Role of neoadjuvant chemotherapy in breast cancer patients: Systematic review and meta-analysis

Changes in breast cancer treatment during the COVID-19 pandemic: a Dutch population-based study

PURPOSE

We aimed to compare (1) treatments and time intervals between treatments of breast cancer patients diagnosed during and before the COVID-19 pandemic, and (2) the number of treatments started during and before the pandemic.

METHODS

Women were selected from the Netherlands Cancer Registry. For aim one, odds ratios (OR) and 95% confidence intervals (95%CI) were calculated to compare the treatment of women diagnosed within four periods of 2020: pre-COVID (weeks 1-8), transition (weeks 9-12), lockdown (weeks 13-17), and care restart (weeks 18-26), with data from 2018/2019 as reference. Wilcoxon rank-sums test was used to compare treatment intervals, using a two-sided p-value < 0.05. For aim two, number of treatments started per week in 2020 was compared with 2018/2019.

RESULTS

We selected 34,097 women for aim one. Compared to 2018/2019, neo-adjuvant chemotherapy was less likely for stage I (OR 0.24, 95%CI 0.11-0.53), stage II (OR 0.63, 95%CI 0.47-0.86), and hormone receptor+/HER2- tumors (OR 0.55, 95%CI 0.41-0.75) diagnosed during transition. Time between diagnosis and first treatment decreased for patients diagnosed during lockdown with a stage I (p < 0.01), II (p < 0.01) or III tumor (p = 0.01). We selected 30,002 women for aim two. The number of neo-adjuvant endocrine therapies and surgeries starting in week 14, 2020, increased by 339% and 18%, respectively. The number of adjuvant chemotherapies decreased by 42% in week 15 and increased by 44% in week 22.

CONCLUSION

The pandemic and subsequently altered treatment recommendations affected multiple aspects of the breast cancer treatment strategy and the number of treatments started per week.

Impact of neoadjuvant chemotherapy on surgical complications in breast cancer: A systematic review and meta-analysis

BACKGROUND

The increased use of neoadjuvant chemotherapy (NACT) facilitates an increase in breast-conserving surgery and immediate breast reconstruction. While NACT is considered to have the same oncological safety as adjuvant chemotherapy, evidence on the impact of NACT on surgical outcomes following breast surgery is unclear and varies across studies. The aim of this systematic review and meta-analysis was to assess the impact of NACT on surgical complications in breast cancer patients undergoing any kind of breast surgery.

METHODS

Database searches were conducted (March 26, 2021) to identify studies assessing the impact of NACT on postoperative complications. Studies were included if they compared a group of patients treated with NACT to a control group that was not, and if they reported at least one of our defined outcomes. Primary effect measures were odds ratios (ORs) and mean difference with a 95% confidence interval. Study quality was assessed by the Newcastle-Ottawa Scale.

RESULTS

Twenty-six studies comprising 134,191 patients were included. NACT was not associated with an increased complication rate for overall complications (OR: 1.13, 95% CI: 0.86 to 1.47, p = 0.38), individual postoperative complications, nor surgery duration. There was a non-significant trend towards NACT increasing the risk of seroma, wound complications, skin or nipple necrosis, flap ischemia or loss, and implant loss. A significant difference in blood loss was found, favouring NACT (MD = -75.85, 95% CI: -107.47 to -44.23, p < 0.00001). Heterogeneity was significant between the studies (I²>50%).

CONCLUSION

Compared to a control group, NACT was not found to affect the surgical complications adversely.

Discordance in clinical versus pathological staging in breast cancer: Are we undermining the significance of accurate preoperative staging in the present era?

BACKGROUND

The present era of individualized treatment for breast cancer is influenced by the initial disease status including the anatomical extent, grade, and receptor status. An accurate preoperative staging is the basis of treatment planning and prognostication. Our study aims to determine the discordance between the preoperative clinical and the postoperative pathological stages of breast cancer patients.

METHODOLOGY

The medical records of all non-metastatic breast cancer patients from January 2017 to December 2018 who underwent upfront surgery were reviewed. They were staged as per the eighth AJCC and the concordance between the clinical (c) and pathological T (tumor), N (nodal), and final AJCC stage was studied. A Chi-square test was used to determine factors that significantly correlate with disease discordance.

RESULTS

A total of 307 breast cancer patients were analyzed. Among these, 43.3% were hormone receptor-positive, 30.6% were Her2 positive and 26% were triple-negative. Overall stage discordance was seen in 48.5% (n = 149) patients (upstaging in 22.1%, downstaging in 26.4%). The discordance rate was 48.9% for T stage (cT versus pT) and 57.4% for N stage (cN versus pN). Among patients with clinically node-negative disease, 53.4% were found to have positive nodes on histopathology, while 27.2% had vice versa. Overall, the factors associated with upstaging were ER-positive, Her2 positive and triple-negative status (all p < 0.05), while none of the factors showed significant association with downstaging.

CONCLUSIONS

About half of breast cancer patients had discordance between clinical and pathological staging with higher discordance in the nodal stage. This changes the disease prognosis, and may also affect the offered surgical treatment and radiotherapy. Thus highlighting the need for a precise pre-operative staging. Also, this information will aid clinicians in discussions with patients, keeping in mind the likelihood of change in disease staging and management.

Oncologic Outcomes of Sentinel Lymph Node Surgery After Neoadjuvant Chemotherapy for Node-Positive Breast Cancer

BACKGROUND

Sentinel lymph node (SLN) surgery after neoadjuvant chemotherapy (NAC) has been well studied. However, outcomes data addressing the oncologic safety of this technique are sparse. This study aimed to evaluate use of SLN surgery versus axillary lymph node dissection (ALND) for clinically node-positive patients treated with NAC and to report outcomes.

