Fulvestrant and male breast cancer: a pooled analysis

Male breast cancer differs from female breast cancer in molecular features that affect prognoses and drug responses

BACKGROUND

Male breast cancer (MBC) is a rare malignancy with a worse prognosis than female breast cancer (FBC). Current MBC treatment strategies are based on those for FBC. However, molecular differences between MBC and FBC with respect to prognosis and drug responses remain unclear.

METHODS

After controlling for confounding factors with propensity score matching (PSM), differences between MBC and FBC were comprehensively analyzed using many types of data: survival, immune microenvironments, sex hormone responses, drug sensitivity, transcriptomes, genomes, epigenomes, and proteomes.

RESULTS

Overall survival (OS) and cancer-specific survival (CSS) were both worse for MBC than for FBC. Differentially expressed mRNAs were enriched in numerous cancer-related functions and pathways, with SPAG16 and STOX1 being as the most important prognosis-related mRNAs for MBC. Competing endogenous RNA (ceRNA) and transcription factor (TF)-mRNA regulatory networks contain potential prognostic genes. Nine genes had higher mutation frequencies in MBC than in FBC. MBC shows a comparatively poor response to immunotherapy, with five proteins that promote breast cancer progression being highly expressed in MBC. MBC may be more responsive than FBC to estrogen. We detected six United States Food and Drug Administration (FDA)-approved therapeutic target genes as being differentially expressed between MBC and FBC.

CONCLUSION

The poor prognosis of MBC compared to FBC is due to numerous molecular differences and resulting drug responses.

Male Breast Cancer: a Review on Diagnosis, Treatment, and Survivorship

PURPOSE OF REVIEW

Male breast cancer is a relatively uncommon and rare disease that is often managed based on evidence adopted from trials pertaining to female breast cancer due to low accrual rates or exclusion of males. This is despite the known differences in the biology and epidemiology of this condition. This review provides an update regarding the management and surveillance of male breast cancer.

RECENT FINDINGS

Men with breast cancer tend to undergo more extensive surgery in the breast and axilla. The outcomes of male breast cancer compared to a similar subtype of female breast cancer appear worse when matched for stage. Systemic therapies remain predominantly based on recommendations for female breast cancer, although tamoxifen is the more optimal endocrine therapy for men than women. Surveillance with mammograms is recommended for patients harboring a breast cancer susceptibility gene but is otherwise not advised for men who have undergone a mastectomy. Notably, the role of other imaging modalities, including ultrasound and magnetic resonance imaging, is minimal. Although the focus on survivorship care among men is low, it is abundantly clear that this is a stigmatizing diagnosis for men, and they suffer from long-term physical and psychological sequelae following a diagnosis and treatment of breast cancer. In summary, providing more gender-inclusive care and advocating for increased representation of men in prospective breast cancer studies and clinical trials may help improve outcomes and provide enhanced support for this population.

Unfolding the role of the PI3K/AKT/MTOR pathway in male breast cancer: A pragmatic appraisal

Breast cancer in men is rare, but a relevant public health issue, yielding a 25% higher risk of mortality comparing to female counterparts. The representation of males in clinical trials has been scarce and treatment decisions are based mainly on extrapolations from data in females. In the setting of estrogen-dependent metastatic disease, the use of everolimus has been seldom reported, although the PI3K/AKT/mTOR pathway seems to be a critical oncogenic driver. This paper dissects hallmark biological features of ER+/HER2-advanced male breast cancer, setting a comprehensive basis to promote personalized care, focusing on the potential of targeting the PI3K/AKT/mTOR pathway.

Case Series Analysis of Male Breast Cancer

Male breast cancer is a rare disease, accounting for less than 1% of all cases of breast cancer. However, the incidence of male breast cancer is increasing. In this study, we systematically analyzed the cases of male breast cancer and evaluated the management of operable male breast cancer in daily clinical practice according to the international clinical guidelines. Data of male breast cancer characteristics and management were recorded from our electronic database. We present a case series of male breast cancer patients treated at our institution between 2013 and 2021 and summarize the recommendations on management of male patients with breast cancer. Twenty-six patients met the search criteria. The majority of tumors were hormone-receptor positive and human epidermal growth factor receptor 2 negative. Two tumors were derived from axillary accessory breast. All patients underwent mastectomy. Fifteen patients received adjuvant chemotherapy containing anthracycline or taxane. Ten patients received adjuvant radiotherapy for lymph node metastasis. Twenty-five patients received adjuvant endocrine therapy. None of patients received anti-human epidermal growth factor receptor 2 therapy. During the median follow-up period of 37 months, one patient died of previous lung cancer recurrence and one patient developed lung metastases 2 years after breast surgery. No recurrence or distant metastasis occurred in the other twenty-four patients. The incidence of male breast cancer is low. In this study, we present twenty-six cases of male patients with operable breast cancer in our department. All of them received surgery and adjuvant treatment. Early diagnosis and combined therapy benefit male patients with breast cancer. Surgery together with adjuvant treatment can bring a good prognosis.

