Inflammatory breast cancer and chest wall disease: The oncologist perspective

Immunotherapy for inflammatory breast cancer: current evidences and future perspectives

PURPOSE OF REVIEW

Inflammatory breast cancer (IBC) is the most fatal type presentation of clinical breast cancer. The immune tumor microenvironment (TME) of IBC is characterized by signals of immune evasion but suggests actionable vulnerability to immune-checkpoint inhibitors (ICIs). In this review, we aimed to summarize the most important preclinical evidences of IBC immune-vulnerability and the first data from clinical trials evaluating ICIs in IBC.

RECENT FINDINGS

IBC is characterized by a preexisting active immune TME suppressed by mechanisms of immune-escape, including inhibitory immune-checkpoints, whose expression is higher than in non-IBC. Clinical trials evaluating ICIs in patients with IBC are burdened by slow accrual and low enrollment.

SUMMARY

Because of the limited data from clinical trials, no conclusions about the activity of ICIs in IBC can be drawn. Ongoing clinical trials are assessing many promising ICI-based combination approaches. An enhanced multicenter collaboration to evaluate ICIs in patients with this aggressive form of disease and to improve clinical outcomes is required.

Early on-treatment transcriptional profiling as a tool for improving pathological response prediction in HER2-positive inflammatory breast cancer

Background

Inflammatory breast cancer (IBC) is a rare and understudied disease, with 40% of cases presenting with human epidermal growth factor receptor 2 (HER2)-positive subtype. The goals of this study were to (i) assess the pathologic complete response (pCR) rate of short-term neoadjuvant dual-HER2-blockade and paclitaxel, (ii) contrast baseline and on-treatment transcriptional profiles of IBC tumor biopsies associated with pCR, and (iii) identify biological pathways that may explain the effect of neoadjuvant therapy on tumor response.

Patients and Methods

A single-arm phase II trial of neoadjuvant trastuzumab (H), pertuzumab (P), and paclitaxel for 16 weeks was completed among patients with newly diagnosed HER2-positive IBC. Fresh-frozen tumor biopsies were obtained pretreatment (D1) and 8 days later (D8), following a single dose of HP, prior to adding paclitaxel. We performed RNA-sequencing on D1 and D8 tumor biopsies, identified genes associated with pCR using differential gene expression analysis, identified pathways associated with pCR using gene set enrichment and gene expression deconvolution methods, and compared the pCR predictive value of principal components derived from gene expression profiles by calculating and area under the curve for D1 and D8 subsets.

Results

Twenty-three participants were enrolled, of whom 21 completed surgery following neoadjuvant therapy. Paired longitudinal fresh-frozen tumor samples (D1 and D8) were obtained from all patients. Among the 21 patients who underwent surgery, the pCR and the 4-year disease-free survival were 48% (90% CI 0.29-0.67) and 90% (95% CI 66-97%), respectively. The transcriptional profile of D8 biopsies was found to be more predictive of pCR (AUC = 0.91, 95% CI: 0.7993-1) than the D1 biopsies (AUC = 0.79, 95% CI: 0.5905-0.9822).

Conclusions

In patients with HER2-positive IBC treated with neoadjuvant HP and paclitaxel for 16 weeks, gene expression patterns of tumor biopsies measured 1 week after treatment initiation not only offered different biological information but importantly served as a better predictor of pCR than baseline transcriptional analysis.

Trial Registration

ClinicalTrials.gov identifier: NCT01796197 (https://clinicaltrials.gov/ct2/show/NCT01796197); registered on February 21, 2013.

Trends, survival outcomes, and predictors of nonadherence to mastectomy guidelines for nonmetastatic inflammatory breast cancer

BACKGROUND

The Current National Comprehensive Cancer Network guidelines recommend modified radical mastectomy (MRM) as the surgical treatment of choice for nonmetastatic inflammatory breast cancer (IBC). Limited studies have looked into the outcomes of breast conserving surgery (BCS) vs. MRM for IBC.

METHODS

National Cancer Database (NCDB) data from 2004 to 2014 were retrospectively analyzed. Patients' demographics, tumor characteristics, and overall survival (OS) trends were compared for BCS and MRM cases of nonmetastatic IBC. Univariate and multivariate analyses were performed.

RESULTS

A total of 413 (3.89%) BCS and 10,197 (96.11%) MRM cases were identified. Median follow-up was 58.45 months. Compared to MRM, BCS patients were more likely to be older, be African American, have Medicare/Medicaid or be uninsured, live in lower education ZIP codes, and live in a metropolitan area (all p < 0.05). BCS rates significantly decreased from 5.84% in 2004 to 3.19% in 2014 (p < 0.001). BCS patients also were more likely to have less than 50% of the breast involved (51.57% vs. 43.88%; p = 0.0081) and were less likely to receive trimodal therapy (50.85% vs. 74.62%; p = <0.0001). The OS was significantly higher in the mastectomy group over 9 years at 62.02% vs. 54.47% in the BCS group. Additionally, in the adjusted multivariate model, BCS cases were associated with 23% higher hazards of overall mortality (p = 0.0091).

CONCLUSION

BCS was performed in a limited number of cases, which decreased over the study period. The analysis identified both demographic predictors of receiving BCS and significantly lower OS for IBC patients undergoing a BCS.

Toll-Like Receptor-Mediated Activation of CD39 Internalization in BMDCs Leads to Extracellular ATP Accumulation and Facilitates P2X7 Receptor Activation

Toll-like receptors (TLRs) trigger innate immune responses through their recognition of conserved molecular ligands of either endogenous or microbial origin. Although activation, function, and signaling pathways of TLRs were already well-studied, their precise function in specific cell types, especially innate immune cells, needs to be further clarified. In this study, we showed that when significantly decreased amounts of membrane CD39, an adenosine triphosphate (ATP)-degrading enzyme, were detected in lipopolysaccharide (LPS)-treated bone marrow-derived dendritic cells (BMDCs), Cd39 mRNA expression, and whole-cell CD39 expression were at the same levels as those in untreated BMDCs. Further experiments demonstrated that the downregulation of membrane CD39 expression in LPS-treated BMDCs was mediated by endocytosis, leading to membrane-exposed CD39 downregulation, which was positively associated with decreased enzymatic activity in ATP metabolism and increased extracellular ATP accumulation. The accumulated ATP promoted intracellular calcium accumulation and IL-1β production in BMDCs through P2X7 signaling activation. Further research revealed that not only LPS but also other TLR ligands, excluding polyI:C, induced CD39 internalization in BMDCs and that the MyD88 pathway was critical in this process. The results suggested that the activation of CD39 internalization in DCs induced by a TLR ligand caused increased ATP accumulation, leading to P2X7 receptor activation that mediated a proinflammatory effect. Considering the strong modulatory effect of extracellular ATP accumulation on the immune response and inflammation, the manipulation of membrane CD39 expression on DCs may have implications on the regulation and treatment of inflammatory responses.