Does the Sequence of Anthracycline and Taxane Matter? The NeoSAMBA Trial

A Comprehensive Review of Taxane Treatment in Breast Cancer: Clinical Perspectives and Toxicity Profiles

Taxanes, such as paclitaxel and docetaxel, have transformed the landscape of breast cancer treatment, playing pivotal roles in chemotherapy protocols for both early-stage and advanced/metastatic diseases. While these agents have demonstrated remarkable efficacy in enhancing patient outcomes, they are also linked to a range of adverse effects that can impact treatment tolerability and quality of life. This comprehensive review offers an in-depth exploration of taxane therapy in breast cancer, with a focus on clinical perspectives and toxicity profiles. We delineate the mechanisms of action of taxanes, their clinical effectiveness across various breast cancer subtypes, and the prevalent adverse effects encountered in clinical practice. Moreover, we deliberate on strategies for mitigating taxane-associated toxicity and optimizing treatment selection and sequencing based on individual patient characteristics and therapeutic objectives. Finally, we underscore areas for future research and advancement, encompassing the development of novel formulations, the identification of predictive biomarkers for treatment response, and the exploration of combination therapies to bolster therapeutic outcomes. By amalgamating existing evidence and clinical insights, this review aims to apprise clinicians and researchers of the current status of taxane treatment in breast cancer and steer endeavors toward further enhancing patient care and outcomes.

Novel Strategies Using Sagacious Targeting for Site-Specific Drug Delivery in Breast Cancer Treatment: Clinical Potential and Applications

For more than a decade, researchers have been working to achieve new strategies and smart targeting drug delivery techniques and technologies to treat breast cancer (BC). Nanotechnology presents a hopeful strategy for targeted drug delivery into the building of new therapeutics using the properties of nanomaterials. Nanoparticles are of high regard in the field of diagnosis and the treatment of cancer. The use of these nanoparticles as an encouraging approach in the treatment of various cancers has drawn the interest of researchers in recent years. In order to achieve the maximum therapeutic effectiveness in the treatment of BC, combination therapy has also been adopted, leading to minimal side effects and thus an enhancement in the quality of life for patients. This review article compares, discusses and criticizes the approaches to treat BC using novel design strategies and smart targeting of site-specific drug delivery systems.

Impact of sequence order of anthracyclines and taxanes in neoadjuvant chemotherapy on pathologic complete response rate in HER2-negative breast cancer patients

PURPOSE

Data exploring optimal sequencing of anthracyclines and taxanes as neoadjuvant chemotherapy (NACT) for breast cancer are limited and inconsistent. The objective of this study was to assess the real-world impact of sequence order on pathologic complete response (pCR) and clinical outcomes from NACT.

METHODS

Patients with HER2-negative breast cancer treated with NACT from May 2012 to April 2020 were identified from a prospectively collected institutional database. The primary endpoint was to compare rates of pCR (ypT0/isN0) between patients who received anthracyclines followed by taxanes (AC-T) to those who received taxanes followed by anthracyclines (T-AC). Additional endpoints of interest included clinical complete response, downstaging, Neo-Bioscore, conversion to breast-conserving surgery eligibility, relapse-free survival, and overall survival between groups.

RESULTS

Of the 283 patients who met eligibility criteria, 187 (66%) received AC-T and 96 (34%) received T-AC. Sequence order did not influence the primary endpoint of pCR rate (19% for AC-T vs. 21% for T-AC, p = 0.752). There were also no significant differences in secondary NACT efficacy outcomes between groups. In the overall cohort, pCR rate was higher in patients with triple-negative breast cancer (TNBC) (32% vs. 13% in hormone-positive cancer, p < 0.001) and grade 3 tumors (31% vs. 12% for grade 1-2 tumors, p < 0.001).

CONCLUSIONS

In this real-world analysis of HER2-negative breast cancer patients, there was no differential impact on pCR rate or clinical outcomes from NACT with sequence order of anthracyclines and taxanes. This supports the current variation in prescribing practice.

Sequencing of anthracyclines and taxanes in neoadjuvant and adjuvant therapy for early breast cancer

BACKGROUND

Anthracyclines and taxanes are chemotherapeutic agents widely used in a sequential regimen in the adjuvant and neoadjuvant treatment of early breast cancer to reduce the risk of cancer recurrence. Standard practice is to administer anthracycline-based chemotherapy followed by a taxane. Anthracyclines tend to be administered first as they were established before taxanes for treatment of early breast cancer.

