The therascreen PIK3CA mutation assay and the alpha-specific PI3K inhibitor alpelisib are FDA-approved for identifying and treating patients with advanced PIK3CA-mutated (PIK3CAmut) breast cancer ...(BC). However, it is currently unknown to what extend this assay detects most PIK3CA mutations in BC. This information is critical as patients and clinicians are using this and other genomic assays to indicate alpelisib.
Data from 6338 patients with BC was explored across 10 publicly available studies. The primary objective was to evaluate the proportion and distribution of PIK3CA mutations in BC. Secondary objectives were (1) to evaluate in silico the spectrum of PIK3CA mutations in BC that would be captured by the therascreen panel; (2) to evaluate the proportion and distribution of PIK3CA mutations in hormone receptor-positive/HER2-negative (HR+/HER2-), HER2+, and triple-negative BC (TNBC); and (3) to explore the identification of PIK3CA mutations in a cohort of 48 HR+/HER2- advanced BC patients by the Guardant B360 circulating tumor DNA (ctDNA) assay.
Patients with PIK3CAmut tumors represented 35.7% (2261/6338). Five PIK3CA mutations comprised 73% of all PIK3CA mutations: H1047R (35%), E545K (17%), E542K (11%), N345K (6%), and H1047L (4%). Therascreen gene list would capture 72% of all PIK3CA mutations and 80% of patients with a known PIK3CAmut BC. Among patients with double PIK3CAmut tumors (12% of all PIK3CAmut), the therascreen panel would capture 78% as harboring 1 single PIK3CA mutation, 17% as PIK3CAmut undetected, and 5% as PIK3CA double-mut. PIK3CA mutation rates were lower in TNBC (16%) compared to HR+/HER2 (42%) and HER2+ (31%) BC; however, the distribution of the 4 main PIK3CA mutations across subtypes was similar. Finally, 28% of PIK3CA mutations identified in ctDNA in 48 patients with advanced HR+/HER2- BC were not part of the therascreen panel.
PIK3CA mutations in BC are heterogenous and ~ 20% of patients with a known PIK3CA mutation, and 95% with a known double PIK3CAmut tumor, would not be captured by the therascreen panel. Finally, the clinical utility of PIK3CA mutations not present in the therascreen companion diagnostic assay or identified by other sequencing-based assays needs further investigation.
The novel coronavirus disease 2019 (COVID-19) shows a wide spectrum of clinical presentations, severity, and fatality rates. The reason older patients and males show increased risk of severe disease ...and death remains uncertain. Sex hormones, such as estradiol, progesterone, and testosterone, might be implicated in the age-dependent and sex-specific severity of COVID-19. High testosterone levels could upregulate transmembrane serine protease 2 (TMPRSS2), facilitating the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into host cells via angiotensin-converting enzyme 2 (ACE2). Data from patients with prostate cancer treated with androgen-deprivation therapy seem to confirm this hypothesis. Clinical studies on TMPRSS2 inhibitors, such as camostat, nafamostat, and bromhexine, are ongoing. Antiandrogens, such as bicalutamide and enzalutamide, are also under investigation. Conversely, other studies suggest that the immune modulating properties of androgens could protect from the unfavorable cytokine storm, and that low testosterone levels might be associated with a worse prognosis in patients with COVID-19. Some evidence also supports the notion that estrogens and progesterone might exert a protective effect on females, through direct antiviral activity or immune-mediated mechanisms, thus explaining the higher COVID-19 severity in post-menopausal women. In this perspective, we discuss the available evidence on sex hormones and hormone therapy in patients infected with SARS-CoV-2, and we highlight the possible implications for cancer patients, who can receive hormonal therapies during their treatment plans.
Adjuvant chemotherapy is the standard of care in high-risk early breast cancer patients. Dose-dense should be the preferred schedule of administration. However, its long-term benefit is unknown.
In ...the Italian multicentre Phase 3 randomised MIG-1 trial, node-positive and high-risk node- negative breast cancer patients were randomised to receive six cycles of adjuvant fluorouracil, epirubicin and cyclophosphamide regimen administered every 3 (FEC21) or 2 (FEC14) weeks. The primary endpoint was overall survival (OS), and the secondary endpoint was event-free survival (EFS).
