Angiogenesis, p53, and c-erbB-2 immunoreactivity and clinicopathological features in male breast cancer

Defining genomic, transcriptomic, proteomic, epigenetic, and phenotypic biomarkers with prognostic capability in male breast cancer: a systematic review

Although similar phenotypically, there is evidence that male and female breast cancer differ in their molecular landscapes. In this systematic review, we consolidated all existing prognostic biomarker data in male breast cancer spanning genetics, transcriptomics, proteomics, and epigenetics, and phenotypic features of prognostic value from articles published over a 29-year period (March 16, 1992, to May 1, 2021). We identified knowledge gaps in the existing literature, discussed limitations of the included studies, and outlined potential approaches for translational biomarker discovery and validation in male breast cancer. We also recognised STC2, DDX3, and DACH1 as underexploited markers of male-specific prognostic value in breast cancer. Finally, beyond describing the cumulative knowledge on the extensively researched markers oestrogen receptor-α, progesterone receptor, HER2, androgen receptor, and BRCA2, we highlighted ATM, CCND1, FGFR2, GATA3, HIF1-α, MDM2, TP53, and c-Myc as well studied predictors of poor survival that also aligned with several hallmarks of cancer.

An update on male breast cancer and future directions for research and treatment

Male breast cancer is a rare disease for which treatment has been based on the evidence available from female breast cancer. The new genomic tools can better characterize the biology of breast cancer. It is hoping that these will help to clarify possible differences of breast cancer behaviour in male patients, which will have a major impact on treatment strategies and on the conduct of clinical trials in this setting. In this review we will summarize available information on epidemiology, risk factors for breast cancer in men, the new insights of the biology of this disease, current recommendations for treatment and insights for future research.

Male breast cancer: risk factors, biology, diagnosis, treatment, and survivorship

BACKGROUND

The causes, optimal treatments, and medical/psychosocial sequelae of breast cancer in men are poorly understood.

DESIGN

A systematic review of the English language literature was conducted to identify studies relevant to male breast cancer between 1987 and 2012 and including at least 20 patients. Searches were carried out on PubMed using the title terms 'male breast cancer' or 'male breast carcinoma'.

RESULTS

Relevant published data regarding risk factors, biological characteristics, presentation and prognosis, appropriate evaluation and treatment, and survivorship issues in male breast cancer patients are presented. BRCA2 mutations, age, conditions that alter the estrogen/androgen ratio, and radiation are proven risk factors. Disease biology is distinct in men, but diagnostic approaches and treatments for men are generally extrapolated from those in women due to inadequate research in men. Survivorship issues in men may include sexual and hormonal side-effects of endocrine therapies as well as unique psychosocial impacts of the disease.

CONCLUSION

Further research is needed to address gaps in knowledge pertaining to care of male breast cancer patients and survivors.

A comparative biomarker study of 514 matched cases of male and female breast cancer reveals gender-specific biological differences

Male breast cancer remains understudied despite evidence of rising incidence. Using a co-ordinated multi-centre approach, we present the first large scale biomarker study to define and compare hormone receptor profiles and survival between male and female invasive breast cancer. We defined and compared hormone receptor profiles and survival between 251 male and 263 female breast cancers matched for grade, age, and lymph node status. Tissue microarrays were immunostained for ERα, ERβ1, -2, -5, PR, PRA, PRB and AR, augmented by HER2, CK5/6, 14, 18 and 19 to assist typing. Hierarchical clustering determined differential nature of influences between genders. Luminal A was the most common phenotype in both sexes. Luminal B and HER2 were not seen in males. Basal phenotype was infrequent in both. No differences in overall survival at 5 or 10 years were observed between genders. Notably, AR-positive luminal A male breast cancer had improved overall survival over female breast cancer at 5 (P = 0.01, HR = 0.39, 95% CI = 0.26-0.87) but not 10 years (P = 0.29, HR = 0.75, 95% CI = 0.46-1.26) and both 5 (P = 0.04, HR = 0.37, 95% CI = 0.07-0.97) and 10 years (P = 0.04, HR = 0.43, 95% CI = 0.12-0.97) in the unselected group. Hierarchical clustering revealed common clusters between genders including total PR-PRA-PRB and ERβ1/2 clusters. A striking feature was the occurrence of ERα on distinct clusters between genders. In female breast cancer, ERα clustered with PR and its isoforms; in male breast cancer, ERα clustered with ERβ isoforms and AR. Our data supports the hypothesis that breast cancer is biologically different in males and females suggesting implications for clinical management. With the incidence of male breast cancer increasing this provides impetus for further study.

