancers: a SEER population-based analysis

Background

Previous studies have reported poor survival rates in inflammatory breast cancer (IBC) patients than non-inflammatory local advanced breast cancer (non-IBC) patients. However, until now, the survival rate of IBC and other T4 non-IBC (T4-non-IBC) patients remains unexplored.

Methods

Surveillance, Epidemiology, and End Results (SEER) database was searched to identify cases with confirmed non-metastatic IBC and T4-non-IBC who had received surgery, chemotherapy, and radiotherapy between 2010 and 2015. IBC was defined as per the American Joint Committee on Cancer (AJCC) 7th edition. Breast Cancer-Specific Survival (BCSS) was estimated by plotting the Kaplan-Meier curve and compared across groups by using the log-rank test. Cox model was constructed to determine the association between IBC and BCSS after adjusting for age, race, stage of disease, tumor grade and surgery type.

Results

Out of a total of 1986 patients, 37.1% had IBC and mean age was 56.6 ± 12.4. After a median follow-up time of 28 months, 3-year BCSS rate for IBC and T4-non-IBC patients was 81.4 and 81.9%, respectively (log-rank p = 0.398). The 3-year BCSS rate in HR−/HER2+ cohort was higher for IBC patients than T4-non-IBC patients (89.5% vs. 80.8%; log-rank p = 0.028), and in HR−/HER2- cohort it was significantly lower for IBC patients than T4-non-IBC patients (57.4% vs. 67.5%; log-rank p = 0.010). However, it was identical between IBC and T4-non-IBC patients in both HR+/HER2- (85.0% vs. 85.3%; log-rank p = 0.567) and HR+/HER2+ (93.6% vs. 91.0%, log-rank p = 0.510) cohorts. After adjusting for potential confounding variables, we observed that IBC is a significant independent predictor for survival of HR−/HER2+ cohort (hazards ratio [HR] = 0.442; 95% CI: 0.216–0.902; P = 0.025) and HR−/HER2- cohort (HR = 1.738; 95% CI: 1.192–2.534; P = 0.004).

Conclusions

Patients with IBC and T4-non-IBC had a similar BCSS in the era of modern systemic treatment. In IBC patients, the HR−/HER2+ subtype is associated with a better outcome, and HR−/HER2- subtype is associated with poorer outcomes as compared to the T4-non-IBC patients.

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.

Biological subtype, treatment response and outcomes in inflammatory breast cancer using data from the National Cancer Database

BACKGROUND

Although inflammatory breast cancer (IBC) is postulated to be a distinct biological entity, practice guidelines and previous data suggest that treatment and outcomes are influenced by standard approximated biological subtype. The aim of this study was validation in a large recent National Cancer Database (NCDB) patient cohort.

METHODS

Patients with non-metastatic IBC treated in 2010-2015 with neoadjuvant systemic therapy and surgery were identified from the NCDB. Approximated biological subtypes were categorized as oestrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-), ER-/HER2- and HER2+. Total pathological complete response (pCR) was defined as ypT0/ypTis, ypN0. χ² tests were used to compare pCR rates, and Kaplan-Meier curves and Cox proportional hazards regression to analyse overall survival.

RESULTS

Among 4068 patients with IBC (median age 56 years), the approximated biological subtype was ER+/HER2- in 1575 (38·7 per cent), HER2+ in 1323 (32·5 per cent) and ER-/HER2- in 1170 (28·8 per cent). A total of 3351 patients (84·0 per cent) were cN+ at presentation, with no differences across subtypes. Total pCR rates varied significantly by subtype: ER+/HER2- (6·2 per cent), HER2+ (38·8 per cent), ER-/HER2- (19·1 per cent) (P < 0·001), as did breast pCR rates (10·4, 44·5 and 25·2 per cent respectively) and nodal pCR rates (16·9, 56·9 and 33·1 per cent). The 5-year overall survival rate varied significantly across subtypes (ER+/HER2- 64·9 per cent, HER2+ 74·0 per cent, ER-/HER2- 44·0 per cent; P < 0·001) and by pCR within subtypes (all P < 0·001). In multivariable analysis, ER-/HER2- subtype (hazard ratio 2·89 versus HER2+ as reference; P < 0·001) and absence of total pCR (hazard ratio 3·23; P < 0·001) predicted worse survival.

CONCLUSION

Both treatment response and survival in patients with IBC varied with approximated biological subtype, as among other invasive breast cancers. These data support continued tailoring of systemic treatment to approximated biological subtype and highlight the recent improved outcomes in patients with HER2+ disease.

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

PURPOSE

Inflammatory breast cancer (IBC) is an aggressive variant for which axillary lymph node (LN) dissection following neoadjuvant chemotherapy (NACT) remains standard of care. But with increasingly effective systemic therapy, it is unclear whether more limited axillary surgery may be appropriate in some IBC patients. We sought to examine whether extent of axillary LN surgery was associated with overall survival (OS) for IBC.

