Neoadjuvant therapy in early-stage breast cancer

Comparing survival outcomes between neoadjuvant and adjuvant chemotherapy within T2N1M0 stage hormone receptor-positive, HER2-negative breast cancer: a retrospective cohort study based on SEER database

BACKGROUND

Guideline recommendations for the application of neoadjuvant chemotherapy (NACT) in T2N1M0 stage hormone receptor-positive, HER2-negative (HR + /HER2-) breast cancer are ambiguous. The debate continues regarding whether NACT or adjuvant chemotherapy (ACT) offers superior survival outcomes for these patients.

MATERIALS AND METHODS

Female patients diagnosed with HR + /HER2- breast cancer at T2N1M0 stage between 2010 and 2020, were identified from the Surveillance, Epidemiology, and End Results database and divided into two groups, the NACT group and the ACT group. Propensity score matching (PSM) was utilized to establish balanced cohorts between groups, considering baseline features. Kaplan-Meier (K-M) analysis and the Cox proportional hazards model were executed to assess the efficacy of both NACT and ACT in terms of overall survival (OS) and breast cancer-specific survival (BCSS). A logistic regression model was employed to examine the association between predictive variables and response to NACT.

RESULTS

After PSM, 4,682 patients were finally included. K-M curves showed that patients receiving NACT exhibited significantly worse OS and BCSS when compared with patients undergoing ACT. Multivariable Cox analysis indicated that not achieving pathologic complete response (non-pCR) after NACT (versus ACT), was identified as an adverse prognostic factor for OS (HR 1.58, 95% CI 1.36-1.83) and BCSS (HR 1.70, 95% CI 1.44-2. 02). The logistic regression model revealed that low tumor grade independently predicted non-pCR.

CONCLUSION

Among T2N1M0 stage HR + /HER2- patients, OS and BCSS of NACT were inferior to ACT. Patients who attained non-pCR after NACT demonstrated significantly worse survival outcomes compared with those who received ACT.

Metadherin inhibits chemosensitivity of triple-negative breast cancer to paclitaxel via activation of AKT/GSK-3β signaling pathway

Triple-negative breast cancer (TNBC) has an aggressive clinical course, and paclitaxel (PTX)-based chemotherapy remains the main therapeutic drug. Metadherin (MTDH) acts as an oncogene that regulates proliferation, invasion, metastasis, and chemoresistance. This study aimed to investigate whether TNBC chemosensitivity to PTX was related to the MTDH/AKT/glycogen synthase kinase-3beta (GSK-3β) pathway. Clinical baseline characteristics and immunohistochemistry (IHC) were used to evaluate the expression and prognosis of MTDH and AKT (protein kinase B, PKB) in TNBC patient samples. MTDH shRNA, MTDH overexpression vector, MK-2206, and PTX intervention were used in cell models and mouse tumor-bearing models. Afterwards, mRNA and protein levels were assessed using quantitative real-time polymerase chain reaction and Western blot. Evaluate the level of tumor cell apoptosis and cell cycle using flow cytometry. Cell viability was detected using Cell Count Kit 8. The in vivo imaging system is used to analyze the growth of tumors. We found that higher expression of MTDH or AKT resulted in poorer disease-free survival and a lower Miller-Payne grade. MTDH promotes cell proliferation and increases p-AKT and p-GSK-3β expression in TNBC cells. Notably, suppression of AKT terminated MTDH overexpression-induced cell proliferation and apoptosis. MTDH knockdown or the AKT inhibitor MK2206 reduced the p-AKT and p-GSK-3β ratio, reduced cell viability and proliferation, increased cell apoptosis, and increased chemosensitivity to PTX. In vivo, xenograft tumors of an MTDH knockdown+MK2206 group treated with PTX were the smallest compared to other groups. In short, MTDH inhibits TNBC chemosensitivity to PTX by activating the AKT/GSK-3β signaling pathway.

