Emerging Role of Genomics and Cell-Free DNA in Breast Cancer

OPINION STATEMENT

Precision Medicine is gaining momentum as the future gold standard healthcare strategy as it enables treatment optimization and consequently a potential improvement for quality of life and survival. This paradigm shift was possible thanks to new high-throughput genomics technologies, which provide prognostic and predictive information on tumor biology and potential treatment options, as standard pathological procedures are unable to capture both spatial and temporal tumor heterogeneity. As a result of decreasing costs, both solid and liquid-based genomics have an increasingly important role in clinical trials' screening procedures and are gradually being incorporated into clinical practice. Notwithstanding the great potential, its clinical utility is still a matter of debate and clinicians need to be aware of caveats in interpreting resulting data.

Role of anthracyclines in neoadjuvant anti-HER2 regimens for HER2+ breast cancer (BC): A network meta-analysis (NMA)

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Background: It is matter of current debate which would be the best chemotherapy backbone of neoadjuvant HER2-targeted therapy for HER2+ BC. The TRAIN 2 trial showed no significant difference in terms of pathological complete response (pCR) when anthracyclines–based (CTA) or anthracyclines–free regimens (CT) were combined with dual HER2 blockade. However, it remains unclear how anthracyclines may influence the relative benefit across different anti-HER2 treatments. Methods: A systematic review was conducted which included all phase II/III randomized clinical trials (RCTs) comparing different neoadjuvant regimens for HER2+ BC. pCR (yT0/isN0) was the outcome of interest. Indirect comparisons of all combination of anti-HER2 agents with CTA or CT were estimated with a random-effects frequentist NMA. Estimated pCR rates were inferred adopting a Bayesian NMA. Results: 17 RCTs (3933 patients) were included. Overall, 8 arms were identified, comprising all possible combinations of CTA and CT with trastuzumab (H), lapatinib (L) and dual HER2 blockade (D) but also CTA and D only. Odds ratios (OR) for pCR and 95% confidence interval (CI) of selected NMA comparisons are shown in the table. Estimated rates of pCR for each treatment and 95% credible interval (CrI) are reported in the table. Conclusions: Through indirect comparisons, no significant pCR gain was found for CTA vs CT when combined to D, H and L. In particular, considering double vs single-agent anti-HER2 regimens, D-CT remains superior to H-CTA, supporting a possible omission of anthracyclines when dual anti-HER2 block is used. On the contrary, our pooled estimate suggests a more relevant role for anthracyclines when comparing H-CT/A vs CTA. Moreover, we estimated a 4% pCR gain for D-CTA vs D-CT, and an 8% higher pCR rate for H-CTA vs H-CT. [Table: see text]

Bevacizumab or PARP-inhibitors maintenance therapy for platinum-sensitive (PS) recurrent ovarian cancer (rOC)? A network meta-analysis (NMA)

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Background: Patients (pts) experiencing a PS rOC are generally re-exposed to a platinum based-chemotherapy (CT). In this setting, the addition of a targeted agent like bevacizumab (BEV) or PARP inhibitors (PARPi) as concomitant and/or maintenance therapy has shown to improve progression free survival (PFS). In the absence of direct comparison in randomized trials (RCTs), we have performed a NMA to evaluate differences in terms of efficacy between BEV and PARPi in pts with PS rOC, according to BRCA status. Methods: We searched PubMed, Embase and Medline for RCTs involving pts with PS rOC treated with BEV (n = 3, 1563 pts) or PARPi (n = 5, 1839 pts). Only trials with PFS as primary endpoint were included. Trials in first line setting were excluded. Analyses have been done pooling pts who had received PARPi in three groups, according to the available data on BRCA genes status: all comers (AC), BRCA mutated pts (BRCAm) and BRCA wild-type pts (BRCAwt). A frequentist approach has been used with R statistical software. To rank the effect size of treatments, surface under the cumulative ranking value (SUCRA) has been applied. Results: In AC pts, PARPi improved PFS compared to BEV (hazard ratio [HR] = 0.70, 95% CI 0.54-0.91, test of heterogeneity [I2] = 40.5%). In BRCAm pts the gain in PFS for PARPi was even higher compared to BEV (HR = 0.46, 95% CI 0.36-0.59, I2= 17.2%). In BRCAwt pts the benefit of PARPi over BEV was not statistically significant (HR = 0.87, 95% CI 0.63-1.20, I2= 35.7%) but PARPi had the highest likelihood of being ranked as the best treatment in terms of efficacy according to SUCRA (90% and 60%, respectively for PARPi and BEV). Hazard ratio for PFS between PARPi, BEV and CT in the three cohorts are reported in the table. Conclusions: According to indirect comparisons, PARPi performed the best for the treatment of PS rOC, especially in BRCAm pts who had not previously received PARPi. BEV could be still an option in BRCAwt pts. [Table: see text]

Circulating tumor DNA analysis in breast cancer: Is it ready for prime-time?

Precision Medicine is becoming the new paradigm in healthcare as it enables better resources allocation, treatment optimization with a potential side-effects reduction and consequent impact on quality of life and survival. This revolution is being catalyzed by liquid biopsy technologies, which provide prognostic and predictive information for advanced cancer patients, without the analytical and procedural drawbacks of tissue-biopsy. In particular, circulating tumor DNA (ctDNA) is gaining momentum as a clinically feasible option capable to capture both spatial and temporal tumor heterogeneity. Several techniques are currently available for ctDNA extraction and analysis, each with its preferential case scenarios and preanalytical implications which must be taken into consideration to effectively support clinical decision-making and to better highlight its clinical utility. Aim of this review is to summarize both analytical developments and clinical evidences to offer a comprehensive update on the deployment of ctDNA in breast cancer's (BC) characterization and treatment.