Loco-regional treatment in metastatic breast cancer patients: Is there a survival benefit?

Obesity-Associated Breast Cancer: Analysis of Risk Factors and Current Clinical Evaluation

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Additionally, obese and postmenopausal women are at higher risk of all-cause and breast cancer-specific mortality compared with non-obese women with breast cancer. In this context, increased levels of estrogens, excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, adipocyte-derived adipokines, hypercholesterolemia, and excessive oxidative stress contribute to the development of breast cancer in obese women. Genetic evaluation is an integral part of diagnosis and treatment for patients with breast cancer. Despite trimodality therapy, the four-year cumulative incidence of regional recurrence is significantly higher. Axillary lymph nodes as well as primary lesions have diagnostic, prognostic, and therapeutic significance for the management of breast cancer. In clinical setting, because of the obese population primary lesions and enlarged lymph nodes could be less palpable, the diagnosis may be challenging due to misinterpretation of physical findings. Thereby, a nomogram has been created as the "Breast Imaging Reporting and Data System" (BI-RADS) to increase agreement and decision-making consistency between mammography and ultrasonography (USG) experts. Additionally, the "breast density classification system," "artificial intelligence risk scores," ligand-targeted receptor probes," "digital breast tomosynthesis," "diffusion-weighted imaging," "18F-fluoro-2-deoxy-D-glucose positron emission tomography," and "dynamic contrast-enhanced magnetic resonance imaging (MRI)" are important techniques for the earlier detection of breast cancers and to reduce false-positive results. A high concordance between estrogen receptor (ER) and progesterone receptor (PR) status evaluated in preoperative percutaneous core needle biopsy and surgical specimens is demonstrated. Breast cancer surgery has become increasingly conservative; however, mastectomy may be combined with any axillary procedures, such as sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection whenever is required. As a rule, SLNB-guided axillary dissection in breast cancer patients who have clinically axillary lymph node-positive to node-negative conversion following neoadjuvant chemotherapy is recommended, because lymphedema is the most debilitating complication after any axillary surgery. There is no clear consensus on the optimal treatment of occult breast cancer, which is much discussed today. Similarly, the current trend in metastatic breast cancer is that the main palliative treatment option is systemic therapy.

Role of Surgery in Metastatic Breast Cancer: Insights from a Narrative Review

Metastatic breast cancer is difficult to cure and has a worse prognosis with higher rates of mortality. Recently, breast surgery is believed to improve the survival rates among these women, but due to limited evidence, definite conclusions cannot be made. Therefore, we undertook this narrative review to synthesize the evidence from existing studies to assess the effectiveness of locoregional surgery and surgery of metastatic sites in improving the outcomes among women diagnosed with metastatic cancer disease along with the summary of current treatment guidelines. We reviewed PubMed and Embase and included both observational studies and randomized controlled trials (RCTs) that were published in English between 2000 and 2021. Outcomes were either survival, quality of life, toxicity related to local treatment assessed by mortality at the end of one month, progression-free survival, and breast cancer-specific survival. The main effect size assessed was hazard ratio with their 95% CIs. After literature search, we found 8 observational studies and 3 RCTs. The findings of the observational studies revealed that breast cancer surgery improves survival from 30% to 50% among women. However, findings from RCTs were mixed for local and distant progression survival. Surgery improved the local progression-free survival but worsened the distant progression-free survival. Besides, there was no effect of breast surgery on quality of life. Regarding the surgery of metastatic site, studies are complex with mixed findings and variation in survival depending upon the type of metastatic site and response to initial systematic therapy and other factors. Based on the existing mixed evidence, it is not possible to make firm and definite conclusions about the effectiveness of breast surgery in improving the survival or quality of life among women with metastatic breast cancer. In future, more RCTs are required with a larger sample size to confirm the findings of observational studies.

Is Surgical Management of Primary Beneficial in Metastatic Breast Cancer??