Real‑world data indicated that neoadjuvant chemotherapy alone was associated with a higher risk of tumor recurrence in high‑risk breast cancer subgroup patients

Numerous clinical trials have reported equal effects of tumor control between neoadjuvant chemotherapy (NAC) and adjuvant chemotherapy (AC) in patients with breast cancer (BC). However, this conclusion has not been verified in practice. The present retrospective study evaluated if there were different risk profiles for NAC, AC and their combinative modes on disease-free survival (DFS) in patients with BC using real-world data. All women with primary unilateral Stage I-III BC and first recurrence in 2008-2018 at The Fourth Hospital of Hebei Medical University were retrospectively identified for enrollment. The four modes of chemotherapy administered for primary BC were classified as 'None', 'NAC only', 'NAC+AC' and 'AC only'. One multivariate Cox model was used to estimate the adjusted Hazard Ratio (HR) and P-value. Covariates included age, Easter Cooperative Oncology Group grade, T stage, N stage, pathology, grade, lymphovascular invasion (LVI), BC subtype, number of chemotherapy cycles and other therapies. Amongst 637 patients, who had a mean age of 48.2 years at BC diagnosis and 50.9 years at recurrence, the median DFS by the 'None' (n=27), 'NAC only' (n=47), 'NAC+AC' (n=118) and 'AC only' (n=445) modes were 31.4, 16.6, 22.6 and 28.4 months (P<0.001), respectively. Compared with the 'AC only', adjusted HR (P-value) of the 'None', 'NAC only' and 'NAC+AC' modes on tumor recurrence were 1.182 (0.551), 1.481 (0.037) and 1.102 (0.523), respectively. The adjusted HR of 'NAC only' vs. 'AC only' modes were 1.448 (P=0.157) for locoregional recurrence and 2.675 (P=0.003) for distant recurrence. Stratified analyses further indicated that the 'NAC only' mode was associated with a higher recurrence risk in T3-4, N2-3, LVI-positive, or HER2-negative subgroup patients. In conclusion, NAC alone was associated with a higher risk of tumor recurrence in high-risk BC subgroup patients in real-world data. Patient selection of chemotherapy mode was involved in practice but could not fully explain this finding. The 'inadequate' NAC was highly likely to have accounted for this observation.

Treatment Strategies for Residual Disease following Neoadjuvant Chemotherapy in Patients with Early-Stage Breast Cancer

Breast cancer continues to be the most diagnosed cancer among women worldwide. Neoadjuvant chemotherapy is the standard of care for breast cancer patients with locally advanced disease and patients with poor pathological features, such as triple-negative (TN) or human epidermal growth factor receptor-2 (HER2)-positive subtypes. Neoadjuvant therapy offers several advantages, including better surgical outcomes, early systemic treatment for micro-metastases, and accurate tumor biology and chemosensitivity assessment. Multiple studies have shown that achieving pathological complete response (pCR) following neoadjuvant chemotherapy is associated with better prognosis and better treatment outcomes; almost half of such patients may fail to achieve pCR. Tumor proliferative index, hormone receptor (HR) status, and HER2 expression are the major predictors of pCR. Strategies to improve pCR have been dependent on augmenting neoadjuvant chemotherapy with the addition of taxanes and dual anti-HER2 targeted therapy in patients with HER2-positive tumor, and more recently, immunotherapy for patients with TN disease. The clinical management of patients with residual disease following neoadjuvant chemotherapy varies and depends mostly on the level of HR expression and HER2 status. Recent data have suggested that switching trastuzumab to trastuzumab-emtansine (T-DM1) in patients with HER2-positive disease and the addition of capecitabine for patients with HER2-negative and HR-negative subtype is associated with a better outcome; both strategies are incorporated into current clinical practice guidelines. This paper reviews available and ongoing studies addressing strategies to better manage patients who continue to have residual disease following neoadjuvant chemotherapy.

