Factors Affecting Pathological Complete Response in Locally Advanced Breast Cancer Cases Receiving Neoadjuvant Therapy: A Comprehensive Literature Review

Predictors of High-Burden Residual Axillary Disease After Neoadjuvant Therapy in Breast Cancer

BACKGROUND

Neoadjuvant therapy (NAT) plays a crucial role in breast cancer (BC) management by enabling tumor and nodal downstaging. While axillary lymph node dissection (ALND) remains the standard for patients with residual nodal disease after NAT, its prognostic benefit is debated. Identifying predictors of high-burden residual axillary disease may guide treatment intensification and surgical de-escalation strategies.

METHODS

We retrospectively analyzed 262 BC patients treated with NAT followed by ALND between 2006 and 2023. Patients were stratified into low- (ypN0-mi-1) and high-burden (ypN2-3) residual axillary disease groups. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of high-burden residual disease.

RESULTS

High-burden residual axillary disease was observed in 35.9% of patients. Baseline cN+ status (OR = 7.697, p = 0.013), HR+/HER2- subtype (OR = 3.945, p = 0.003), and larger post-NAT tumor size (OR = 1.043, p < 0.001) were independent predictors.

CONCLUSIONS

Identifying patients at risk of high-burden residual axillary disease is essential to optimize neoadjuvant strategies. Increasing axillary pathological complete response may reduce the need for ALND, minimizing surgical morbidity without compromising oncological outcomes.

Dismal pathological response to neoadjuvant chemotherapy in stage III breast cancer patients in Tanzania: A retrospective review

Response to neoadjuvant treatment in breast cancer has been associated with good oncological outcomes. In Tanzania, a majority of breast cancer patients are diagnosed at stage III; hence, they almost always require neoadjuvant therapy. However, the response to neoadjuvant therapy in these patients remains unknown. This study examined the pathological responses in women with stage III breast cancer who underwent neoadjuvant therapy and identified sociodemographic and clinical predictors of the pathological response in this cohort. This hospital-based retrospective cohort study was conducted between December 2021 and April 2022. It included women with breast cancer who received neoadjuvant therapy and underwent surgery for breast cancer at Muhimbili National Hospital in Tanzania, from January 2018 through December 2021. Data analysis was performed using SPSS version 25. A complete pathological response was identified upon pathological review of the mastectomy specimen. Chi-square tests and Fischer's exact tests were used to evaluate the factors associated with a complete pathological response, with a p value of less than 0.05 indicating statistical significance. Ethical approval was obtained from the Muhimbili University of Health and Allied Sciences Institutional Review Board. The study complied with the Helsinki Declaration on studies involving human subjects. A total of 181 breast cancer patients were recruited for the study, with a mean age of 51±12.6 (28-89) years. A complete pathological response to neoadjuvant therapy was observed in 40 (22.1%) patients which is relatively lower compared to studies from Western countries. Disease stage at diagnosis was associated with response to neoadjuvant therapy, with those at stage IIIA showing better complete response than those at stages IIIB and IIIC indicating a need to improve diagnostic strategies to capture patients in the earlier stages to improve outcomes.

Retrospective Study to Determine Factors Influencing Outcome in Patients With Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer Receiving Neoadjuvant Chemotherapy

PURPOSE

There are scant data on patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer treated with neoadjuvant therapy (NAT) in real-world settings with limited access to HER2-targeted therapy.

METHODS

This was a retrospective analysis of patients with nonmetastatic, HER2-positive breast cancer treated with NAT between January 2014 and December 2018 to determine factors affecting pathologic complete response (pCR), event-free survival (EFS), and overall survival (OS).

RESULTS

The cohort comprised 1,004 patients with a median age of 47 years, 533 (53.1%) with clinical T3/T4 tumors, 466 (46.4%) with clinical N2/3 status, and 527 (52.5%) with hormone receptor-positive disease. Trastuzumab was given to 528 (52.6%) patients in the neoadjuvant setting and 711 (70.8%) patients in neoadjuvant and/or postoperative settings. pCR was achieved in 226 (22.5%) patients; the 5-year EFS in the whole cohort, pCR group, and no-pCR group was 63.5% (95% CI, 60.36 to 66.63), 86.1% (95% CI, 81.59 to 90.60), and 57% ([95% CI, 53.47 to 60.52]; P < .001), respectively. In multivariable analysis in the full cohort, smaller tumor size (cT1/T2 v cT3/T4), higher grade (III v II), hormone receptor-negative status, and use of neoadjuvant HER2-targeted therapy were significantly associated with higher pCR, and smaller tumor size (cT1/T2 v cT3/T4), lower node involvement (cN0/N1 v cN2/N3), achievement of pCR, and receiving trastuzumab were significantly associated with higher EFS and OS.

CONCLUSION

In a setting with constrained access to HER2-targeted therapy, lower clinical tumor burden and receiving trastuzumab were significantly associated with increased pCR and survival in patients with HER2-positive breast cancer treated with NAT. Efforts should be made to enhance early diagnosis and access to HER2-targeted therapy worldwide.