Metastatic breast cancer is not a curable disease, but women with metastatic disease are living longer. Although the relative survival has improved in recent years still patients who present with metastatic disease have a less than 30% 5-year survival. Historically, removal of the primary breast tumor has been offered to these patients only for palliation. However, there have been recent reports that removal of the primary tumor may improve survival. These are mostly retrospective studies limited by selection bias. Prospective and randomized trials have not shown a clear survival advantage. Although the definitive role of removal of the primary tumor in metastatic breast cancer is not settled, it is critical to understand the complexities of this debate in order to make further gains in breast cancer survivorship.

Palliative radiation therapy for symptomatic advance breast cancer

In this study, we evaluated the effectiveness of palliative breast radiation therapy (RT), with single fraction RT compared with fractionated RT. Our study showed that both RT fractionation schemas provide palliation. Single fraction RT allowed for treatment with minimal interference with systemic therapy, whereas fractionated RT provided a more durable palliative response. Due to equivalent palliative response, at our institution we have increasingly been providing single fraction RT palliation during the COVID-19 pandemic.

Axillary surgical approach in metastatic breast cancer patients: a systematic review and meta-analysis

A systematic review and meta-analysis were conducted to evaluate the benefit of an axillary surgical approach on overall survival and secondarily of breast surgery amongst patients with metastatic breast cancer which is considered to be an incurable disease. However, an axillary surgical approach showed no association with overall survival in patients with metastatic breast cancer. The true impact of locoregional therapies on long-term outcomes remains unknown, and randomised clinical trials are needed.

Role of surgery in patients with synchronous metastatic breast cancer: Is there a need for axillary lymph node removal?

INTRODUCTION

About 6% of women with breast cancer present with synchronous metastases. Treatment remains palliative in international recommendations but the impact of loco-regional surgery remains controversial.

OBJECTIVE

We conducted a multicentre, cohort study to evaluate the impact of axillary lymph node (ALN) surgery on overall survival in stage IV breast cancer at diagnosis.

METHODS

Patients presenting with breast cancer and synchronous metastases between 2005 and 2014 were included. Follow up was conducted up to 1st June 2018. The only exclusion criterion was a history of previous malignancies. Breast surgery was defined as lumpectomy or mastectomy. Axillary surgery included full ALN dissection, and sentinel lymph node biopsy (SLNB). If the SLN was invaded on the frozen section, full axillary dissection was performed.

RESULTS

152 patients were included. 71 women had no surgery, 81 had primary site surgery of which 64 (79%) had breast and axillary surgery and 17 (21%) breast surgery only. 5-year overall survival was 59.8% (95% CI=[49.5; 69.5]) for women with breast and axillary surgery, 23.5% (95% CI=[15.6; 33]) for women with breast surgery only and 9.8% (95% CI=[4.7; 17.5]) for women without any surgery, p < 0.001. Combined with breast surgery, axillary surgery significantly added a mean of 33 months to patient overall survival.

CONCLUSION

ALN surgery combined with breast surgery in metastatic breast cancer significantly increased overall survival. Thus surgical indications should not differ from those in women with breast cancer without metastases.

Locoregional surgical treatment improves the prognosis in primary metastatic breast cancer patients with a single distant metastasis except for brain metastasis

BACKGROUND

We aimed to validate the clinical significance of locoregional surgery in improving the prognosis of primary metastatic breast cancer (pMBC).

METHODS

We conducted a population-based retrospective study by analyzing clinical data obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. Stratification analysis was employed to assess the effect of breast surgery on breast cancer-specific survival and overall survival. Then propensity score matching and COX regression models were employed to evaluate the survival advantages of breast surgery, if any in patients with pMBC.

RESULTS

The median BCSS and OS in the surgery group were almost twice of that in the group without surgery. Breast surgery provided a survival advantage for patients with a single metastasis in the bone, liver or lung, but not in the brain. We found that axillary lymph node dissection performed in combination with specific breast surgical procedures did not result in a significant improvement in survival. Additionally, when combined with radiotherapy and/or chemotherapy, surgery significantly improved the survival and was not influenced by the molecular subtype and tumor size. Finally, using COX regression models before and after propensity score matching, breast surgery was found to reduce the risk of mortality in patients with MBC by more than 40%.

