Reviewing the risk of breast cancer recurrence following breast reconstruction.

BACKGROUND: It is widely accepted that both autologous and alloplastic reconstruction are safe. A recent publication reported a significant association between textured implants and metastatic recurrence of breast cancer. This study aims to assess if the published results are reproducible in our cohort and to review the safety of breast reconstruction. METHODS: This is a retrospective cohort study of adult patients undergoing mastectomy and either alloplastic or autologous breast reconstruction at a single quaternary hospital. Outcomes include disease free survival (DFS), local and recurrence free survival (LRRFS) and BIA-ALCL. For time to event endpoints, unadjusted and multivariate adjusted hazard ratios (HRs) were estimated using Cox regression, and penalized Cox regression respectively. RESULTS: Four hundred and twenty-six patients of whom 187 underwent autologous reconstruction and 239 underwent alloplastic. There were 43 cancer recurrences (24 alloplastic and 19 autologous) and 14 local regional recurrences (8 alloplastic and 4 autologous). There were 26 deaths and no instances of BIA-ALCL. Median follow-up time was 4.7 years. No evidence of association was found between breast reconstruction method and DFS (HR 0.87 CI: 0.47-1.58). It is uncertain whether implant texture grade was associated with increased breast cancer recurrence (HR 2.17 CI: 0.65-7.52). CONCLUSION: Both autologous and alloplastic breast reconstruction have been carried out in our cohort and reconstructive modality was not associated with either reduced DFS or LRRFS. The results in this cohort show there is uncertainty between the use of textured breast implants and either local or distant breast cancer recurrence.

Publisher Correction: Single-cell profiling of breast cancer T cells reveals a tissue-resident memory subset associated with improved prognosis.

In the version of this article originally published, the institution in affiliation 10 was missing. Affiliation 10 was originally listed as Department of Surgery, Royal Melbourne Hospital and Royal Womens' Hospital, Melbourne, Victoria, Australia. It should have been Department of Surgery, Royal Melbourne Hospital and Royal Womens' Hospital, University of Melbourne, Melbourne, Victoria, Australia. The error has been corrected in the HTML and PDF versions of this article.

Single-cell profiling of breast cancer T cells reveals a tissue-resident memory subset associated with improved prognosis.

The quantity of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is a robust prognostic factor for improved patient survival, particularly in triple-negative and HER2-overexpressing BC subtypes1. Although T cells are the predominant TIL population2, the relationship between quantitative and qualitative differences in T cell subpopulations and patient prognosis remains unknown. We performed single-cell RNA sequencing (scRNA-seq) of 6,311 T cells isolated from human BCs and show that significant heterogeneity exists in the infiltrating T cell population. We demonstrate that BCs with a high number of TILs contained CD8+ T cells with features of tissue-resident memory T (TRM) cell differentiation and that these CD8+ TRM cells expressed high levels of immune checkpoint molecules and effector proteins. A CD8+ TRM gene signature developed from the scRNA-seq data was significantly associated with improved patient survival in early-stage triple-negative breast cancer (TNBC) and provided better prognostication than CD8 expression alone. Our data suggest that CD8+ TRM cells contribute to BC immunosurveillance and are the key targets of modulation by immune checkpoint inhibition. Further understanding of the development, maintenance and regulation of TRM cells will be crucial for successful immunotherapeutic development in BC.

Breast Tissue Composition and Immunophenotype and Its Relationship with Mammographic Density in Women at High Risk of Breast Cancer.

AIM: To investigate the cellular and immunophenotypic basis of mammographic density in women at high risk of breast cancer. METHODS: Mammograms and targeted breast biopsies were accrued from 24 women at high risk of breast cancer. Mammographic density was classified into Wolfe categories and ranked by increasing density. The histological composition and immunophenotypic profile were quantified from digitized haematoxylin and eosin-stained and immunohistochemically-stained (ERα, ERß, PgR, HER2, Ki-67, and CD31) slides and correlated to mammographic density. RESULTS: Increasing mammographic density was significantly correlated with increased fibrous stroma proportion (rs (22) = 0.5226, p = 0.0088) and significantly inversely associated with adipose tissue proportion (rs (22) = -0.5409, p = 0.0064). Contrary to previous reports, stromal expression of ERα was common (19/20 cases, 95%). There was significantly higher stromal PgR expression in mammographically-dense breasts (p=0.026). CONCLUSIONS: The proportion of stroma and fat underlies mammographic density in women at high risk of breast cancer. Increased expression of PgR in the stroma of mammographically dense breasts and frequent and unexpected presence of stromal ERα expression raises the possibility that hormone receptor expression in breast stroma may have a role in mediating the effects of exogenous hormonal therapy on mammographic density.