Systemic treatment of patients with early breast cancer: recent updates and state of the art

This review is focused on trials generating results that potentially impacted clinical practice since the 2017 St. Gallen Consensus; the most impactful trial was KATHERINE, which revealed a 11.3% absolute iDFS improvement with T-DM1 (compared to trastuzumab) in HER2-positive breast cancer patients who presented invasive residual disease following neoadjuvant treatment. These results, if reinforced by a subsequent overall survival benefit, will consolidate neoadjuvant treatment as the standard-of-care for most HER2-positive breast cancer patients. The addition of pertuzumab to adjuvant trastuzumab (APHINITY) or extending anti-HER2 therapy with 1 year of neratinib (ExteNET) also improved outcomes, but in a more modest way. In triple-negative early breast cancer patients presenting invasive residual disease after neoadjuvant chemotherapy, the CREATE-X trial demonstrated the benefit of post-neoadjuvant capecitabine. In patients with luminal tumours, updated results of the SOFT/TEXT trials confirmed the benefit of aromatase inhibitors plus ovarian suppression in high-risk premenopausal patients, and the 12-year results of the BIG1-98 trial demonstrated a sustained trend in favour of letrozole compared to tamoxifen in the adjuvant treatment of postmenopausal patients. The TAILOR-X study showed that, overall, patients with an intermediate recurrence risk score (11-25) in the OncotypeDX 21-gene assay did not benefit from adjuvant chemotherapy. A meta-analysis performed by the EBCTCG demonstrated that extended adjuvant aromatase inhibitors modestly reduced breast cancer recurrence risks, with a more pronounced benefit in patients previously treated with tamoxifen. Finally, an EBCTCG meta-analysis including patients with all breast cancer subtypes showed that dose-dense chemotherapy improved survival when compared to conventionally-timed chemotherapy.

Post-neoadjuvant treatment and the management of residual disease in breast cancer: state of the art and perspectives

Achieving a pathologic complete response after neoadjuvant treatment is associated with improved prognosis in breast cancer. The CREATE-X trial demonstrated a significant survival improvement with capecitabine in patients with residual invasive disease after neoadjuvant chemotherapy, and the KATHERINE trial showed a significant benefit of trastuzumab-emtansine (TDM1) in human epidermal growth factor receptor 2 (HER2)-positive patients who did not achieve a pathologic complete response after neoadjuvant treatment, creating interesting alternatives of post-neoadjuvant treatments for high-risk patients. New agents are arising as therapeutic options for metastatic breast cancer such as the cyclin-dependent kinase inhibitors and the immune-checkpoint inhibitors, but none has been incorporated into the post-neoadjuvant setting so far. Evolving techniques such as next-generation sequencing and gene expression profiles have improved our knowledge regarding the biology of residual disease, and also on the mechanisms involved in treatment resistance. The present manuscript reviews the current available strategies, the ongoing trials, the potential biomarker-guided approaches and the perspectives for the post-neoadjuvant treatment and the management of residual disease after neoadjuvant treatment in breast cancer.

Beclin1 inhibition enhances paclitaxel‑mediated cytotoxicity in breast cancer in vitro and in vivo

Beclin1, a key regulator of autophagy, has been demonstrated to be associated with cancer cell resistance to chemotherapy. Paclitaxel is a conventional chemotherapeutic drug used in the clinical treatment of breast cancer. However, the function and mechanism of Beclin1 in paclitaxel‑mediated cytotoxicity in breast cancer are not well defined. The present study demonstrated that paclitaxel suppressed cell viability and Beclin1 expression levels in BT‑474 breast cancer cells in a dose‑ and time‑dependent fashion. Compared with the control, the knockdown of Beclin1 significantly enhanced breast cancer cell death via the induction of caspase‑dependent apoptosis following paclitaxel treatment in vitro (P<0.05). In a BT‑474 xenograft model, paclitaxel achieved substantial inhibition of tumor growth in the Beclin1 knockdown group compared with the control group. Furthermore, analysis of the publicly available Gene Expression Omnibus datasets revealed a clinical correlation between Beclin1 levels and the response to paclitaxel therapy in patients with breast cancer. Collectively, the present results suggest that Beclin1 protects breast cancer cells from apoptotic death. Thus, the inhibition of Beclin1 may be a novel way to improve the effect of paclitaxel. Additionally, Beclin1 may function as a favorable prognostic biomarker for paclitaxel treatment in patients with breast cancer.