CONCLUSIONS

The effect of locoregional surgery has been underestimated in pMBC patients. Surgical procedures should be seriously considered when planning combination treatments for pMBC patients with a single metastasis except for brain metastasis.

Lymph node metastases can invade local blood vessels, exit the node, and colonize distant organs in mice

Lymph node metastases in cancer patients are associated with tumor aggressiveness, poorer prognoses, and the recommendation for systemic therapy. Whether cancer cells in lymph nodes can seed distant metastases has been a subject of considerable debate. We studied mice implanted with cancer cells (mammary carcinoma, squamous cell carcinoma, or melanoma) expressing the photoconvertible protein Dendra2. This technology allowed us to selectively photoconvert metastatic cells in the lymph node and trace their fate. We found that a fraction of these cells invaded lymph node blood vessels, entered the blood circulation, and colonized the lung. Thus, in mouse models, lymph node metastases can be a source of cancer cells for distant metastases. Whether this mode of dissemination occurs in cancer patients remains to be determined.

Breast surgery for metastatic breast cancer

BACKGROUND

Metastatic breast cancer is not a curable disease, but women with metastatic disease are living longer. Surgery to remove the primary tumour is associated with an increased survival in other types of metastatic cancer. Breast surgery is not standard treatment for metastatic disease, however several recent retrospective studies have suggested that breast surgery could increase the women's survival. These studies have methodological limitations including selection bias. A systematic review mapping all randomised controlled trials addressing the benefits and potential harms of breast surgery is ideal to answer this question.

OBJECTIVES

To assess the effects of breast surgery in women with metastatic breast cancer.

SEARCH METHODS

We conducted searches using the MeSH terms 'breast neoplasms', 'mastectomy', and 'analysis, survival' in the following databases: the Cochrane Breast Cancer Specialised Register, CENTRAL, MEDLINE (by PubMed) and Embase (by OvidSP) on 22 February 2016. We also searched ClinicalTrials.gov (22 February 2016) and the WHO International Clinical Trials Registry Platform (24 February 2016). We conducted an additional search in the American Society of Clinical Oncology (ASCO) conference proceedings in July 2016 that included reference checking, citation searching, and contacting study authors to identify additional studies.

SELECTION CRITERIA

The inclusion criteria were randomised controlled trials of women with metastatic breast cancer at initial diagnosis comparing breast surgery plus systemic therapy versus systemic therapy alone. The primary outcomes were overall survival and quality of life. Secondary outcomes were progression-free survival (local and distant control), breast cancer-specific survival, and toxicity from local therapy.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted trial selection, data extraction, and 'Risk of bias' assessment (using Cochrane's 'Risk of bias' tool), which a third review author checked. We used the GRADE tool to assess the quality of the body of evidence. We used the risk ratio (RR) to measure the effect of treatment for dichotomous outcomes and the hazard ratio (HR) for time-to-event outcomes. We calculated 95% confidence intervals (CI) for these measures. We used the random-effects model, as we expected clinical or methodological heterogeneity, or both, among the included studies.

MAIN RESULTS

We included two trials enrolling 624 women in the review. It is uncertain whether breast surgery improves overall survival as the quality of the evidence has been assessed as very low (HR 0.83, 95% CI 0.53 to 1.31; 2 studies; 624 women). The two studies did not report quality of life. Breast surgery may improve local progression-free survival (HR 0.22, 95% CI 0.08 to 0.57; 2 studies; 607 women; low-quality evidence), while it probably worsened distant progression-free survival (HR 1.42, 95% CI 1.08 to 1.86; 1 study; 350 women; moderate-quality evidence). The two included studies did not measure breast cancer-specific survival. Toxicity from local therapy was reported by 30-day mortality and did not appear to differ between the two groups (RR 0.99, 95% CI 0.14 to 6.90; 1 study; 274 women; low-quality evidence).

