Practical consensus recommendations regarding the management of HER2 neu positive early breast cancer

Clinicopathological response to neoadjuvant therapies and pathological complete response as a biomarker of survival in human epidermal growth factor receptor-2 enriched breast cancer - A retrospective cohort study

BACKGROUND

Human epidermal growth factor receptor-2 (HER2) is overexpressed in 20-25% of breast cancers. Complete eradication of disease following neoadjuvant therapies and chemotherapy has been referred to as pathological complete response (pCR).

AIMS

To determine clinicopathological predictors of pCR to neoadjuvant therapies and to evaluate pCR as a surrogate to enhanced survival.

METHODS

Consecutive female patients with HER2 positive (HER+) breast cancer managed surgically in a single institution between 2005 and 2015 were included. Descriptive statistics and binary logistic regression were used to determine predictors of pCR. Appraisal of pCR as a predictor of survival was performed using Kaplan-Meier curves and Cox regression analysis.

RESULTS

451 patients were included with a mean age of 56.6 ± 13.4 years (range 23-95). Disease-free (DFS) and overall survival (OS) was 82.3% (371/451) and 82.6% (376/451) respectively with a median follow-up of 108.0 months (range 3-184.0). 118 were treated in the neoadjuvant setting (26.2%): tumour size <50 mm (Odds Ratio (OR): 12.156, P = 0.023) and progesterone receptor negativity (OR: 2.762, P = 0.008) independently predicted breast pCR, while ductal carcinoma (OR: 3.203, P = 0.030) and grade 3 disease (OR: 2.788, P = 0.018) predicted axillary pCR. Both breast and axillary pCR predicted enhanced DFS (Hazard Ratio (HR): 0.470 & HR: 0.449) and OS (HR: 0.383 & HR: 0.307). Axillary pCR independently predicted improved OS (HR: 0.326).

CONCLUSION

pCR is sensitive biomarker and surrogate to survival outcomes in HER2+ breast cancer. Patients likely to achieve pCR may be predicted from traditional clinicopathological characteristics and molecular parameters.

A quality evaluation of the clinical practice guidelines on breast cancer using the RIGHT checklist

Background

Breast cancer is the most frequent type of cancer in women. The methodological quality of clinical practice guidelines (CPGs) on breast cancer has been shown to be heterogeneous. The aim of our study was to evaluate the quality of breast cancer CPGs published in years 2018-2020, using the Reporting Items for Practice Guidelines in Healthcare (RIGHT) checklist.

Methods

We searched Medline (via PubMed), Chinese National Knowledge Infrastructure (CNKI), Wanfang and Chinese Biomedical Literature (CBM) as well as websites of guideline organizations for CPGs on breast cancer published between 2018 and 2020. We used the RIGHT checklist to evaluate the reporting quality of the included guidelines by assessing whether the CPGs adhered to each item of the checklist and calculated the proportions of appropriately reported RIGHT checklist items. We also presented the adherence reporting rates for each guideline and the mean rates for each of the seven domains of the RIGHT checklist.

Results

A total of 45 guidelines were included. Eighteen (40.0%) guidelines had an overall reporting rate below 50% and only three (6.7%) reported more than 80% of the items. The domains “Basic information” and “Background” had the highest reporting rates (75.9% and 62.5%, respectively). The mean reporting rates of the domains “Evidence”, “Recommendation”, “Review and quality assurance”, “Funding and declaration and management of interests” and “Other information” were 42.7%, 53.0%, 33.3%, 45.0%, and 44.4%, respectively.

Conclusions

The reporting quality varied among guidelines for breast cancer, showing the need for improvement in reporting the contents. Guideline developers should pay more attention to reporting the evidence, review and quality assurance, and funding and declaration and management of interests in future.

Neoadjuvant chemotherapy with biosimilar trastuzumab in human epidermal growth factor receptor 2 overexpressed non-metastatic breast cancer: patterns of use and clinical outcomes in India

BACKGROUND

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer is associated with poor prognosis and access to anti-HER2 treatment is still a challenge in lower-middle income countries. The availability of the biosimilar trastuzumab has improved access by lowering the costs. We report the pattern of use of neoadjuvant ± adjuvant trastuzumab and outcomes in patients with HER2-positive non-metastatic breast cancer treated with regimens incorporating shorter durations of therapy and the use of the biosimilar trastuzumab compared to the innovator.

METHODS

We conducted a retrospective analysis of patients with non-metastatic HER2-positive breast cancer treated with neoadjuvant ± adjuvant trastuzumab (innovator (n = 34 (33%)) and biosimilar (n = 70 (67%)) manufactured by Biocon Biologics) with chemotherapy. Information regarding chemotherapy regimens, duration of trastuzumab use (≤12 weeks and >12 weeks), pathological response (Miller Payne grade), disease free survival (DFS), overall survival (OS) and safety data were collected from electronic medical records.

RESULTS

A total of 135 patients were analysed with a median age of 51 years (range: 23-82); of these, 57% were postmenopausal, 31.8% were hormone receptor positive and 62.9% had stage III disease. The overall pathological complete response (p-CR) in both breast and axilla increased to 37.6% in patients treated with trastuzumab preoperatively as compared to 22.2% in patients who did not receive any trastuzumab. Patients receiving innovator trastuzumab and biosimilar trastuzumab showed a p-CR of 28.5% and 41.7%, respectively. At a median follow-up of 42 months (range: 3-114), there were 18 relapses and 11 deaths. The 3-year DFS was 87.1% and OS was 92.2%. Cardiac dysfunction developed in 4 of 78 (5.1%) evaluable patients.

CONCLUSION

Access to anti-HER2 therapy in the treatment of non-metastatic HER2-positive breast cancer in resource-constrained settings has improved significantly with the availability of the biosimilar trastuzumab. Imbalances in patient profiles at baseline in routine clinical practice led to inconclusive outcomes of ≤12 weeks versus >12 weeks trastuzumab treatment. However, on the basis of historical data, patients could be offered shorter duration of trastuzumab when a standard 1-year treatment of adjuvant trastuzumab is not feasible in resource-constrained settings. The p-CR using the biosimilar trastuzumab in neoadjuvant treatment has been observed to be comparable to the innovator trastuzumab.