Clinicopathologic and immunohistochemical characteristics of male breast cancer: a single center experience

Male breast cancer (MaleBC) is a rare tumor that has been insufficiently described in the Middle East. The purpose of this study is to report the first MaleBC series in Lebanon, describing its clinicopathologic and immunohistochemical phenotype, and how it compares with MaleBC in the West and with female breast cancer in Lebanon and the Middle East. Forty-seven cases of MaleBC were reviewed. Results showed younger ages at presentation (62 years versus 67 years), higher incidence of lobular carcinoma (6% versus 1%), and more frequent p53 positivity and axillary node metastases in our series than in those reported about MaleBC. Other results such as higher estrogen receptor (ER) positivity and lower HER-2/neu over-expression were comparable to the literature. These findings suggest that MaleBC in our region may represent a biologically different tumor with potentially distinct prognostic and therapeutic implications.

Male breast cancer

Male breast cancer (MBC) is a rare disease. However, as global populace ages, there is a trend to MBC increasing. Although aetiology is still unclear, constitutional, environmental, hormonal (abnormalities in estrogen/androgen balance) and genetic (positive family history, Klinefelter syndrome, mutations in BRCA1 and specially BRCA2) risk factors are already known. Clinic manifestation is painless hard and fixed nodule in the subareolar region in 75% of cases, with nipple commitment earlier than in women. Breast cancer has similar prognostic factors in males and females, among which axillary adenopathy (present in 40-55% cases) is the most important one. Although mammography, ultrasonography and scintigraphy can be useful tools in diagnosis; clinical assessment, along with a confirmatory biopsy, remains the main step in the evaluation of men with breast lesions. Infiltrating ductal carcinoma is the most frequent histological type. The established standard of care is modified radical mastectomy followed by tamoxifen for endocrine-responsive positive disease, although other options are being explored. While similarities between breast cancer in males and females exist, it is not appropriate to extrapolate data from female disease to the treatment of male. There is a need for specific multi-institutional trials to better understanding of clinicopathologic features and establishment of optimal therapy for this disease.

Pharmacologic treatment of male breast cancer

Male breast cancer is an uncommon condition. It often occurs in settings in which there is an imbalance between androgens and oestrogens. Genetics plays an important role, as many cases are associated with mutations in BRCA2 or other genes. Male breast cancer occurs at an older age than female breast cancer and is frequently diagnosed at a later stage. Tumors are predominantly oestrogen and progesterone positive. Prognosis is approximately equivalent to that of breast cancer in females when matched for age, stage and hormonal receptors. The recommended treatment for male breast cancer is similar to that for breast cancer in postmenopausal females. However, the presence of androgens in males has a strong effect on the hormonal milieu and the ability of male patients to respond to hormonal agents. When pharmacologic treatment is required, tamoxifen is effective for first-line therapy. Other hormonal approaches such as orchiectomy, aromatase inhibitors and androgen ablation may be useful in later lines of therapy.

Male breast cancer: is the scenario changing

Background

The overall incidence of male breast cancer is around 1% of all breast cancers and is on the rise. In this review we aim to present various aspects of male breast cancer with particular emphasis on incidence, risk factors, patho-physiology, treatment, prognostic factors, and outcome.

Methods

Information on all aspects of male breast cancer was gathered from available relevant literature on male breast cancer from the MEDLINE database over the past 32 years from 1975 to 2007. Various reported studies were scrutinized for emerging evidence. Incidence data were also obtained from the IARC, Cancer Mondial database.

Conclusion

There is a scenario of rising incidence, particularly in urban US, Canada and UK. Even though more data on risk factors is emerging about this disease, more multi-institutional efforts to pool data with large randomized trials to show treatment and survival benefits are needed to support the existing vast emerging knowledge about the disease.

The status and role of ErbB receptors in human cancer

Changes in the expression of cellular receptors contribute to the progression of many types of solid tumors. In this review, we focus on the normal role of ErbB receptors as signal transducers and their contribution to carcinogenesis when there are abnormalities in ErbB signaling due to the overactivity of the receptors or the overexpression of ligands, which can lead to developmental defects and have been associated with many types of cancers.