Male Breast Cancer: An Updated Review of Epidemiology, Clinicopathology, and Treatment

Male breast cancer (MaBC) is a rare clinical entity, which makes up approximately 1% of all breast cancers. However, the incidence of MaBC has been steadily increasing over the past few decades. The risk factors for MaBC include age, black race, family history of breast cancer, genetic mutations, liver cirrhosis, and testicular abnormalities. The majority of patients with MaBC present with painless lumps, and about half of the patients have at least one lymph node involved at the time of diagnosis. The treatment of MaBC models that of female breast cancer (FeBC), but this is mainly due to lack of prospective studies for MaBC patients. The treatment modality includes surgery, adjuvant radiation, endocrine therapy, and chemotherapy. However, there are some distinct features of MaBC, both clinically and molecularly, that may warrant a different clinical approach. Ongoing multinational effort is required, to conduct clinical trials for MaBC, or the inclusion of MaBC patients in FeBC trials, to help clinicians improve care for MaBC patients.

Bone Health Considerations in Breast Cancer

OBJECTIVES

The treatment of breast cancer requires the use of multiple modalities to achieve local control of disease and to prevent distant recurrence. Among patients whose tumors are hormone-receptor positive, endocrine therapy for up to 10 years in the adjuvant setting can be an important component of such therapy, but it is not without adverse events. Ovarian suppression or estrogen restriction can have a rapid and clinically significant detrimental effect on bone mineral density, leading to potential osteoporotic fracture. This article reviews the major causes of breast cancer treatment-induced bone loss and pharmacologic and nonpharmacologic management strategies to maintain bone health in this population.

DATA SOURCES

PubMed and international clinical practice guidelines were used.

CONCLUSION

A holistic, long-term approach is needed to identify and offer early intervention to patients at high-risk of significant bone density loss. A combination of routine screening, use of oral or intravenous bone-modifying agents, oral supplementation of calcium and vitamin D, and physical activity, including weight-bearing exercise, are required to maintain adequate bone health during treatment for breast cancer.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses are well-situated in the primary and survivorship care teams for patients with breast cancer to provide proactive education on the need to assess and actively manage bone health. Nonpharmacologic interventions such as dietary supplementation and physical activity are essential to health promotion and are within the nursing scope of practice to emphasize with this patient population.

A biomarker study in Peruvian males with breast cancer

BACKGROUND

Breast cancer (BC) frequency in males is extremely low and tumor features vary from its female counterpart. Breast cancer clinical and pathological features differ by race in women. Tumor infiltrating lymphocyte (TIL) levels, mismatch repair (MMR) protein loss, androgen receptor (AR) expression, and PIK3CA gene mutations are predictive biomarkers of response to biological therapy in female BC. There is limited information about clinical and pathological features as well as predictive biomarkers in males of non-Caucasian races with BC.

AIM

To investigate clinicopathological features and biomarkers of BC tumors in males and their prognostic value in Peruvian population.

METHODS

This study looked at a single-institution series of 54 Peruvian males with invasive BC who were diagnosed from Jan 2004 to June 2018. Standard pathological features, TIL levels, MMR proteins, AR immunohistochemistry staining, and PIK3CA gene mutations were prospectively evaluated in cases with available paraffin material. Percentage of AR and estrogen receptor (ER) positive cells was additionally calculated by software after slide scanning. Statistical analyses included association tests, intraclass correlation test and Kaplan Meier overall survival curves.