AUTHORS' CONCLUSIONS

Based on existing evidence from two randomised clinical trials, it is not possible to make definitive conclusions on the benefits and risks of breast surgery associated with systemic treatment for women diagnosed with metastatic breast cancer. Until the ongoing clinical trials are finalised, the decision to perform breast surgery in these women should be individualised and shared between the physician and the patient considering the potential risks, benefits, and costs of each intervention.

Lx2-32c-loaded polymeric micelles with small size for intravenous drug delivery and their inhibitory effect on tumor growth and metastasis in clinically associated 4T1 murine breast cancer

Lx2-32c is a novel taxane derivative with a strong antitumor activity. In this study, we developed Lx2-32c–loaded polymeric micelles (Lx2-32c-PMs) with small size and investigated their antitumor efficacy against tumor growth and metastasis on 4T1 murine breast cancer cell line with Cremophor EL–based Lx2-32c solution as the control. In this study, copolymer monomethoxy polyethylene glycol₂₀₀₀–polylactide₁₃₀₀ was used to prepare Lx2-32c-PMs by film hydration method, and their physicochemical properties were characterized as well, according to morphology, particle size, zeta potential, in vitro drug release, and reconstitution stability. Under confocal laser scanning microscopy, it was observed that Lx2-32c-PMs could be effectively taken up by 4T1 cells in a time-dependent manner. Cell Counting Kit-8 assay showed that the IC₅₀ of Lx2-32c-PMs was 0.3827 nM. Meanwhile, Lx2-32c-PMs had better ability to promote apoptosis and induce G₂/M cycle block and polyploidy formation, compared with Lx2-32c solution. More importantly, in vivo animal studies showed that compared to Lx2-32c solution, Lx2-32c-PMs possessed better ability not only to effectively inhibit the tumor growth, but also to significantly suppress spontaneous and postoperative metastasis to distant organs in 4T1 orthotopic tumor-bearing mice. Consequently, Lx2-32c-PMs have significantly prolonged the survival lifetime of tumor-bearing mice. Thus, our study reveals that Lx2-32c-PMs had favorable antitumor activity and exhibited a good prospect for application in the field of antitumor therapy.

Time trends in incidence rates and survival of newly diagnosed stage IV breast cancer by tumor histology: a population-based analysis

Few contemporary data are available that compare incidence and survival of metastatic breast cancer between ductal and lobular carcinomas. Using the Surveillance, Epidemiology, and End Results-9 registries, we identified 10,639 patients with de novo metastatic breast cancer diagnosed from 1990 to 2011. Annual age-adjusted incidence rates and annual percent changes (APCs) were analyzed. Multivariable Cox regression models were used to investigate the impact of year of diagnosis and histology on overall survival. 9250 (86.9 %) patients had ductal and 1389 (13.1 %) had lobular carcinomas. Metastatic breast cancer incidence increased slightly over time for ductal (APC = +1.7, 95 % confidence interval (CI) = +1.0 to +2.4) and lobular carcinomas (APC = +3.0, 95 % CI = +1.8 to +4.3). Median overall survival was 22 months among the whole cohort. More recent year of diagnosis was associated with better overall survival only for patients with ductal carcinomas (interaction p value = 0.006), with an adjusted hazard ratio of death for every five-year increment in the date of diagnosis of 0.93 (95 % CI =  0.91-0.95) among ductal carcinomas, compared with 1.05 (95 % CI = 0.95-1.10) among lobular carcinomas. Overall survival was longer for lobular versus ductal carcinomas (28 versus 21 months, respectively; adjusted hazard ratio of death = 0.93, 95 % CI = 0.87-0.99), but the magnitude of this effect was attenuated among the cohort restricted to hormone receptor-positive tumors. In this population-based analysis, incidence rates of metastatic breast cancer at presentation increased slightly over time for both histologies, and particularly for lobular tumors. A modest improvement in metastatic breast cancer median overall survival was observed, but was apparently limited to ductal carcinomas.