METHODS

Female breast cancer patients with non-metastatic IBC (cT4d) diagnosed 2010-2014 were identified in the National Cancer Data Base. Cox proportional hazards modeling was used to estimate the association between extent of axillary surgery (≤ 9 vs ≥ 10 LNs removed) and OS after adjusting for covariates, including post-NACT nodal status (ypN0 vs ypN1-3) and radiotherapy receipt (yes/no).

RESULTS

3471 patients were included: 597 (17.2%) had cN0 disease, 1833 (52.8%) had cN1 disease, and 1041 (30%) had cN2-3 disease. 49.9% of cN0 patients were confirmed to be ypN0 on post-NACT surgical pathology. Being ypN0 (vs ypN1-3) was associated with improved adjusted OS for all patients. Radiotherapy was associated with improved adjusted OS for cN1 and cN2-3 patients but not for cN0 patients. Regardless of ypN status, there was a trend towards improved adjusted OS with having ≥ 10 (vs ≤ 9) LNs removed for cN2-3 patients (HR 0.78, 95% CI 0.60-1.01, p = 0.06) but not for cN0 patients (p = 0.83).

CONCLUSIONS

A majority of IBC patients in our study presented with node-positive disease, and for those presenting with cN2-3 disease, more extensive axillary surgery is potentially associated with improved survival. For cN0 patients, however, more extensive axillary surgery was not associated with a survival benefit, suggesting an opportunity for more personalized care.

Inflammatory Breast Cancer: a Separate Entity

PURPOSE OF REVIEW

Inflammatory breast cancer (IBC) is an uncommon but highly aggressive subtype of breast cancer that contributes significantly to breast cancer-related mortality. In this review, we provide an overview of the clinical and molecular characteristics of IBC, and highlight some areas of need for ongoing research.

RECENT FINDINGS

The disease is characterized by florid tumor emboli that obstruct dermal lymphatics, leading to swelling and inflammation of the affected breast. Recent studies have focused on tumor cell intrinsic features, such as signaling through pathways involved in growth and stem-like behavior, as well as extrinsic features, such as the immune system, that can be leveraged to develop new potential therapies. Key efforts have led to an increase in awareness of the disease as well as new insights into IBC pathogenesis. However, there is a strong need for new therapies designed specifically for IBC, and many unanswered questions remain.

Downregulation of MMSET impairs breast cancer proliferation and metastasis through inhibiting Wnt/β-catenin signaling

BACKGROUND

Recently, the biggest challenge in the treatment of breast cancer is the metastasis of breast cancer cells. Multiple myeloma SET protein (MMSET), a histone lysine methyltransferase, overexpressed in various human cancers, was reported to be associated with carcinogenesis of human cancers.

METHODS

Expression of MMSET in breast cancer cell lines and tissues was quantified by real-time PCR and Western blotting. Immunohistochemistry was employed to analyze MMSET expression in 163 clinicopathologically characterized breast cancer cases. Cell functional assays such as MTT assay, colony formation, BrdU assay, flow cytometry, wound healing, Transwell assay, and 3D culture were used to investigate the effect of MMSET in the development and metastasis of human breast cancer. Effects of MMSET on Wnt/β-catenin signaling pathway were further studied by using Western blotting analysis.

RESULTS

Our results showed that MMSET expression was markedly overexpressed in breast cancer cells and clinical specimens and was significantly correlated with patients' clinicopatho-logic characteristics and prognosis. Moreover, silencing endogenous MMSET significantly inhibited the proliferation, migration, and metastasis of breast cancer cells through inhibiting the Wnt/β-catenin pathway.

CONCLUSION

This study found that the downregulated expression of MMSET impaired proliferation and metastasis of human breast cancer through inhibiting Wnt/β-catenin signaling pathway. Notably, our results indicated that MMSET could be a useful biomarker for the prognosis of breast cancer.

Inflammatory breast cancer outcomes by breast cancer subtype: a population-based study

AIM

To assess the outcomes of breast cancer subtype in inflammatory breast cancer (IBC).

METHODS

We retrospectively assessed IBC patients from the SEER program.

RESULTS

We identified 626 patients, including 230 (36.7%),100 (17.6%), 113 (18.1%), and 173 (27.6%) patients with HoR+/HER2-, HoR+/HER2+, HoR-/HER2+, and HoR-/HER2- subtype disease, respectively. Multivariate analysis demonstrated that, using HoR+/HER2- subtype as reference, patients with HoR+/HER2+ subtype had better breast cancer-specific survival (BCSS) and overall survival (OS), and patients with HoR-/HER2- subtype had worse BCSS and OS, while BCSS and OS were comparable for HoR-/HER2+ subtype. Similar trends were observed in patients who received surgery, radiotherapy, chemotherapy or trimodality therapy.