RESULTS

The median age was 63 years and most cases were ER-positive (85.7%), HER2 negative (87.2%), Luminal-A phenotype (60%) and clinical stage II (41.5%) among our male breast tumors. Median TIL was 10% and higher levels tended to be associated with Luminal-B phenotype and higher grade. AR-positive was found in 85.3% and was correlated with ER (intraclass index of 0.835, P < 0.001). Loss of MMR proteins was found in 15.4% and PIK3CA mutation (H1047R) in 14.3% (belonged to the Luminal-A phenotype). Loss of MMR proteins was associated with AR-negative (P = 0.018) but not with ER (P = 0.43) or TIL (P = 0.84). Early stages (P < 0.001) and lower grade (P = 0.006) were associated with longer overall survival. ER status, phenotype, AR status, TIL level, MMR protein loss nor PIK3CA mutation was not associated with survival (P > 0.05).

CONCLUSION

Male BC is usually ER and AR positive, and Luminal-A. MMR loss and PIK3CA mutations are infrequent. Stage and grade predicted overall survival in our South American country population.

A practical guide to endocrine therapy in the management of estrogen receptor-positive male breast cancer

The majority (more than 90%) of male breast cancers (MaBCs) are estrogen receptor-positive, such that endocrine therapy is the mainstay of MaBC treatment. Endocrine therapy has been associated with improved overall survival in observational studies on MaBC, though large randomized clinical trials have never been completed to confirm this benefit in this population. Tamoxifen is currently the preferred drug for both metastatic and adjuvant treatment of MaBC. Known differences in treatment patterns and hormonal milieu between men and women may warrant a unique approach to the management of toxicities in men. This review provides a detailed discussion of endocrine therapy for MaBC.

An updated review of epidemiology, risk factors, and management of male breast cancer

Unlike female breast cancer, male breast cancer (MBC) is rare and not very well understood. Prospective data in the management of MBC are lacking and majority of treatment strategies are adopted from the established guidelines for breast cancer in women. The understanding of biology, clinical presentation, genetics, and management of MBC is evolving but there still remains a large knowledge gap due to the rarity of this disease. Older age, high estradiol levels, klinefelter syndrome, radiation exposure, gynecomastia, family history of breast cancer, BRCA2 and BRCA1 mutation are some of the known risk factors for MBC. Routine screening mammography is not recommended for asymptomatic men. Diagnostic mammogram with or without ultrasound should be considered if there is a suspicion for breast mass. Majority of men with early-stage breast cancer undergo mastectomy whereas breast conserving surgery (BCS) with sentinel lymph node biopsy (SLNB) remains an alternative option in selected cases. Since the majority of MBC are hormone receptor positive (HR+), adjuvant hormonal therapy is required. Tamoxifen for a total of 5 to 10 years is the mainstay adjuvant hormonal therapy. The role of neoadjuvant and adjuvant chemotherapy for early-stage breast cancer is uncertain and not commonly used. The role of gene recurrence scores like oncotype Dx and mammaprint is evolving and can be used as an aid for adjuvant chemotherapy. Majority of metastatic MBC are treated with hormonal therapy with either tamoxifen, gonadotropin-releasing hormone agonist (GnRH) with aromatase inhibitors (AI), or fulvestrant. Chemotherapy is reserved for patients with visceral crisis or rapidly growing tumors.

Prolonged benefit from palbociclib plus letrozole in heavily pretreated advanced male breast cancer: case report

INTRODUCTION

Breast cancer in men is less common than in women and treatment recommendations are often derived from clinical trials exclusively involving women. Data on efficacy of CDK 4/6 inhibitors, which are the mainstay of treatment for hormone receptor-positive/HER2-negative advanced breast cancer, are lacking in male patients.

CASE REPORT

We present a clinical case of prolonged benefit from palbociclib in combination with letrozole and LHRH analogue in a man who had previously been treated with six lines of endocrine therapies and chemotherapy regimens but was still in excellent clinical condition.

CONCLUSIONS

This clinical case demonstrates that male breast cancer stands out as an endocrine-sensitive disease, which could potentially benefit from CDK 4/6 inhibitors in combination with endocrine agents even in very heavily pretreated settings of disease, underscoring both the importance of an accurate selection of patients for later treatment lines, taking into account disease history and previous treatment responses, and the peculiarity of breast cancer in men, which deserves dedicated clinical trials to tailor future recommendations.