METHODS

The study identified patients at the authors' institution with biopsy proven clinically node-positive (cN1-cN3) breast cancer undergoing axillary surgery after NAC from 2009 to 2019. Practice patterns and outcomes were evaluated.

RESULTS

Of 602 patients, 52.3% underwent SLN surgery. Use of SLN surgery increased significantly over time, reaching 75.3% during 2015-2019. For 52.5% of the patients who had an SLN identified, ALND was not used. Use of ALND (± SLN surgery) decreased from 100% in 2009 to 57.2% in 2015-2019. The nodal positivity rate of patients who proceeded directly to ALND was 64.5% (185/287), increasing significantly over time. Factors significantly associated with performing SLN surgery on multivariable analysis were lower presenting clinical T category, lower presenting clinical N category (cN1 vs cN2-3) and HER2-positive status. During the median 34-month follow-up period, 17 regional recurrences were observed (16/443 with ALND; 1/159 with SLN surgery alone), for a 2-year freedom-from-regional-recurrence rate of 99.1% among the SLN surgery patients and 96.4% among the ALND patients (p = 0.10).

CONCLUSIONS

For cN1-3 breast cancer treated with NAC, SLN surgery has been incorporated into clinical practice at the authors' institution. In this study, selection for SLN surgery was based on clinical factors and tumor biology. More than half of the patients who were selected for SLN surgery were spared ALND, with a low nodal failure rate and no recurrence-free survival disadvantage at 2 years.

Effectiveness of Added Targeted Therapies to Neoadjuvant Chemotherapy for Breast Cancer: A Systematic Review and Meta-analysis

Over the past several years, targeted therapy has been increasingly used in the management of breast cancer. Reported results for targeted therapies are variable, as some randomized controlled trials (RCTs) reported a strong effect, whereas others reported no or minimal effect on the outcomes. Accordingly, the present study aimed to assess the effect of the addition of targeted therapies to neoadjuvant chemotherapy on tumor response rates, breast conserving surgeries, and survival outcomes. PubMed and the Cochrane register of clinical trials were searched on April 28, 2017 for RCTs comparing addition of targeted therapies to neoadjuvant chemotherapy. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the screening of records and data extraction were performed by 2 independent reviewers. Publication bias and risk of bias were assessed by the Egger test and the Cochrane tool for risk of bias assessment, respectively. The fixed effect method or random effect method were used to synthesize the results depending on the heterogeneity assessed by the I2 statistic. A total of 17 RCTs including trastuzumab (n = 5), bevacizumab (n = 7), and other targeted therapies (n = 5) were found eligible. Pathologic complete response was significantly higher with trastuzumab (relative risk [RR], 2.20; 95% confidence interval [CI], 1.62-2.99) and bevacizumab (RR, 1.23; 95% CI, 1.11-1.37), but not with other targeted therapies. Bevacizumab for human epidermal growth factor receptor 2 (HER2)-negative breast cancer was found to be associated with improved overall (hazard ratio, 0.69; 95% CI, 0.53-0.90) and disease-free survival (hazard ratio, 0.83; 95% CI, 0.67-1.03). The addition of targeted therapies may not significantly increase breast conserving surgery rates (RR, 1.04; 95% CI, 0.97-1.12). The addition of targeted therapies, especially trastuzumab for patients with HER2-positive breast cancer and bevacizumab for patients with HER2-negative breast cancer significantly increased pathologic complete response, overall response, and clinical complete response but not breast conserving surgery rates.

Effectiveness of taxanes over anthracyclines in neoadjuvant setting: A systematic-review and meta-analysis

BACKGROUND

Anthracyclines and taxanes are more active group of chemotherapy regimen. Randomized controlled trials (RCTs) reported variable evidences regarding efficacy of taxanes over anthracyclines for tumor response and survival outcomes. The present study compares the relative efficacy of taxanes over anthracyclines using pathological complete response (pCR), clinical responses, breast-conserving surgeries and survival outcomes in female breast cancer patients by systematic review and meta-analysis of available RCTs.

AIM

To assess the effectiveness of taxanes over anthracyclines in neoadjuvant setting in terms of tumor response and survival outcomes.

METHODS

All RCTs assessing efficacy of taxanes over anthracyclines in neoadjuvant setting for management of breast cancer searched through PubMed and Cochrane register of controlled trials on 28 April 2017 and published in English language were considered. Following PRISMA guideline, retrieved records were screened and data were extracted by two independent reviewers. Meta-analysis was performed using fixed effect or random effect method depending on heterogeneity assessed using I² statistic. Subgroup meta-analyses on the basis of taxane alone or taxane along with anthracycline in comparison to anthracycline alone were also performed for each considered outcomes.

RESULTS

A total of 16 RCTs involving 6752 breast cancer patients were found eligible. Taxanes based chemotherapy significantly improved pCR (n = 7, RR = 1.48, 95%CI: 1.04-2.12), disease free survival [n = 6, RR = 0.89 (0.80-0.99)] and loco-regional recurrence free survival [n = 4, RR = 0.74 (0.59-0.94)]. Interestingly in subgroup analysis, addition of taxane to anthracyclines showed better effectiveness regarding these survivals over anthracyclines than taxane alone over anthracycline.

CONCLUSION

Addition of taxanes to anthracyclines based chemotherapy significantly improves pCR, disease free survival and loco-regional recurrence free survival but with no significant impact on breast conservation rates.