Survival outcomes seen with neoadjuvant chemotherapy in the management of locally advanced inflammatory breast cancer (IBC) versus matched controls.

Inflammatory breast cancer (IBC) poses an ongoing challenge as rates of disease recurrence and mortality remain high compared to stage-matched controls. However, frontline therapy has evolved through the years, including the widespread use of neoadjuvant chemotherapy (NAC) given the prognostic importance of pathologic complete response (pCR). Due to these sweeping changes, we need new data to assess current recurrence and survival outcomes for locally advanced IBC in the context of matched non-inflammatory controls. We conducted a retrospective analysis of institutional IBC data from 2010 to 2016 with the primary objective of comparing overall survival (OS), relapse-free survival (RFS), and distant relapse-free survival (DRFS). We matched IBC patients to non-inflammatory controls based on age, receptor status, tumor grade, clinical stage, and receipt of prior NAC. Secondary objectives included assessing pCR rates and identifying prognostic factors. Among NAC recipients, we observed similar pCR rates (47.6 % vs. 49.4 %, p = 0.88) between IBC (n = 84) and matched non-IBC (n = 81) cohorts. However, we noted a significant worsening of OS (p = 0.0001), RFS (p = 0.0001), and DRFS (p = 0.001) in the IBC group. Specifically, 5-year OS in the IBC cohort was 58.9 % vs. 86.7 % for matched controls (p = 0.0003). Older age was a weak negative predictor for OS (HR 1.03, p = 0.001) and RFS (HR 1.02, p = 0.01). For DRFS, older age was also a weak negative predictor (HR 1.02, p = 0.02), whereas the use of NAC was a positive predictor (HR 0.47, p = 0.02). Despite no clear difference in pCR, survival outcomes remain poor for IBC compared to matched non-inflammatory controls.

Treatment of small (T1mic, T1a, and T1b) node-negative HER2+ breast cancer - a review of current evidence for and against the use of anti-HER2 treatment regimens.

INTRODUCTION: Since the advent of anti-HER2 therapies, evidence surrounding adjuvant treatment of small (T1mic, T1a, and T1b), node-negative, HER2-positive breast cancer (HER2+ BC) has remained limited. Practices vary widely between institutions with little known regarding the added benefit of systemic therapy, including cytotoxic chemotherapy and HER2-directed treatments. Our group has set out to perform an extensive review of available literature on this topic. AREAS COVERED: In this review, we examined HER2 biology, anti-HER therapies, outcome definitions, and available prospective and retrospective data surrounding the use of adjuvant therapy in those with small, node-negative, HER2+ BC. For outcomes, we primarily explored breast cancer-specific survival (BCSS), invasive disease-free survival (iDFS), and overall survival (OS). We also investigated the incidence of adverse events with a particular focus on symptomatic and asymptomatic declines in ejection fraction. EXPERT OPINION: Retrospective data will likely be the main driver for future treatment decisions. Given what we know, high-risk T1b and T1c subgroups derive measurable added benefit from HER2-guided combination therapies but it's not clear whether these benefits outweigh known risks associated with this combination therapy. For tumors ≤0.5 cm (T1mic and T1a), treatment remains highly controversial with limited evidence available through retrospective analysis that suggest over-treatment may be occurring.