Molecular Signaling of Progesterone, Growth Hormone, Wnt, and HER in Mammary Glands of Dogs, Rodents, and Humans: New Treatment Target Identification

Mammary tumors are the most common form of neoplasia in the bitch. Female dogs are protected when they are spayed before the first estrus cycle, but this effect readily disappears and is already absent when dogs are spayed after the second heat. As the ovaries are removed during spaying, ovarian steroids are assumed to play an essential role in tumor development. The sensitivity toward tumor development is already present during early life, which may be caused by early mutations in stem cells during the first estrus cycles. Later on in life, tumors arise that are mostly steroid-receptor positive, although a small subset of tumors overexpressing human epidermal growth factor 2 (HER2) and some lacking estrogen receptor, progesterone receptor (PR), and HER2 (triple negative) are present, as is the situation in humans. Progesterone (P₄), acting through PR, is the major steroid involved in outgrowth of mammary tissue. PRs are expressed in two forms, the progesterone receptor A (PRA) and progesterone receptor B (PRB) isoforms derived from splice variants from a single gene. The dog and the whole family of canids have only a functional PRA isoform, whereas the PRB isoform, if expressed at all, is devoid of intrinsic biological activity. In human breast cancer, overexpression of the PRA isoform is related to more aggressive carcinomas making the dog a unique model to study PRA-related mammary cancer. Administration of P₄ to adult dogs results in local mammary expression of growth hormone (GH) and wing less-type mouse mammary tumor virus integration site family 4 (Wnt4). Both proteins play a role in activation of mammary stem cells. In this review, we summarize what is known on P₄, GH, and Wnt signaling in canine mammary cancer, how the family of HER receptors could interact with this signaling, and what this means for comparative and translational oncological aspects of human breast cancer development.

Pathologic Evaluation of Breast Cancer after Neoadjuvant Therapy

Breast cancer, one of the most common cancers in women, has various treatment modalities. Neoadjuvant therapy (NAT) has been used in many clinical trials because it is easy to evaluate the treatment response to therapeutic agents in a short time period; consequently, NAT is currently a standard treatment modality for large-sized and locally advanced breast cancers, and its use in early-stage breast cancer is becoming more common. Thus, chances to encounter breast tissue from patients treated with NAT is increasing. However, systems for handling and evaluating such specimens have not been established. Several evaluation systems emphasize a multidisciplinary approach to increase the accuracy of breast cancer assessment. Thus, detailed and systematic evaluation of clinical, radiologic, and pathologic findings is important. In this review, we compare the major problems of each evaluation system and discuss important points for handling and evaluating NAT-treated breast specimens.

Effect of Neoadjuvant Chemotherapy on the Surgical Treatment of Patients With Locally Advanced Breast Cancer Requiring Initial Mastectomy

BACKGROUND

The aim of this study was to assess the rate of breast-conserving surgery (BCS) after neoadjuvant chemotherapy (nCT) in patients for whom mastectomy (MT) was, initially, the only conceivable surgical option.

PATIENTS AND METHODS

Between 2007 and 2012, 168 patients from a single center received nCT. Among these patients, we focused on the ones who received nCT (n = 119, [70.8%]) to decrease tumor size and thus to potentially allow a conservative surgical treatment. For these patients, MT was initially the only possible surgical treatment.

RESULTS

Among the 119 patients included, 118 presented with an invasive ductal carcinoma. The mean tumor size before nCT, measured using magnetic resonance imaging, was 41.6 mm (range, 15-110 mm) and 25.3 mm (range, 0-90 mm) after nCT. Eighty-six patients (72.3%) underwent BCS, and oncoplastic techniques were used in 29 patients (33.6%). Only 4.3% (5 patients) of patients who were treated with BCS needed additional surgery because of positive surgical margins. The median follow-up was 41.1 months (95% confidence interval [CI], 35.2-48.3). Five-year overall survival after BCS and MT were 77% (95% CI, 63-92) and 77% (95% CI, 63-95) respectively. Five-year disease-free survival after BCS and MT were 74% (95% CI, 64-86) and 59% (95% CI, 40-89) (not significant), respectively.

CONCLUSION

nCT for selective patients with "chemosensitive" breast tumor leads to a significant "MT to BCS" conversion rate. The type of surgery does not seem to affect the patient's overall and disease-free survival rates. Oncoplastic procedures can help to extend BCS after nCT.