Pseudoachalasia: a systematic review of the literature

Pseudoachalasia, also known as secondary achalasia, is a clinical condition mimicking idiopathic achalasia but most commonly caused by malignant tumors of gastroesophageal junction (GEJ). Our aim was to systematically review and present all available data on demographics, clinical features, and diagnostic modalities involved in patients with pseudoachalasia. A systematic search of literature published during the period 1978-2019 was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (end-of-search date: June 25th, 2019). Two independent reviewers extracted data with regards of study design, interventions, participants, and outcomes. Thirty-five studies met our inclusion criteria and were selected in the present review. Overall, 140 patients with pseudoachalasia were identified, of whom 83 were males. Mean patient age was 60.13 years and the mean weight loss was 13.91 kg. A total of 33 (23.6%) patients were wrongly 'treated' at first for achalasia. The most common presenting symptoms were dysphagia, food regurgitation, and weight loss. The median time from symptoms' onset to hospital admission was 5 months. Most common etiology was gastric cancer (19%). Diagnostic modalities included manometry, barium esophagram, endoscopy, and computed tomography (CT). Pseudoachalasia is a serious medical condition that is difficult to be distinguished from primary achalasia. Clinical feature assessment along with the correct interpretation of diagnostic tests is nowadays essential steps to differentiate pseudoachalasia from idiopathic achalasia.

Pharmacological management of male breast cancer

INTRODUCTION

Despite its rarity, male breast cancer shows a steadily rising incidence. Given the absence of ad hoc prospective randomized clinical trials, treatment strategies are based on extrapolation from female breast cancer recommendations or solely on population-based data.

AREAS COVERED

This review discusses the current treatment landscape for male breast cancer in the adjuvant and in the metastatic setting. The authors also discuss the biology and genomic landscape of male breast cancer. Original research and review articles, relative to the period 2010-2019, were included in the review of the literature.

EXPERT OPINION

There is a major medical need to include male patients with breast cancer in prospective clinical trials. The call to equality in breast cancer care can be pursued via two divergent paths: (i) a gender-neutral delivery of breast cancer information and (ii) the creation of separate sections, for the more common female breast cancer and for the rare male ones. We propose to differentiate male breast cancer care, acknowledging unique onco-sexual and social needs that can be only partially shared.

Management of Male Breast Cancer: ASCO Guideline

PURPOSE

To develop recommendations concerning the management of male breast cancer.

METHODS

ASCO convened an Expert Panel to develop recommendations based on a systematic review and a formal consensus process.

RESULTS

Twenty-six descriptive reports or observational studies met eligibility criteria and formed the evidentiary basis for the recommendations.

RECOMMENDATIONS

Many of the management approaches used for men with breast cancer are like those used for women. Men with hormone receptor-positive breast cancer who are candidates for adjuvant endocrine therapy should be offered tamoxifen for an initial duration of five years; those with a contraindication to tamoxifen may be offered a gonadotropin-releasing hormone agonist/antagonist plus aromatase inhibitor. Men who have completed five years of tamoxifen, have tolerated therapy, and still have a high risk of recurrence may be offered an additional five years of therapy. Men with early-stage disease should not be treated with bone-modifying agents to prevent recurrence, but could still receive these agents to prevent or treat osteoporosis. Men with advanced or metastatic disease should be offered endocrine therapy as first-line therapy, except in cases of visceral crisis or rapidly progressive disease. Targeted systemic therapy may be used to treat advanced or metastatic cancer using the same indications and combinations offered to women. Ipsilateral annual mammogram should be offered to men with a history of breast cancer treated with lumpectomy regardless of genetic predisposition; contralateral annual mammogram may be offered to men with a history of breast cancer and a genetic predisposing mutation. Breast magnetic resonance imaging is not recommended routinely. Genetic counseling and germline genetic testing of cancer predisposition genes should be offered to all men with breast cancer.

Male patient with metastatic stage IV breast cancer achieves complete remission on second line Abemaciclib, Fulvestrant and Leuprolide: A case report

Male breast cancer occurs rarely, comprising <1% of breast cancers. Due to the low incidence of male breast cancer, clinical trials of this disease are lacking. Therefore, therapeutic strategies utilized in the management of female breast cancer are often applied to male patients with breast cancer. Specifically, clinical outcomes using CDK 4/6 inhibitors require further investigation in male patients. To the best of our knowledge, the present report presents the first known case of a male patient treated with second line Abemaciclib, Lupron and Fulvestrant, producing complete remission. To the best of our knowledge this is also the first report of complete remission in a male breast cancer patient with a regimen utilizing a CDK 4/6 inhibitor.