Willingness of Patients with Breast Cancer in the Adjuvant and Metastatic Setting to Use Electronic Surveys (ePRO) Depends on Sociodemographic Factors, Health-related Quality of Life, Disease Status and Computer Skills

Introduction: Because of the often unfavorable prognosis, particularly for patients with metastases, health-related quality of life is extremely important for breast cancer patients. In recent years, data on patient-relevant endpoints is being increasingly collected electronically; however, knowledge on the acceptance and practicability of, and barriers to, this form of data collection remains limited. Material and Methods: A questionnaire was completed by 96 patients to determine to what extent existing computer skills, disease status, health-related quality of life and sociodemographic factors affect patients' potential willingness to use electronics methods of data collection (ePRO). Results: 52 of 96 (55 %) patients reported a priori that they could envisage using ePRO. Patients who a priori preferred a paper-based survey (pPRO) tended to be older (ePRO 53 years vs. pPRO 62 years; p = 0.0014) and typically had lower levels of education (p = 0.0002), were in poorer health (p = 0.0327) and had fewer computer skills (p = 0.0003). Conclusion: Barriers to the prospective use of ePRO were identified in older patients and patients with a lower quality of life. Given the appropriate conditions with regard to age, education and current health status, opportunities to participate should be provided to encourage patients' willingness to take part and ensure the validity of survey results. Focusing on ease of use of ePRO applications and making applications more patient-oriented and straightforward appears to be the way forward.

Surgical Management of de novo Stage IV Breast Cancer

The natural history of stage IV breast cancer is changing, with diagnosis when the disease burden is lower and better drugs translating into longer survival. Nevertheless, a small but constant fraction of women present with de novo stage IV disease and an intact primary tumor. The management of the primary site in this setting has classically been determined by the presence of symptoms, but this approach has been questioned based on multiple retrospective reviews reported over the past decade that suggested a survival advantage for women whose intact primary tumor is resected. These reviews are necessarily biased, as younger women with lower disease burden and more favorable biological features were offered surgery, but they led to several randomized trials to test the value of local therapy for the primary tumor in the face of distant disease. Preliminary results from 2 of these do not support a significant survival benefit, although local control benefits may exist. Completion of ongoing trials is needed to reach a definitive conclusion regarding the merit of primary tumor resection for local control and survival. Until unbiased data are available, local therapy for asymptomatic primary tumors cannot be recommended in the expectation of a survival benefit.

Surgery of the primary tumor in de novo metastatic breast cancer: To do or not to do?

Approximately five percent of all breast cancer patients in developed countries present with distant metastases at initial diagnosis. Due to its incurability, metastatic breast cancer is generally treated with systemic therapies to achieve disease control and reduce tumor-related symptoms. Primary treatments for metastatic breast cancer are chemotherapy, endocrine- and biologic therapy, whereas surgery with or without radiotherapy is usually performed to treat impending wound issues. Since 2002, several retrospective non-randomized clinical studies have shown that extirpation of the primary tumor correlates with a significantly improved survival in patients with primary metastatic breast cancer. Others have argued that this survival benefit associated with surgery may be due to selection biases. Therefore, in the absence of published results from randomized controlled trials carried out in India and Turkey and completion of a trial in the United States, there is no clear conclusion on whether surgical excision of the primary breast cancer translates into a survival benefit for patients with de novo metastatic disease. Furthermore, timing and type of surgical procedure, as well as selection of patients who could benefit the most from this approach, represent additional points of uncertainty. Despite the epidemiological burden of this condition, there are no guidelines on how to manage breast cancer patients presenting with de novo metastatic breast cancer; and decisions are often left to provider and patient preferences. Here, we present a critical overview of the literature focusing on the rationale and potential role of primary tumour excision in patients with de novo metastatic breast cancer.

Risk of treatment related death and febrile neutropaenia with first line palliative chemotherapy for de novo metastatic breast cancer in clinical practice in a middle resource country

BACKGROUND

The risk of febrile neutropaenia (FN) and treatment related death (TRD) with first line palliative chemotherapy for de novo metastatic breast cancer (MBC) remains unknown outside of a clinical trial setting despite its widespread usage. This study aimed to determine rates in a large cohort of patients treated in the University of Malaya Medical Centre (UMMC).

