Endocrine therapy for early breast cancer in the era of oral selective estrogen receptor degraders: challenges and future perspectives.

PURPOSE OF REVIEW: Growth and survival of hormone receptor positive breast cancer cells are dependent on circulating hormones (e.g., estrogen and progesterone). Endocrine therapy improved outcomes in both early and advanced hormone receptor positive breast cancer. These treatments include drugs with different mechanisms of action, namely selective estrogen receptor modulators (SERM), aromatase inhibitors, and selective estrogen receptor degraders (SERDs). SERDs represent estrogen receptor antagonists, favoring its degradation and thus interfering with proliferation genes transcription and activation. Fulvestrant is the first approved SERD, administered intramuscularly for treating advanced breast cancer. RECENT FINDINGS: Oral SERDs have been tested to overcome the limitation of the intramuscular administration, and to increase SERD bioavailability. Recently, an oral SERD, Elacestrant, has been approved by the Food and Drug Administration (FDA) for patients carrying an ESR1 mutation. In fact, oral SERDs seem to be effective in tumors harboring ESR1 mutations, a well known mechanism of resistance to endocrine therapy (especially aromatase inhibitors). SUMMARY: More recently, oral SERDs have been tested in patients with early hormone receptor positive breast cancer, although their impact on survival and in this curative setting compared to standard endocrine therapy still needs to be elucidated. The best timing and duration of SERD administration and specific biomarkers in (neo)adjuvant setting remain largely unknown.

Clinical utility of genomic signatures for the management of early and metastatic triple-negative breast cancer.

PURPOSE OF REVIEW: This comprehensive review aims to provide timely and relevant insights into the current therapeutic landscape for triple-negative breast cancer (TNBC) and the molecular features underlying this subtype. It emphasizes the need for more reliable biomarkers to refine prognostication and optimize therapy, considering the aggressive nature of TNBC and its limited targeted treatment options. RECENT FINDINGS: The review explores the multidisciplinary management of early TNBC, which typically involves systemic chemotherapy, surgery, and radiotherapy. It highlights the emergence of immune checkpoint inhibitors (ICIs), poly(ADP-ribose) polymerase (PARP) inhibitors, and antibody-drug conjugates (ADCs) as promising therapeutic strategies for TNBC. Recent clinical trials investigating the use of ICIs in combination with chemotherapy and the approval of pembrolizumab and atezolizumab for PD-L1-positive metastatic TNBC are discussed. The efficacy of PARP inhibitors and ADCs in treating TNBC patients with specific genetic alterations is also highlighted. SUMMARY: The findings discussed in this review have significant implications for clinical practice and research in TNBC. The identification of distinct molecular subtypes through gene expression profiling has enabled a better understanding of TNBC heterogeneity and its clinical implications. This knowledge has the potential to guide treatment decisions, as different subtypes display varying responses to neoadjuvant chemotherapy. Furthermore, the review emphasizes the importance of developing reliable genomic and transcriptomic signatures as biomarkers to refine patient prognostication and optimize therapy selection in TNBC. Integrating these signatures into clinical practice may lead to more personalized treatment approaches, improving outcomes for TNBC patients.

Developing combination therapies with biologics in triple-negative breast cancer.

INTRODUCTION: Novel compounds have entered the triple-negative breast cancer (TNBC) treatment algorithm, namely immune checkpoints inhibitors (ICIs), PARP inhibitors and antibody-drug conjugates (ADCs). The optimization of treatment efficacy can be enhanced with the use of combination treatments, and the incorporation of novel compounds. In this review, we discuss the combination treatments under development for the treatment of TNBC. AREAS COVERED: The development of new drugs occurring in recent years has boosted the research for novel combinations to target TNBC heterogeneity and improve outcomes. ICIs, ADCs, tyrosine kinase inhibitors (TKIs), and PARP inhibitors have emerged as leading players in this new landscape, while other compounds like novel intracellular pathways inhibitors or cancer vaccines are drawing more and more interest. The future of TNBC is outlined in combination approaches, and based on new cancer targets, including many chemotherapy-free treatments. EXPERT OPINION: A large number of TNBC therapies have either proved clinically ineffective or weighted by unacceptable safety profiles. Others, however, have provided promising results and are currently in late-stage clinical trials, while a few have actually changed clinical practice in recent years. As novel, more and more selective drugs come up, combination strategies focusing the concept of synergy are fully warranted for the future.