CONCLUSION

Breast cancer subtype is clinically useful for predicting survival outcome in IBC. The HoR+/HER2- subtype shows poorer survival outcome than HoR+/HER2+ subtype.

Does nonmetastatic inflammatory breast cancer have a worse prognosis than other nonmetastatic T4 cancers?

BACKGROUND

Both patients with inflammatory breast cancer (IFLBC) and patients with noninflammatory T4 breast cancer (non-IFLBC) have a heavy disease burden in the breast; whether the unique biology of IFLBC conveys a higher locoregional recurrence (LRR) risk and worse outcomes in comparison with other T4 lesions is uncertain. Here the outcomes of patients with IFLBC and patients with non-IFLBC treated with modern multimodality therapy are compared.

METHODS

Patients with nonmetastatic T4 breast cancer treated with neoadjuvant chemotherapy, mastectomy, and radiation therapy between 2006 and 2016 were identified. Recurrences and survival were compared between patients with IFLBC and patients with non-IFLBC overall and stratified by receptor subtype.

RESULTS

For 199 T4 patients, the median age was 52 years, and the median clinical tumor size was 7 cm. One hundred seventeen (59%) had IFLBC. With a median follow-up of 41 months, 4 patients had isolated LRR; all cases occurred in patients with IFLBC. The 5-year isolated LRR rate for patients with IFLBC was 4.8%. Overall, 14 patients had both LRR and distant recurrence (DR); 47 had DR only. The 5-year distant recurrence-free survival (DRFS) rates were similar for patients with IFLBC and patients with non-IFLBC (63% vs 71%; log-rank P = .14). The 5-year DRFS rate was lowest among triple-negative (TN) patients (43%) and was significantly lower for patients with TN IFLBC versus patients with non-IFLBC (28% vs 62%; log-rank P = .02). The 5-year overall survival rates (71% vs 74%; log-rank P = .4) and cancer-specific survival rates (74% vs 79%; log-rank P = .23) did not differ between IFLBC and non-IFLBC.

CONCLUSIONS

Although IFLBC is often considered a unique biologic subtype, patients with IFLBC and patients with non-IFLBC had similar outcomes with modern multimodality therapy; isolated LRR was uncommon. The TN subtype in patients with IFLBC is associated with poor outcomes, and this indicates the need for new treatment approaches in this group.

Radiation therapy for inflammatory breast cancer

Inflammatory Breast Cancer (IBC) is a rare and very aggressive breast cancer, still associated with poor prognosis. Therefore, management of IBC requires carefully integrated care, and ideally, patients should be evaluated in a multidisciplinary team from the beginning, to identify the best treatment strategy. IBC is usually unresectable at presentation, and neo-adjuvant systemic therapy is considered the standard of care. Response to the primary treatment, especially pathological complete response (pCR), is important to move forward to definitive local therapy with the goal to improve survival. In any case, regardless the response to neo-adjuvant therapy, surgery and radiotherapy should administered to ensure a better loco-regional tumor control. Mastectomy with axillary lymph node dissection followed by chest wall and regional nodal radiotherapy is the most frequent approach, and whether breast-conserving surgery could be preferable in some selected groups of patients with clinical complete response is still a debated question. Radiotherapy alone has recommended only in cases of persistent unresectability. To date, the approach remains as established in the current recommendations, with the best option for trimodality treatment, and further studies clearly warranted.

Factors associated with improved outcomes for metastatic inflammatory breast cancer patients

PURPOSE

Controversy exists regarding the role of locoregional therapy for stage IV inflammatory breast cancer (IBC). This study aims to determine indicators of prognosis, including primary tumor resection, for stage IV IBC patients.

METHODS

Using the National Cancer Data Base, female patients diagnosed 2010-2013 with unilateral a priori metastatic T4d invasive adenocarcinoma of the breast were identified. We conducted propensity score matched analysis to balance confounders of surgery versus no-surgery. Stratified log-rank test and double-robust estimation under the Cox model were used to assess the effect of surgery, and margins, on overall survival (OS) in the propensity score matched cohort.

RESULTS

Of 1266 patients, 41% underwent surgery. In the unmatched cohort, median OS of the surgery and no-surgery groups was 36 and 20 months, respectively (p < 0.001). In the matched cohort (n = 588), the median OS of surgery and no-surgery groups was 29 and 27 months, respectively (p = 0.052). Patients with negative margin surgery (p = 0.024), hormone receptor-positive (p = 0.019), HER2-positive disease (p < 0.0001), treated with chemotherapy (p < 0.0001) and hormonal therapy (p < 0.0001), had better survival. Those with brain metastases had increased risk of death (p < 0.0001).

CONCLUSION

This study represents the largest cohort of metastatic IBC patients, and identified negative margin surgery, systemic therapy, hormone receptor and HER2-positive disease as factors associated with improved outcomes. While these findings should be interpreted cautiously, they may be used to guide further investigations into local control and quality of life in this patient population with limited treatment options.