MATERIALS AND METHODS

Patients who were treated with first line palliative chemotherapy for de novo MBC from 2002-2011 in UMMC were identified from the UMMC Breast Cancer Registry. Information collected included patient demographics, histopathological features, treatment received, including the different chemotherapy regimens, and presence of FN and TRD. FN was defined as an oral temperature >38.5° or two consecutive readings of >38.0° for 2 hours and an absolute neutrophil count <0.5x109/L, or expected to fall below 0.5x109/L (de Naurois et al, 2010). TRD was defined as death occurring during or within 30 days of the last chemotherapy treatment, as a consequence of the chemotherapy treatment. Statistical analysis was performed using the SPSS version 18.0 software. Survival probabilities were estimated using the Kaplan-Meier method and differences in survival compared using log-rank test.

RESULTS

Between 1st January 2002 and 31st December 2011, 424 patients with MBC were treated in UMMC. A total of 186 out of 221 patients with de novo MBC who received first line palliative chemotherapy were analyzed. The mean age of patients in this study was 49.5 years (range 24 to 74 years). Biologically, ER status was negative in 54.4% of patients and Her-2 status was positive in 31.1%. A 5-flourouracil, epirubicin and cyclophosphamide (FEC) chemotherapy regimen was chosen for 86.6% of the cases. Most patients had multiple metastatic sites (58.6%). The main result of this study showed a FN rate of 5.9% and TRD rate of 3.2%. The median survival (MS) for the entire cohort was 19 months. For those with multiple metastatic sites, liver only, lung only, bone only and brain only metastatic sites, the MS was 18, 24, 19, 24 and 8 months respectively (p-value= 0.319).

CONCLUSIONS

In conclusion, we surmise that FEC is a safe regimen with acceptable FN and TRD rates for de novo MBC.

Neighborhood socioeconomic deprivation, tumor subtypes, and causes of death after non-metastatic invasive breast cancer diagnosis: a multilevel competing-risk analysis

The purpose of this study is to examine the associations of neighborhood socioeconomic deprivation and triple-negative breast cancer (TNBC) subtype with causes of death [breast cancer (BC)-specific and non-BC-specific] among non-metastatic invasive BC patients. We identified 3,312 patients younger than 75 years (mean age 53.5 years; 621 [18.8 %] TNBC) with first primary BC treated at an academic medical center from 1999 to 2010. We constructed a census-tract-level socioeconomic deprivation index using the 2000 U.S. Census data and performed a multilevel competing-risk analysis to estimate the hazard ratios (HR) and 95 % confidence intervals (CI) of BC-specific and non-BC-specific mortality associated with neighborhood socioeconomic deprivation and TNBC subtype. The adjusted models controlled for patient sociodemographics, health behaviors, tumor characteristics, comorbidity, and cancer treatment. With a median 62-month follow-up, 349 (10.5 %) patients died; 233 died from BC. In the multivariate models, neighborhood socioeconomic deprivation was independently associated with non-BC-specific mortality (the most- vs. the least-deprived quartile: HR = 2.98, 95 % CI = 1.33-6.66); in contrast, its association with BC-specific mortality was explained by the aforementioned patient-level covariates, particularly sociodemographic factors (HR = 1.15, 95 % CI = 0.71-1.87). TNBC subtype was independently associated with non-BC-specific mortality (HR = 2.15; 95 % CI = 1.20-3.84), while the association between TNBC and BC-specific mortality approached significance (HR = 1.42; 95 % CI = 0.99-2.03, P = 0.057). Non-metastatic invasive BC patients who lived in more socioeconomically deprived neighborhoods were more likely to die as a result of causes other than BC compared with those living in the least socioeconomically deprived neighborhoods. TNBC was associated with non-BC-specific mortality but not BC-specific mortality.