Vitamin D Supplementation Improves Pathological Complete Response in Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy: A Randomized Clinical Trial

This study aimed to evaluate the effect of vitamin D (VD) supplementation on the pathological complete response (pCR) rate in women with breast cancer (BC) undergoing neoadjuvant chemotherapy (NCT). A randomized clinical trial was conducted with 80 women aged ≥45years with BC who were eligible for NCT. Women were randomized into two groups: VD group, daily supplementation with 2,000IU of cholecalciferol (n = 40) or placebo (n = 40), for 6 months. The primary outcome measure was the pCR rate. Serum 25-hydroxyvitamin-D [25(OH)D] levels were measured after BC diagnosis and the end of NCT. Of the 80 randomized women, 75 completed the NCT and underwent surgery. Baseline 25(OH)D values indicated hypovitaminosis D in both groups (VD: 19.6 ± 5.8 ng/mL and placebo: 21 ± 7.9 ng/mL, p = 0.33). After 6 months, 25(OH)D levels increased in the VD group compared to the placebo group (28 ± 8.7 vs. 20.2 ± 6.1 ng/mL, p = 0.03). The pCR rate was higher in women supplemented with VD when compared than the placebo (43% vs. 24%, p = 0.04). Adjusted logistic regression showed that women with 25(OH)D levels ≥20ng/mL were more likely to achieve pCR (OR3.65, 95%CI 1.09-12.8, p = 0.04). Women with BC undergoing NCT who received supplementation with 2,000IU of VD were more likely to achieve a pathological complete response than women in the placebo group.

TRIAL REGISTRATION

Ensaiosclinicos.gov.br, identifier RBR-10k4gqdg.

Predictive factors for complete pathologic response in luminal breast cancer: impact of ki67 and HER2 low expression

Background

Complete pathological response to neoadjuvant treatment (NAT) in breast cancer is associated with prolonged survival. Compared to other breast cancer immunophenotypes, luminal tumors are the least chemosensitive with low rates of pathological response within this molecular subtype. Thus, finding predictors of response in this subset remains challenging. The emerging concept of low human epidermal growth factor receptor 2 (HER2) expression has led to a repurpose of the current prognostic system. Little is known about its correlation with response to NAT.

Objectives

This study aims to evaluate predictors of response in early-stage luminal breast cancer receiving neoadjuvant chemotherapy.

Design

A total of 252 luminal patients who received NAT were retrospectively assessed in this cohort study.

Methods

We analyzed the correlation of ki67 and HER2 low expression with the rate of pathologic response. Using ki67 as a continuous variable and applying the receiver operating characteristic curves method.

Results

We identified that in patients with a ki67 expression level >37%, the probability of having a complete pathological response was 4.80 times higher (odds ratio = 4.80, 95% confidence interval: 1.92-12.04). In Her2-low breast cancer patients, Her2 expression did not correlate with a better response rate.

Conclusion

In our study, a ki67 expression value greater than 37% constitutes a predictive biomarker of pathological complete response in the subgroup of patients with luminal B tumors and could be considered, therefore, an indicator for treatment decisions in this subgroup.

Comprehensive Axillary Management of Clinically Node-Positive (cN+) Breast Cancer Patients: A Narrative Review on Neoadjuvant Chemotherapy

BACKGROUND

In breast cancer (BC) patients, axillary management has undergone major improvements over the last few years, and efforts to identify the optimal strategy for the management of axillary surgery are still ongoing.

METHODS

In current clinical practice, women with clinically node-positive (cN+) BC usually receive neoadjuvant chemotherapy (NACT) with the aim of reducing the extent of primary disease and, thus, allowing for axillary-conservative surgery. Remarkably, after NACT, up to one out of three patients achieves an axillary pathologic complete response, which, in turn, is associated with a more favorable prognosis than residual axillary disease. However, NACT is not without drawbacks, as NACT-associated inflammation can damage lymphatic vessels. Furthermore, varying degrees of response may occur in the axillary lymph nodes, increasing the false negative rate for sentinel biopsy.

RESULTS

At present, there is no consensus on the optimal approach in patients with cN+ BC undergoing NACT, although multidisciplinary management seems to be recommended.

CONCLUSIONS

This narrative review provides a comprehensive overview of axillary management in cN+ BC patients undergoing NACT. It uses a multidisciplinary approach that encompasses the oncological management perspectives, as well as surgical and chemotherapeutic viewpoints.

Prognostic Evaluation of Piezo2 Channels in Mammary Gland Carcinoma

In the last decade, a group of Ca2+ channels called Piezo were discovered, demonstrating a decisive role in the cellular response to mechanical stimuli and being essential in the biological behavior of cells regarding the extracellular compartment. Several investigations have suggested a potential role in carcinogenesis, with a tumor suppressor role in some cases but increased expression in several high-grade neoplasms. Regarding Piezo2 expression in mammary gland neoplasms, a protective role for Piezo2 was initially suggested, but a subsequent study demonstrated a relationship between Piezo2 expression and the highly aggressive triple-negative phenotype of breast carcinoma. A cohort of 125 patients with clinical follow-up was chosen to study Piezo2 expression and clarify its clinical implications using the same immunohistochemical evaluation performed for other breast carcinoma parameters. Fisher's exact test was chosen to identify potential relationships between the different variables. A significant association was found with the Ki67 proliferation index, but not with mitoses. The tendency of most proliferative tumors was to have an increased score for Piezo2. A similar association was found between Piezo2 expression and perineural invasion.