Male breast cancer: a gender issue

The incidence of male breast cancer (MBC) is rising; however, mortality due to MBC has not changed, unlike female breast cancer. This lack of change is mostly attributable to a lack of major progress in the understanding and treatment of the disease. The treatment of MBC has been extrapolated from the knowledge of female breast cancer, despite the multiple differences in the pathogenesis, biology and genetics of these two disease entities, especially the differences with regard to the role of male hormones as well as estrogens in MBC compared with female disease. Although major advances in hormonal manipulation for the treatment of breast cancer are being developed, an improved understanding of the potential differences between male and female breast cancer is essential, as this would provide new opportunities for therapeutic intervention and probable improved outcome for MBC. This review aims at highlighting the major differences between male and female breast cancer with an emphasis on hormonal therapy, and discusses some of the recent advances in MBC.

Angiogenesis in male breast cancer

Background

Male breast cancer is a rare but aggressive and devastating disease. This disease presents at a later stage and in a more advanced fashion than its female counterpart. The immunophenotype also appears to be distinct when compared to female breast cancer. Angiogenesis plays a permissive role in the development of a solid tumor and provides an avenue for nutrient exchange and waste removal. Recent scrutiny of angiogenesis in female breast cancer has shown it to be of significant prognostic value. It was hypothesized that this holds true in invasive ductal carcinoma of the male breast. In the context of male breast cancer, we investigated the relationship of survival and other clinico-pathological variables to the microvascular density of the tumor tissue.

Methods

Seventy-five cases of primary male breast cancer were identified using the records of the Saskatchewan Cancer Agency over a period of 26 years. Forty-seven cases of invasive ductal carcinoma of the male breast had formalin-fixed paraffin-embedded tissue blocks that were suitable for this study. All cases were reviewed. Immunohistochemical staining was performed for the angiogenic markers (cluster designations 31 (CD31), 34 (CD34) and 105 (CD105), von Willebrand factor (VWF), and vascular endothelial growth factor (VEGF)). Microvascular density (MVD) was determined using average, centre, and highest microvessel counts (AMC, CMC, and HMC, respectively). Statistical analyses compared differences in the distribution of survival times and times to relapse between levels of MVD, tumor size, node status and age at diagnosis. In addition, MVD values were compared within each marker, between each marker, and were also compared to clinico-pathological data.

Results

Advanced age and tumor size were related to shorter survival times. There were no statistically significant differences in distributions of survival times and times to relapse between levels of MVD variables. There was no significant difference in MVD between levels of the different clinico-pathological variables. MVD was strongly and significantly correlated between AMC, CMC and HMC for CD31, CD34, and CD105 (p < 0.01) and remained moderate to weak for VWF and VEGF.

Conclusion

Microvascular density does not appear to be an independent prognostic factor in male breast cancer. However, the likelihood of death for men with breast cancer is increased in the presence of increased age at diagnosis and advanced tumor size. This is perhaps linked to inherent tumor vasculature, which is strongly related throughout a tumor section.

Targeted therapy in breast cancer: the HER-2/neu gene and protein

The HER-2/neu oncogene, a member of the epidermal growth factor receptor or erb gene family, encodes a transmembrane tyrosine kinase receptor that has been linked to prognosis and response to therapy with the anti-HER-2-humanized monoclonal antibody, trastuzumab (Herceptin, Genentech, South San Francisco, CA) in patients with advanced metastatic breast cancer. HER-2/neu status has also been tested for its ability to predict the response of breast cancer to other therapies including hormonal therapies, topoisomerase inhibitors, and anthracyclines. This review includes an analysis of 80 published studies encompassing more than 25,000 patients designed to consider the relative advantages and disadvantages of the various methods of measuring HER-2/neu in clinical breast cancer specimens. Southern blotting, PCR amplification detection, and fluorescence in situ hybridization assays designed to detect HER-2/neu gene amplification are compared with HER-2/neu protein overexpression assays performed by immunohistochemical techniques applied to frozen and paraffin-embedded tissues and enzyme immunoassays performed on tumor cytosols. The significance of HER-2/neu overexpression in ductal carcinoma in situ and the HER-2/neu status in uncommon female breast conditions and male breast cancer are also considered. The role of HER-2/neu testing for the prediction of response to trastuzumab therapy in breast cancer is reviewed along with the current studies designed to test whether HER-2/neu status can predict the response to standard and newer hormonal therapies, cytotoxic chemotherapy, and radiation. The review will also evaluate the status of serum-based testing for circulating HER-2/neu receptor protein and its ability to predict disease outcome and therapy response.