From 1992 to 1997, 1214 patients were included. Median follow-up was 15.8 years. In all, 15-year OS was 71% and 68% in the FEC14 and FEC21 groups, respectively (HR = 0.89; p = 0.25). In all, 15-year EFS was 47% and 43% in the FEC14 and FEC21 groups, respectively (HR = 0.87; p = 0.18). In a pre-planned subgroup analysis, among patients with hormone receptor-negative tumours, 15-year OS was 70% and 65% in the FEC14 and FEC21 groups, respectively (HR = 0.73; 95% CI: 0.51-1.06); 15-year EFS was 58% and 43% in the FEC14 and FEC21 groups, respectively (HR = 0.70; 95% CI: 0.51-0.96).
Updated results from the MIG-1 study are numerically in favour of dose-dense chemotherapy, and suggest a long-term benefit of this approach in high-risk early breast cancer patients.
The diagnosis of breast cancer during pregnancy represents a challenging situation for the patient, her caregivers and physicians. Pregnancy adds complexity to oncological treatment planning, as many ...therapies can be potentially dangerous to the fetus. Therefore, a multidisciplinary approach is needed to offer a proper care for obtaining the best possible outcomes for the mother and the future child. Breast surgery is feasible throughout the pregnancy while radiotherapy should be postponed after delivery. Administration of chemotherapy is considered safe and can be given during the second and third trimesters, while it is contraindicated in the first trimester due to the high risk of fetal malformations. Endocrine therapy and targeted agents are not recommended during the whole pregnancy period; however, limited data are available on the use of the majority of new anticancer drugs in this context. The aim of the current review is to provide an update on the current state of art about the management of women diagnosed with breast cancer during pregnancy.
Background
CDK4/6 inhibitors (CDKi), namely, palbociclib, ribociclib, and abemaciclib, combined with either an aromatase inhibitor (AI) or fulvestrant are the standard first/second line for hormone ...receptor-positive(HR+)/HER2-negative(neg) metastatic breast cancer (MBC). However, the choice of one specific CDKi is arbitrary and based on the physician’s experience with the drug, toxicity profile, and patient’s preferences, whereas biomarkers for optimal patient selection have not been established so far. Moreover, upfront chemotherapy is still recommended in case of clinical presentation with visceral crisis, despite no evidence of superior benefit for chemotherapy regimens against CDKi-based regimens. Recent correlative biomarker analyses from pivotal trials of palbociclib and ribociclib showed that HR+/HER2-neg MBC might respond differently according to the molecular intrinsic subtype, with Luminal A and B tumors being sensitive to both CDKi, Basal-like being insensitive to endocrine therapy, irrespective of CDKi, and HER2-enriched tumors showing a benefit only with ribociclib-based therapy.
Clinical case
We hereby present a paradigmatic clinical case of a woman affected by a relapsed HR+/HER2-neg MBC with bone and nodal lesions, presenting with a visceral crisis in the form of lymphangitis carcinomatosis and diagnosed with a molecularly HER2-enriched tumor, successfully treated with upfront ribociclib + fulvestrant. The patient experienced a complete symptomatic and radiologic remission of the lymphangitis with a partial response as best response, according to RECIST 1.1 criteria. The progression-free survival (PFS) was of 20 months, in line with the median PFS observed in the ribociclib + fulvestrant pivotal trial, where, however, patients with visceral crisis had been excluded.
Conclusions
This clinical case confirms in the real-world setting that non-luminal subtypes can be found in HR+/HER2-neg disease and may have potential therapeutic implications in the metastatic setting. It also questions the recommendation of upfront chemotherapy in the case of a visceral crisis in the era of CDKi-based regimens. These issues merit further evaluation in prospective and larger studies.