A contemporary review of male breast cancer: current evidence and unanswered questions

Male breast cancer is rare, accounting for 1% of all breast cancer diagnoses in the USA. Because of its rarity, most major breast cancer trials have included only female patients. This has resulted in limited prospective data to guide the clinical management of men with breast cancer. As a result, treatment decisions are typically extrapolated from data generated in female patients. This approach may be suboptimal, particularly considering the differing hormonal milieus between men and women with respect to both breast cancer development and treatment. Herein, we summarize current knowledge of the biology and clinicopathology of male breast cancer and review current approaches to locoregional and systemic management of this rare disease.

Clinical utility of fulvestrant in the treatment of breast cancer: a report on the emerging clinical evidence

Fulvestrant is the first selective estrogen receptor (ER) downregulator available in clinical practice. It is a pure antiestrogen with no agonistic effects, leading to degradation of ER alpha, with activity in tamoxifen-resistant breast cancer (BC) models. Pharmacokinetic and pharmacodynamic studies and several postmarketing clinical trials led to the definition of the optimal dose at 500 mg intramuscularly on days 1, 15, and 29 and then every 28 days. Targeting ER alpha, fulvestrant is a cornerstone of treatment in luminal BCs, whose growth is largely driven by the ER pathway. In endocrine therapy-naïve patients with hormone receptor-positive, HER2− advanced BC (ABC), fulvestrant yielded significantly longer progression-free survival compared to anastrozole in the Phase III FALCON study. Due to its mechanism of action and pharmacokinetic properties, fulvestrant is an ideal backbone for combination therapies. Preclinical studies have shown synergism with drugs acting on signaling pathways involved in the development of endocrine resistance, among which the cyclin D/cyclin-dependent kinase 4-6/retinoblastoma pathway and the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin pathway, contributing to overcoming or delaying endocrine resistance. In the Phase III PALOMA-3 trial, a combination of the cyclin-dependent kinase 4/6 inhibitor palbociclib with fulvestrant significantly improved progression-free survival over fulvestrant alone in women with hormone receptor positive, HER2− ABC progressing during prior endocrine therapy. This led to approval of the combination in this clinical setting. Similar results were obtained with abemaciclib and ribociclib. Combination with pan-PI3K inhibitors, though showing some efficacy, was hampered by the toxicity of these agents, and studies in combinations with more selective inhibitors of the α-catalytic subunit of PI3K are ongoing. Fulvestrant has shown partial activity also in patients with tumors harboring mutations of the ESR1 gene. It is thus a key drug in the treatment of ABC, whose role in combination with new targeted agents is still evolving.

Squamous cell carcinoma of the pancreas: A systematic review and pooled survival analysis

The diagnosis and treatment of squamous cell carcinoma of the pancreas pose dilemmas in the clinical practice. The present study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eligible articles were sought in MEDLINE up to 30th April 2016. A pooled Cox regression analysis was performed to evaluate factors potentially associated with overall survival (OS) and relapse-free survival (RFS). Fifty-four cases of pure squamous cell pancreatic carcinomas were identified in total. The mean age was 61.9 years, and most patients were males (61.1%). The median OS was 7 months. Resectability (p = 0.003) and more recent publication year (p < 0.001) were associated with better OS, as was low/intermediate tumour grade (p = 0.032) with RFS. Despite its poor prognosis, survival rates of pancreatic squamous cell carcinoma seem improved during the recent years; resectability and low/intermediate grade emerged as favourable prognostic factors. Collaborative epidemiological studies are deemed necessary to further validate the results stemming from the published case reports of this rare entity.

