Mutations inBRCA1andBRCA2high penetrance genes account for most hereditary breast and ovarian cancer, although other new high-moderate penetrance genes included in multigene panels have increased the genetic diagnosis of hereditary breast and ovarian cancer families by 50%. Multigene cancer panels provide new challenges related to increased frequency of variants of uncertain significance, new gene-specific cancer risk assessments, and clinical recommendations for carriers of mutations of new genes. Although clinical criteria for genetic testing continue to be largely based on personal and family history with around a 10% detection rate, broader criteria are being applied with a lower threshold for detecting mutations when there are therapeutic implications for patients with breast or ovarian cancer. In this regard, new models of genetic counselling and testing are being implemented following the registration of PARP inhibitors for individuals who display BRCA mutations. Massive sequencing techniques in tumor tissue is also driving a paradigm shift in genetic testing and potential identification of germline mutations. In this paper, we review the current clinical criteria for genetic testing, as well as surveillance recommendations in healthy carriers, risk reduction surgical options, and new treatment strategies in breast cancer gene-mutated carriers.

Breast cancer is the most common cancer in women in our country and it is usually diagnosed in the early and potentially curable stages. Nevertheless, around 20–30% of patients will relapse despite appropriate locoregional and systemic therapies. A better knowledge of this disease is improving our ability to select the most appropriate therapy for each patient with a recent diagnosis of an early stage breast cancer, minimizing unnecessary toxicities and improving long-term efficacy.

The Opti-HER HEART trial aimed to optimize activity while minimizing cardiac risk by combining trastuzumab, pertuzumab, and paclitaxel with non-pegylated liposomal doxorubicin in the treatment of HER2-positive early breast cancer. Patients with stage II–IIIB HER2-positive breast cancer received neoadjuvant trastuzumab, pertuzumab, paclitaxel, and a non-pegylated liposomal doxorubicin every three weeks for six cycles. The primary endpoint was cardiac safety during neoadjuvant therapy. Type A (symptomatic congestive heart failure) and B (asymptomatic reduction of left ventricular ejection fraction) cardiac events were evaluated. Secondary endpoints included the evaluation of the pathological complete response (pCR) rate and overall response rate, among others. As an ad-hoc exploratory analysis, the expression of 55 breast cancer-related genes, including the PAM50 genes, was measured in 58 baseline tumor samples and 60 surgical specimens. Eighty-three patients were recruited. The incidence of cardiac events during neoadjuvant treatment was 2.4%. No type A cardiac event was observed. The overall pCR rate was 56.6% (95% confidence interval (CI) 45.3–67.5%). The HER2-enriched subtype, which represented 52.0% of all baseline samples, was associated with a higher pCR rate compared to non-HER2-enriched tumors (83.3% vs. 46.3%; odds ratio 5.76, 95% CI 1.71–19.42). The association of subtype with pCR was independent of known clinicopathological variables, including hormone receptor status. Compared to baseline samples, surgical specimens showed a significant downregulation of proliferation-related genes (MKI67 and CCNB1) and ERBB2 levels, and a significant upregulation of luminal-related (ESR1 and PGR) and immune (CD8A) genes. The combination of dual HER2 blockade with trastuzumab and pertuzumab with paclitaxel and non-pegylated liposomal doxorubicin is associated with a low rate of cardiac events. The HER2-enriched subtype is associated with a high rate of pCR. clinicaltrials.gov, NCT01669239 , Registered 20 August 2012.

One of the most common side effects of cancer treatment is cardiovascular disease, which substantially impacts long-term survivor’s prognosis. Cardiotoxicity can be related with either a direct side effect of antitumor therapies or an accelerated development of cardiovascular diseases in the presence of preexisting risk factors. Even though it is widely recognized as an alarming clinical problem, scientific evidence is scarce in the management of these complications in cancer patients. Consequently, current recommendations are based on expert consensus. This Guideline represents SEOM’s ongoing commitment to progressing and improving supportive care for cancer patients.

Purpose: Tumor progression has been linked to stiffening of the extracellular matrix caused by fibrosis. Cancer cells can be mechanically conditioned by stiff extracellular matrix, exhibiting a 1,004-gene signature [mechanical conditioning (MeCo) score]. Nintedanib has demonstrated antifibrotic activity in idiopathic pulmonary fibrosis. This study explores nintedanib’s antifibrotic effect on breast cancer outcomes. Experimental Design: We present long-term follow-up and analysis of a neoadjuvant randomized phase II trial in early HER2-negative breast cancer. Patients (N = 130) underwent a baseline biopsy and received 12 paclitaxel courses alone (control arm) or in combination with nintedanib (experimental arm). The tumor MeCo score was determined by RNA sequencing. The primary aim was to assess nintedanib’s impact on event-free survival based on MeCo scores. Results: Follow-up data were retrieved from 111 patients; 75 baseline and 24 post-run-in phase samples were sequenced. After median follow-up of 9.67 years, median event-free survival was not statistically different between arms (P = 0.37). However, in the control arm, high- versus low-MeCo patients had a statistically higher relapse risk: HR = 0.21; P = 0.0075. This risk was corrected by nintedanib in the experimental arm: HR = 0.37; P = 0.16. Nintedanib demonstrated pharmacodynamic engagement, reducing the MeCo score by 25% during the run-in phase (P < 0.01). Patients with low MeCo after run-in had the best long-term prognosis (HR = 0.087; P = 0.03). Conclusions: High MeCo is predictive of poor outcomes in HER2-negative early breast cancer, although this risk can be mitigated by nintedanib, which is able to specifically reduce MeCo.