HER2 overexpression a major risk factor for recurrence in pT1a‐bN0M0 breast cancer: results from a French regional cohort

Abstract

The management of pT1a-bN0M0 breast cancer remains an area of controversy. Data from 714 patients classified as having pT1a-bN0M0 breast cancer and treated, from 1999 to 2004 in the Languedoc-Roussillon France, were analyzed. The human epidermal growth factor receptor 2 (HER2) status analyses were centralized. The objective of this study was to describe the prognosis of pT1a-bN0M0 breast cancer according to HER2 distribution and hormonal status. The median follow-up was 6.4 years. Ten-year overall survival was 94%. HER2 overexpression was observed in 6.1% of the patients. The 10-year prognosis of patients with HER2-positive tumors was worse than that of those with HER2-negative (disease-free survival 73% vs. 89%, P < 0.0001). Tumor size (T1a/T1b) was not a relevant prognostic factor. The co-expression of HER2 with hormonal receptors (HR) was associated with high recurrence at 10 years. In both univariate and multivariate analyses, the most relevant prognostic factor for this population was HER2 amplification. In multivariate analysis, patients with HER2-positive tumors had higher risk of mortality (HR, 3.89; 95% CI, 1.58–9.56). In pT1a-bN0M0 breast cancers, HER2 amplification or overexpression is a risk factor for recurrence. In HER2-positive breast cancers, HR expression is associated with a poor prognosis despite the hormone therapy. For this population, a personalized management may be required.

Do T1a breast cancers profit from adjuvant systemic therapy? A multicenter retrospective cohort study of 325 T1a-patients

“…In recent years there is increasing evidence that it is not only the tumor size itself but also biological features which are predictive for the outcome of patients, especially for T1a/b breast cancers. Factors like HER2-overexpression or negative hormone receptor (HR) status seem to have more impact on the prognosis of the patients than tumor size [8][9][10][11][12]. Until recently, it was generally accepted that especially T1a breast cancers do not require adjuvant systemic therapy.…”

Recent Progress in HER2 Associated Breast Cancer

“…Recently, from a French regional cohort, HER2 over-expression is proved to be a major risk factor for recurrence in pT1a-bN0M0 breast cancer (Rouanet et al, 2014). Also, HER2 over-expression was associated with locoregional recurrence (LRR) in the pre-adjuvant trastuzumab era (Lanning et al, 2015).…”

Systemic therapy for early‐stage HER2‐positive breast cancers: Time for a less‐is‐more approach?

“…Some retrospective analyses of patients with small HER2‐positive cancers have demonstrated worse outcomes compared with those achieved in patients with other breast cancer subtypes . In contrast, the results of other studies have indicated that outcomes are more favorable, with low recurrence rates reported in patients with small HER2‐positive breast cancers.…”

“…Several retrospective analyses have demonstrated that patients with small HER2‐positive breast cancers have inferior outcomes compared with those of patients with other breast cancer subtypes. However, recent data have challenged this concept and demonstrated favorable outcomes for patients with small HER2‐positive breast cancers (Table ) …”

“…A retrospective analysis of 960 patients with stage I tumors demonstrated that HER2‐positive status is a significant negative prognostic factor affecting 1‐year disease‐free survival (DFS) . Rouanet et al evaluated the prognosis of patients with T1a‐bN0 breast cancers according to HER2 and HR status and noted that the 10‐year DFS rate was significantly lower in the HER2‐positive group compared with the HER2‐negative group. The worse prognosis associated with HER2 status did not differ among patients with HR‐positive tumors, who had a poor prognosis regardless whether they received endocrine therapy.…”