Special considerations in the evaluation and management of breast cancer in men

Breast cancer in men is relatively uncommon but its incidence has been rising. Traditionally, the management of breast cancer in men is based on extrapolation from clinical trials of breast cancer in women, due to the much more extensive data available in women with this disease. There are, however, unique characteristics that distinguish breast cancer in men and these should be taken into consideration when managing this patient population. Breast cancer in men is more frequently estrogen receptor (ER) and progesterone receptor (PgR) positive, and less frequently HER2 amplified. Lobular carcinoma, which accounts for 10-15% of breast cancers in women, is exceptionally rare in men. Genetic risk factors, particularly BRCA2 mutations, are increasingly recognized as a key risk factor for breast cancer in men and genetic testing is now routinely recommended for all men diagnosed with breast cancer. Tamoxifen remains the gold standard endocrine therapy for breast cancer in men, but other endocrine agents such as the aromatase inhibitors (AI) and fulvestrant are increasingly being used. While superior to tamoxifen in postmenopausal women, the use of AIs for adjuvant therapy in men with breast cancer may not be optimal since the physiology of hormonal regulation in men resembles that of premenopausal rather than postmenopausal women. Emerging areas of investigation include the role of genomic risk stratification to gain further insight into the biology of breast cancer in men, the study of the androgen receptor (AR) as a therapeutic target, and the role of gonadal suppression in the management of the disease. There is clearly a more consorted effort to study breast cancer in men as a unique disease in order to have a better understanding of its biology and we are likely to witness further advances that will help us better manage this unique disease situation.

Obesity and male breast cancer: provocative parallels?

While rare compared to female breast cancer the incidence of male breast cancer (MBC) has increased in the last few decades. Without comprehensive epidemiological studies, the explanation for the increased incidence of MBC can only be speculated. Nevertheless, one of the most worrying global public health issues is the exponential rise in the number of overweight and obese people, especially in the developed world. Although obesity is not considered an established risk factor for MBC, studies have shown increased incidence among obese individuals. With this observation in mind, this article highlights the correlation between the increased incidence of MBC and the current trends in obesity as a growing problem in the 21(st) century, including how this may impact treatment. With MBC becoming more prominent we put forward the notion that, not only is obesity a risk factor for MBC, but that increasing obesity trends are a contributing factor to its increased incidence.

Role of gonadotropin-releasing hormone analogues in metastatic male breast cancer: results from a pooled analysis

Background

Male breast cancer is a rare malignancy. Despite the lack of prospectively generated data from trials in either the adjuvant or metastatic setting, patients are commonly treated with hormone therapies. Much controversy exists over the use of gonadotropin-releasing hormone analogues in metastatic male breast cancer patients. We conducted this study to provide more concrete ground on the use of gonadotropin-releasing hormone analogues in this setting.

Methods

We herein present results from a pooled analysis including 60 metastatic male breast cancer patients treated with either an aromatase inhibitor or cyproterone acetate as a monotherapy (23 patients) or combined with a gonadotropin-releasing hormone analogue (37 patients).

Results

Overall response rate was 43.5 % in patients treated with monotherapy and 51.3 % with combination therapy (p = 0.6). Survival outcomes favored combination therapy in terms of median progression-free survival (11.6 months versus 6 months; p = 0.05), 1-year progression-free survival rate (43.2 % versus 21.7 %; p = 0.05), median overall survival (29.7 months versus 22 months; p = 0.05), and 2-year survival rate (64.9 % versus 43.5 %; p = 0.05).

Conclusions

In metastatic male breast cancer patients, the combined use of gonadotropin-releasing hormone analogues and aromatase inhibitors or antiandrogens seems to be associated with greater efficacy, particularly in terms of survival outcomes, compared with monotherapy. Collectively, these results encourage considering these agents in the metastatic setting.

Efficacy of chemotherapy in metastatic male breast cancer patients: a retrospective study

Background

The role of chemotherapy in the treatment of metastatic male breast cancer patients remains unknown, and the only available evidence stem from small, retrospective series evaluating outdated drugs and/or regimens.

Methods

In this retrospective study we evaluated the activity of polychemotherapy, consisting of three-drug (anthracycline-containing and anthracycline-free) regimens, as a first-line therapy for metastatic male breast cancer patients who had received at least one prior endocrine therapy.

Results

Fifty patients treated between 1978 and 2013 were included in the present analysis. Regarding best response, we recorded 1 (2%) complete response and 27 (54%) partial responses, for an overall response rate of 56% (95% CI, 42.2-69.8). Considering stable disease, the disease control rate was 84%. Median progression-free survival was 7.2 months (95% CI, 5.9-8.5), and median overall survival was 14.2 months (95% CI, 12.2-16.2). Albeit we observed some differences for all the outcomes explored when comparing anthracycline-containing and anthracycline-free regimens, they were not statistically significant.

Conclusions

Chemotherapy, consisting in both anthracycline-containing and anthracycline-free regimens, showed encouraging antitumor activity in metastatic male breast cancer patients previously treated with endocrine therapy.