A precise assessment of the efficacy of first-/second-line endocrine therapies (ET) ± target therapies (TT) in clinically-relevant subgroups of hormone receptor-positive (HR+)/HER2-negative ...metastatic breast cancer (MBC) has not yet been conducted. To improve our current knowledge and support clinical decision-making, we thus conducted a systematic literature search to identify all first-/second-line phase II/III randomized clinical trials (RCT) of currently approved or most promising ET ± TT. Then, we performed a meta-analysis to assess progression-free (PFS) and/or overall survival (OS) benefit in several clinically-relevant prespecified subgroups. Thirty-five RCT were included (17,595 patients). Pooled results show significant reductions in the risk of relapse or death of 26-41% and 12-27%, respectively, depending on the clinical subgroup. Combination strategies proved to be more effective than single-agent ET (PFS hazard ratio (HR) range for combinations: 0.60-0.65 vs. HR range for single agent ET: 0.59-1.37; OS HR range for combinations: 0.74-0.87 vs. HR range for single agent ET: 0.68-0.98), with CDK4/6-inhibitors(i) + ET being the most effective regimen. Single agent ET showed comparable efficacy with ET+TT combinations in non-visceral (
= 0.63) and endocrine sensitive disease (
= 0.79), while mTORi-based combinations proved to be a valid therapeutic option in endocrine-resistant tumors, as well as PI3Ki + ET in PIK3CA-mutant tumors. These results strengthen international treatment guidelines and can aid therapeutic decision-making.
In the absence of identified therapeutic targets, chemotherapy is the main systemic treatment option for triple-negative breast cancer (TNBC). The achievement of a pathological complete response ...(pCR) after neoadjuvant chemotherapy leads to good outcome, whereas patients not achieving a pCR are at high risk of relapse. Various trials have evaluated the inclusion of platinum in neoadjuvant chemotherapy regimens for TNBC, leading to non-univocal results. The panel of the Italian Association of Medical Oncology (AIOM) Guidelines on Breast Cancer developed a clinical recommendation on the addition of platinum to anthracycline/taxane-based neoadjuvant chemotherapy for TNBC by using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology and the Evidence to Decision framework (EtD). Five studies were eligible. The panel identified the following outcomes of benefit: pCR (critical), disease/event-free survival (DFS/EFS, critical), and overall survival (OS, critical). The panel identified febrile neutropenia (critical), serious adverse events (critical), anemia grade 3-4 (important), thrombocytopenia grade 3-4 (important) as outcomes of harms. The probability of pCR was higher in the platinum-based chemotherapy group versus control group (RR = 1.45, 95%CI 1.28-1.64); however, no impact on long-term outcome was observed. Neoadjuvant treatment regimens containing platinum resulted in a non-significant increase in the risk of febrile neutropenia and in a significant increase in the risk serious adverse events, G3-G4 anemia and G3-G4 thrombocytopenia: 11.3% versus 0.8%, RR = 15.66 (95%CI 6.38-38.44). The panel judged uncertain/favorable the benefit/harms balance. The panel's final recommendation was conditional in favor of the inclusion of platinum in anthracycline/taxane-based neoadjuvant regimens for TNBC.
Circulating tumor DNA (ctDNA) levels may predict response to anticancer drugs, including CDK4/6 inhibitors and endocrine therapy combinations (CDK4/6i+ET); however, critical questions remain ...unanswered such as which assay or statistical method to use. Here, we obtained paired plasma samples at baseline and week 4 in 45 consecutive patients with advanced breast cancer treated with CDK4/6i+ET. ctDNA was detected in 96% of cases using the 74-gene Guardant360 assay. A variant allele fraction ratio (VAFR) was calculated for each of the 79 detected mutations between both timepoints. Mean of all VAFRs (mVAFR) was computed for each patient. In our dataset, mVAFR was significantly associated with progression-free survival (PFS). Baseline VAF, on-treatment VAF or absolute changes in VAF were not associated with PFS, nor were CA-15.3 levels at baseline, week 4 or the CA-15.3 ratio. These findings demonstrate that ctDNA dynamics using a standardized multi-gene panel and a unique methodological approach predicts treatment outcome. Clinical trials in patients with an unfavorable ctDNA response are needed.
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