Bilateral synchronous adrenal metastasis of invasive ductal carcinoma treated with multimodality therapy including adrenalectomy and oophorectomy

A 38-year-old woman presented with a mass in the left breast. Biopsy of the lesion revealed invasive ductal carcinoma. Bilateral adrenal metastasis was detected in whole body positron emission tomography scanning. Needle biopsy of the left adrenal lesion proved infiltration of malignant cells from breast carcinoma. After eight cycles of neoadjuvant (preoperative) chemotherapy, mastectomy, bilateral adrenalectomy, and bilateral oopherectomy were performed. No further hormonal treatment was recommended due to the resection of both adrenal glands and ovaries. The patient is still followed without any sign of progression. To our knowledge, this is the first case representing multimodality approach to breast cancer with bilateral synchronous adrenal metastasis. Patients with oligometastatic disease may benefit from aggressive treatment including local therapies.

De novo Stage IV breast cancer: breast conserving resection of the primary tumor?

Multiple retrospective reviews completed over the past decade suggest a survival advantage with resection of the intact primary tumor in women with metastatic breast cancer. However, these reviews are not without bias, and recently completed randomized trials do not support a significant survival benefit, although local control benefits may exist. Completion of ongoing trials is needed to reach a definitive conclusion regarding the merit of primary tumor resection for local control and survival.

Predicting survival of de novo metastatic breast cancer in Asian women: systematic review and validation study

Background

In Asia, up to 25% of breast cancer patients present with distant metastases at diagnosis. Given the heterogeneous survival probabilities of de novo metastatic breast cancer, individual outcome prediction is challenging. The aim of the study is to identify existing prognostic models for patients with de novo metastatic breast cancer and validate them in Asia.

Materials and Methods

We performed a systematic review to identify prediction models for metastatic breast cancer. Models were validated in 642 women with de novo metastatic breast cancer registered between 2000 and 2010 in the Singapore Malaysia Hospital Based Breast Cancer Registry. Survival curves for low, intermediate and high-risk groups according to each prognostic score were compared by log-rank test and discrimination of the models was assessed by concordance statistic (C-statistic).

Results

We identified 16 prediction models, seven of which were for patients with brain metastases only. Performance status, estrogen receptor status, metastatic site(s) and disease-free interval were the most common predictors. We were able to validate nine prediction models. The capacity of the models to discriminate between poor and good survivors varied from poor to fair with C-statistics ranging from 0.50 (95% CI, 0.48–0.53) to 0.63 (95% CI, 0.60–0.66).

Conclusion

The discriminatory performance of existing prediction models for de novo metastatic breast cancer in Asia is modest. Development of an Asian-specific prediction model is needed to improve prognostication and guide decision making.

Breast cancer subtypes: response to radiotherapy and potential radiosensitisation

Radiotherapy (RT) is of critical importance in the locoregional management of early breast cancer. Over 50% of patients receive RT at some time during the treatment of their disease, equating to over 500 000 patients worldwide receiving RT each year. Unfortunately, not all patients derive therapeutic benefit and some breast cancers are resistant to treatment, as evidenced by distant metastatic spread and local recurrence. Prediction of individual responses to RT may allow a stratified approach to this treatment permitting those patients with radioresistant tumours to receive higher doses of RT (total and/or tumour cavity boost doses) and/or radiosensitising agents to optimise treatment. Also, for those patients unlikely to respond at all, it would prevent harmful side effects occurring for no therapeutic gain. More selective targeting would better direct National Health Service resources, ease the burden on heavily used treatment RT machines and reduce the economic cost of cancer treatment. Unfortunately, there are no robust and validated biomarkers for predicting RT outcome. We review the available literature to determine whether classification of breast cancers according to their molecular profile may be used to predict successful response to, or increased morbidity from, RT. Class-specific biomarkers for targeting by radiosensitising agents are also discussed.