Marginal activity of progesterone receptor B (PR-B) in dogs but high incidence of mammary cancer

Progesterone plays an important role in the normal development and carcinogenesis of the mammary gland. In vitro studies have shown that the canine progesterone receptor B (cPR-B), which is essential for mammary development in the mouse, does not transactivate reporter constructs containing progesterone response elements. Therefore, the question was raised whether the cPR-B was completely devoid of transactivation potential of endogenous progesterone regulated genes. Canine mammary cell lines expressing doxycycline-inducible cPR-B, human PR-B or a chimera in which the canine B-upstream segment (BUS) was replaced by a human BUS were treated for 24h with doxycycline, progesterone or a combination of the two. The expression profiling was subsequently performed using a dog-specific microarray and miRNA primers. Incubation of stably transfected cell lines with doxycycline or progesterone alone, did not change expression of any endogenous gene. Expression of activated human PR-B or the chimera of human BUS with the canine PR resulted in differential expression of >500 genes whereas the activated cPR-B regulated only a subset of 40 genes and to a limited extent. The relevance of the marginal transactivation potential or the consequence of a lack of cPR-B function for the carcinogenesis of mammary gland tumors is discussed.

Utilization of neoadjuvant chemotherapy varies in the treatment of women with invasive breast cancer

BACKGROUND

Treatment with neoadjuvant chemotherapy (NAC) has made it possible for some women to be successfully treated with breast conservation therapy (BCT ) who were initially considered ineligible. Factors related to current practice patterns of NAC use are important to understand particularly as the surgical treatment of invasive breast cancer has changed. The goal of this study was to determine variations in neoadjuvant chemotherapy use in a large multi-center national database of patients with breast cancer.

METHODS

We evaluated NAC use in patients with initially operable invasive breast cancer and potential impact on breast conservation rates. Records of 2871 women ages 18-years and older diagnosed with 2907 invasive breast cancers from January 2003 to December 2008 at four institutions across the United States were examined using the Breast Cancer Surgical Outcomes (BRCASO) database. Main outcome measures included NAC use and association with pre-operatively identified clinical factors, surgical approach (partial mastectomy [PM] or total mastectomy [TM]), and BCT failure (initial PM followed by subsequent TM).

RESULTS

Overall, NAC utilization was 3.8%l. Factors associated with NAC use included younger age, pre-operatively known positive nodal status, and increasing clinical tumor size. NAC use and BCT failure rates increased with clinical tumor size, and there was significant variation in NAC use across institutions. Initial TM frequency approached initial PM frequency for tumors >30-40 mm; BCT failure rate was 22.7% for tumors >40 mm. Only 2.7% of patients undergoing initial PM and 7.2% undergoing initial TM received NAC.

CONCLUSIONS

NAC use in this study was infrequent and varied among institutions. Infrequent NAC use in patients suggests that NAC may be underutilized in eligible patients desiring breast conservation.

Predictive factors determining neoadjuvant chemotherapy outcomes in breast cancer - a single center experience

From January 1, 2008 to March 31, 2010, 101 patients with stage II-III breast cancer were enrolled in this study and subjected to an anthracycline-based neoadjuvant chemotherapy regimen with or without docetaxel. Surgery was performed after 2-6 cycles of chemotherapy, and the clinical response was determined by pathological and histochemical assessments. The clinical response rate, as indicated by complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD), were 6.9, 52.5, 36.6, and 4.0%, respectively. A multivariable correlation analysis indicated that the overall clinical response rate correlated with the number of metastatic lymph nodes, number of chemotherapy cycles, and vessel invasion status. Importantly, the CR rate was only associated with the number of chemotherapy cycles. Nonparametric tests failed to detect a correlation between HER2 or Topo IIα status and clinical response to neoadjuvant chemotherapy in these patients. When they were stratified by HER2 or HR status, for HER2-positive patients the CR rate was associated with vessel invasion and Topo IIα status. Based on our findings, we propose that HR, HER-2 and Topo IIα are not putative predictive biomarkers of chemotherapy outcome for breast cancer patients. Topo IIα expression level was only inversely correlated with CR rate among HR-positive patients. Importantly, the achievement of CR was largely related to the number of chemotherapy cycles.