OBJECTIVES

To assess whether the sequence in which anthracyclines and taxanes are administered affects outcomes for people with early breast cancer receiving adjuvant or neoadjuvant therapy.

SEARCH METHODS

We searched Cochrane Breast Cancer's Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization's International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov on 1 February 2018.

SELECTION CRITERIA

Randomised controlled trials comparing administering a taxane prior to an anthracycline with taxane following anthracycline to people with early breast cancer receiving chemotherapy. The studies needed to have reported on at least one of our outcomes of interest, which included overall survival, disease-free survival, pathological response, treatment adherence, toxicity and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data, assessed risk of bias and quality of the evidence. The primary outcome measure was overall survival. Secondary outcomes included disease-free survival, pathological response (in the neoadjuvant setting only), adverse events, treatment adherence and quality of life. For time-to-event outcomes of overall survival and disease-free survival, we derived hazard ratios (HRs) with 95% confidence intervals (CI) where possible. For dichotomous outcomes of pathological complete response, treatment adherence and adverse events, we reported the treatment effect as a risk ratio (RR) with 95% CI where possible. We used GRADE to assess the certainty of the evidence separately for the neoadjuvant and adjuvant settings.

MAIN RESULTS

There were 1415 participants in five neoadjuvant studies and 280 participants in four adjuvant studies involving five treatment comparisons. Four of the five neoadjuvant studies collected data for the primary outcome (overall survival) and two studies had data available; one of the four adjuvant studies collected overall survival data.The neoadjuvant studies suggested that the administration of taxanes first probably resulted in little to no difference in overall survival (HR 0.80, 95% CI 0.60 to 1.08; 947 participants; 2 studies; moderate-certainty evidence) and disease-free survival (HR 0.84, 95% CI 0.65 to 1.09; 828 participants; 1 study; moderate-certainty evidence). Administration of taxanes first also resulted in little to no difference in pathological complete response (absence of cancer in the breast and axilla: RR 1.15, 95% CI 0.96 to 1.38; 1280 participants; 4 studies; high-certainty evidence). However, there appeared to be a trend in favour of taxanes first. Studies reported treatment adherence using a range of measures. Administration of taxanes first probably did not increase the likelihood of requiring dose reductions compared to administration of anthracyclines first (RR 0.81, 95% CI 0.59 to 1.11; 280 participants; 1 study; moderate-certainty evidence). There was probably little to no difference in the risk of grade 3/4 neutropenia (RR 1.25, 95% CI 0.86 to 1.82; 280 participants, 1 study; moderate-certainty evidence) or grade 3/4 neurotoxicity (RR 0.95, 95% CI 0.55 to 1.65; 1108 participants; 2 studies; low-certainty evidence) when taxanes were given first. There were no data on quality of life.Only one adjuvant study collected data on overall survival and disease-free survival but did not report data. Administration of taxanes first reduced the risk of grade 3/4 neutropenia (RR 0.62, 95% CI 0.40 to 0.97; 279 participants; 4 studies, 5 treatment comparisons; high-certainty evidence) and appeared to result in little to no difference in grade 3/4 neurotoxicity (RR 0.78, 95% CI 0.25 to 2.46; 162 participants; 3 studies; low-certainty evidence). There was probably little to no difference in the proportions experiencing dose delays when taxanes are given first compared to anthracyclines given first (RR 0.76, 95% CI 0.52 to 1.12; 238 participants; 3 studies, 4 treatment comparisons; moderate-certainty evidence). One study reported on quality of life and indicated that scores (using the Functional Assessment of Cancer Therapy - Breast Cancer (FACT-B) validated questionnaire) were similar in both groups though did not provide numerical data.

AUTHORS' CONCLUSIONS

In the neoadjuvant setting, there is high- to low-certainty evidence of equivalent outcomes for the sequence in which taxanes are delivered. In the adjuvant setting, none of the studies reported on overall survival or disease-free survival. In most institutions, standard practice would be to deliver anthracycline followed by taxane, and currently available data do not support a change in this practice. We wait for the full-text publication of a relevant neoadjuvant study for women with HER2-negative breast cancer for inclusion in an update of this review.