Surgery of primary tumors in stage IV breast cancer: an updated meta-analysis of published studies with meta-regression

Systemic therapy is the mainstream treatment of stage IV breast cancer. Surgical excision of the primary breast cancer tumor in the presence of synchronous metastatic disease is debated, but a shared indication is not proposed by current guidelines. The purpose of this analysis is to aggregate the published survival data of surgery of an intact primary tumor in stage IV disease. The authors searched PubMed for publications reporting data about the survival benefit of surgery of the primary tumor in patients with metastatic breast cancer. Hazard ratios for survival when reported after multivariate analysis (with 95 % confidence intervals) were obtained from publications and pooled in a meta-analysis. A meta-regression weighted for the extent of disease, ER/HER2 status, age, visceral or bone disease, rate of radiotherapy, and systemic therapies offered was performed. A total of 15 publications were included in this meta-analysis. Surgery of the primary tumor appeared to be an independent factor for an improved survival in the multivariate analyses from the individual studies, with an HR of 0.69 (p < 0.00001). According to meta-regression, the survival benefit was independent of age, extent, site of the metastatic disease, and HER2 status, but was directly proportional to the rate of patients exposed to systemic therapies and radiotherapy and inversely correlated with the ER+ status of the population included. Surgery of the primary tumor in stage IV breast cancer seems to offer a survival benefit in metastatic patients, in particular when it is offered in a multimodality treatment program.

Discrepancies between primary tumor and metastasis: a literature review on clinically established biomarkers

The identification of predictive factors of response is critical for the development and appropriate use of anti-cancer agents. The evaluation of biomarkers is usually performed by analyzing the primary tumor tissues but this approach does not take into account potential discrepancies between primary tumor and secondary lesions. This review proposes to describe currently available data regarding differential expression of established biomarkers between primary tumor and matched metastasis. In light of recent data, the need of iterative biopsies in metastatic setting has been suggested but technical and methodological limits in such analyses should not be ignored and this strategy cannot be definitively validated. Complementary studies are still needed since the question of spatial and temporal variability of biomarkers in solid tumors is clearly a key issue in an era where personalized therapy is strongly advocated by clinicians, researchers and patients.

SUBMIT: Systemic therapy with or without up front surgery of the primary tumor in breast cancer patients with distant metastases at initial presentation

BACKGROUND

Five percent of all patients with breast cancer have distant metastatic disease at initial presentation. Because metastatic breast cancer is considered to be an incurable disease, it is generally treated with a palliative intent. Recent non-randomized studies have demonstrated that (complete) resection of the primary tumor is associated with a significant improvement of the survival of patients with primary metastatic breast cancer. However, other studies have suggested that the claimed survival benefit by surgery may be caused by selection bias. Therefore, a randomized controlled trial will be performed to assess whether breast surgery in patients with primary distant metastatic breast cancer will improve the prognosis.

DESIGN

Randomization will take place after the diagnosis of primary distant metastatic breast cancer. Patients will either be randomized to up front surgery of the breast tumor followed by systemic therapy or to systemic therapy, followed by delayed local treatment of the breast tumor if clinically indicated.Patients with primary distant metastatic breast cancer, with no prior treatment of the breast cancer, who are 18 years or older and fit enough to undergo surgery and systemic therapy are eligible. Important exclusion criteria are: prior invasive breast cancer, surgical treatment or radiotherapy of this breast tumor before randomization, irresectable T4 tumor and synchronous bilateral breast cancer. The primary endpoint is 2-year survival. Quality of life and local tumor control are among the secondary endpoints.Based on the results of prior research it was calculated that 258 patients are needed in each treatment arm, assuming a power of 80%. Total accrual time is expected to take 60 months. An interim analysis will be performed to assess any clinically significant safety concerns and to determine whether there is evidence that up front surgery is clinically or statistically inferior to systemic therapy with respect to the primary endpoint.

DISCUSSION

The SUBMIT study is a randomized controlled trial that will provide evidence on whether or not surgery of the primary tumor in breast cancer patients with metastatic disease at initial presentation results in an improved survival.

TRIAL REGISTRATION

NCT01392586.