The role of oncoplastic breast surgery in the management of breast cancer treated with primary chemotherapy

OBJECTIVE

The purpose of this study was to evaluate the benefit of Oncoplastic Breast Conserving Surgery (BCS) compared to standard BCS after primary CT, in terms of oncologic safety and cosmetic outcomes.

BACKGROUND

The development of new drugs has led to greater use of primary chemotherapy (CT) for bulky breast cancer (BC) and has allowed wider indications for conservative surgery.

PATIENTS AND METHODS

We identified 259 patients consecutively treated with BCS for primary BC from January 2002 to November 2010. All patients had undergone Oncoplastic Breast Surgery (OBS) or standard BCS after primary CT. Mastectomy rates, and oncological and cosmetic outcomes were compared.

RESULTS

A total of 45 OBS and 214 standard BCS were analyzed. The median tumor size was 40 mm in the two groups (p = 0.66). The median operative specimen volumes were larger in the OBS group than in the standard group (respectively, 180 cm3 and 98 cm3, p < 0.0001). Re-excision (9% vs. 2%) and mastectomy (24% vs. 18%) rates were similar (p = 0.22 and p = 0.30) in the standard BCS group and in the OBS group respectively. At a median follow-up of 46 months, local relapse (p = 0.23) and distant relapse (p = 0.35) rates were similar.

CONCLUSION

OBS allows excision of larger volumes of residual tumor after primary CT. OBS outcomes results were similar to those of standard BCS. Oncoplastic Breast Conserving Surgery (BCS) after primary chemotherapy allows wider breast resection than standard BCS. Survival and relapse probabilities are similar in both groups.

Targeting the PI3K/AKT/mTOR and Raf/MEK/ERK pathways in the treatment of breast cancer

Alterations of signal transduction pathways leading to uncontrolled cellular proliferation, survival, invasion, and metastases are hallmarks of the carcinogenic process. The phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) and the Raf/mitogen-activated and extracellular signal-regulated kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathways are critical for normal human physiology, and also commonly dysregulated in several human cancers, including breast cancer (BC). In vitro and in vivo data suggest that the PI3K/AKT/mTOR and Raf/MEK/ERK cascades are interconnected with multiple points of convergence, cross-talk, and feedback loops. Raf/MEK/ERK and PI3K/AKT/mTOR pathway mutations may co-exist. Inhibition of one pathway can still result in the maintenance of signaling via the other (reciprocal) pathway. The existence of such "escape" mechanisms implies that dual targeting of these pathways may lead to superior efficacy and better clinical outcome in selected patients. Several clinical trials targeting one or both pathways are already underway in BC patients. The toxicity profile of this novel approach of dual pathway inhibition needs to be closely monitored, given the important physiological role of PI3K/AKT/mTOR and Raf/MEK/ERK signaling. In this article, we present a review of the current relevant pre-clinical and clinical data and discuss the rationale for dual inhibition of these pathways in the treatment of BC patients.

A systematic evaluation of multi-gene predictors for the pathological response of breast cancer patients to chemotherapy

Previous studies have reported conflicting assessments of the ability of cell line-derived multi-gene predictors (MGPs) to forecast patient clinical outcomes in cancer patients, thereby warranting an investigation into their suitability for this task. Here, 42 breast cancer cell lines were evaluated by chemoresponse tests after treatment with either TFAC or FEC, two widely used standard combination chemotherapies for breast cancer. We used two different training cell line sets and two independent prediction methods, superPC and COXEN, to develop cell line-based MGPs, which were then validated in five patient cohorts treated with these chemotherapies. This evaluation yielded high prediction performances by these MGPs, regardless of the training set, chemotherapy, or prediction method. The MGPs were also able to predict patient clinical outcomes for the subgroup of estrogen receptor (ER)-negative patients, which has proven difficult in the past. These results demonstrated a potential of using an in vitro-based chemoresponse data as a model system in creating MGPs for stratifying patients’ therapeutic responses. Clinical utility and applications of these MGPs will need to be carefully examined with relevant clinical outcome measurements and constraints in practical use.