Primary malignant phyllodes tumors of the breast: A retrospective analysis from a referral center.

BACKGROUND: The treatment for primary malignant phyllodes tumors of the breast (B-MPT) consists of wide local excision with negative margins (≥1 cm). However, because of their rarity, prognostic factors, type of surgery and adjuvant treatments are still a matter of debate. METHODS: We conducted a single-center retrospective study to describe outcomes and prognostic factors of patients with primary B-MPT, who underwent breast surgery from January 2000 to December 2021. The primary endpoint was the cumulative incidence of any recurrence. Secondary endpoints were the cumulative incidences of distant and local recurrences. RESULTS: 131 patients were included, of whom all received surgery, 5 adjuvant anthracycline-based chemotherapy and 15 radiation therapy. After a median follow-up of 6.4 years, the cumulative incidences at 5-years of any, local and distant recurrences were of 26% (95% Confidence Interval [CI], 4-34%), 16% (95%CI, 10-24%) and 10% (95%CI, 5.3-16%), respectively. Tumor size ≥ 5 cm was associated with higher distant recurrences (p = 0.05); instead, among small tumors (<5 cm), distant recurrences were higher in those with heterologous differentiation and/or multifocal disease (p = 0.06). Type of breast surgery (mastectomy vs. lumpectomy/excision) was not found to be significantly associated with distant (p = 0.32) or local (p = 0.17) recurrence, even after controlling local recurrence incidence for negative pathologic prognostic factors (p = 0.17). CONCLUSIONS: The natural history of B-MPT is burdened by local and distant recurrences. Pathologic prognostic factors (i.e., tumor size, heterologous differentiation and multifocal disease) more than the type of wide breast surgery (mastectomy vs. lumpectomy) seem to represent the most significant prognostic factor for recurrences.

Risk of thromboembolic events in patients with metastatic solid tumors treated with PARP inhibitors: A systematic review and meta-analysis of phase 3 randomized controlled trials.

BACKGROUND AND SCOPE: Poly(ADP-ribose) polymerase inhibitors (PARPi) have revolutionized cancer treatment in recent years. These drugs present a favorable safety profile, even though the potential risk of thromboembolic events (TEs) during their use has not been addressed yet. In addition, PARPi have been involved in an active scientific debate regarding non-oncologic indications, particularly during the Coronavirus Disease 2019 pandemic, including potential anti-thromboembolic effect. METHODS: To clarify whether patients treated with PARPi for metastatic solid tumors are either at increased or decreased risk of TEs, we conducted a systematic review of the literature and meta-analysis, including all phase 3 randomized controlled trials (RCTs) which investigated PARPi in this setting. Search was conducted through Medline, EMBASE, Pubmed, SCOPUS and Google Scholar in February 2023, including the proceedings of the principal oncology meetings of the last 10 years, with no time restriction. For each included study, frequencies of TEs in experimental and control arm were collected. RESULTS: Our search identified 2,369 reports, of which 20 were lastly selected. A total of 4,946 patients were included, across 12 different RCTs. The meta-analysis did not demonstrate either an increased or a reduced risk in TEs in patients treated with PARPi for metastatic disease (OR 1.50, range: 1.00-2.24; 95% CI; P = 0.050), with low heterogeneity and low publication bias. CONCLUSION: Although our research did not confirm either increased or decreased risk of TEs for PARPi use, no safety alerts emerged. Thromboembolic risk assessment models should always be integrated in daily clinical routine, to identify high-risk patients.