The Her-2/neu gene and protein in breast cancer 2003: biomarker and target of therapy

The HER-2/neu oncogene encodes a transmembrane tyrosine kinase receptor with extensive homology to the epidermal growth factor receptor. In this review, the association of HER-2/neu gene and protein abnormalities with prognosis and response to therapy with trastuzumab and to other therapies in breast cancer is presented. By considering a series of 80 published studies encompassing more than 25,000 patients, the relative advantages and disadvantages of Southern blotting, polymerase chain reaction amplification, and fluorescence in situ hybridization assays designed to detect HER-2/neu gene amplification are compared with HER-2/neu protein overexpression assays performed by immunohistochemical techniques applied to frozen and paraffin-embedded tissues and enzyme immunoassays performed on tumor cytosols. The significance of HER-2/neu overexpression in ductal carcinoma in situ and the HER-2/neu status in uncommon female breast conditions and male breast cancer are also considered. The role of HER-2/neu testing for the prediction of response to trastuzumab therapy in breast cancer is presented as well as its potential impact on responses to standard and newer hormonal therapies, cytotoxic chemotherapy, and radiation. The review also evaluates the status of serum-based testing for circulating HER-2/neu receptor protein and its ability to predict disease outcome and therapy response.

Male versus female breast cancers. A population-based comparative immunohistochemical analysis

CONTEXT

The rate of male breast cancer is a small fraction of that observed in females, thus severely limiting our understanding of the pathogenesis of this condition. It remains unclear whether the biological behavior and tumor progression associated with male breast cancer parallel that of the female form.

OBJECTIVES

To evaluate the immunohistochemical profile of male breast carcinomas and to compare this profile with that of stage-matched female breast cancers.

DESIGN

Seventy-five cases of primary male breast cancer were identified using the records of the Saskatchewan Cancer Foundation over a period of 26 years (1970-1996). Fifty-nine of these cases had formalin-fixed, paraffin-embedded tissue blocks available for the purposes of this study. All cases were reviewed and a standardized modified Bloom-Richardson grading criterion was applied. Estrogen receptor status, progesterone receptor status, c-Erb-B2 expression, p53 expression, and Bcl-2 expression were evaluated by immunohistochemistry. Results from 240 consecutive cases of stage-matched female breast cancers analyzed in the same laboratory were used as a standard set for comparison.

RESULTS

Male breast cancers tended to be high grade (85% grade 3) in comparison with the female breast cancers (50% grade 3). In descriptive analysis across all stages of disease, male carcinomas were more frequently estrogen receptor positive (81% vs 69%) than their female counterparts. Despite their high grade, they were less likely to overexpress p53 (9% vs 28%) and Erb-B2 (5% vs 17%) than the female counterparts. There was no significant difference in either progesterone receptor (63% vs 56%) or Bcl-2 (79% vs 76%) overexpression. Stratified analysis by stage-matched controls showed no statistically significant differences among the men and women with stage I disease. However, in stage II-matched samples, statistically significant differences were observed between the 2 groups. The male cancers were more likely to overexpress estrogen receptor (81.6% vs 64.4%, P = .04), progesterone receptor (71.1% vs 47.5%, P = .01), and Bcl-2 (78.9% vs 69.4%, P = .20). They also showed statistically significant lower expression of p53 (7.9% vs 36.3%, P = .001) and Erb-B2 (5.3% vs 23.8% P = .01).

CONCLUSION

Male breast cancers display distinct immunophenotypic differences from those occurring in women, implying a different pathogenesis in the evolution and progression of this disease. Such differences may play key roles in therapeutic management, warranting different treatment strategies in comparison to female breast cancers.

Androgen-dependent mammary carcinogenesis in rats transgenic for the Neu proto-oncogene

Transgenic rats were created with overexpression of the Neu proto-oncogene in the mammary gland of both sexes, yet only males developed mammary cancer in an androgen-dependent fashion. Transgenic females only developed mammary cancer if treated with androgens. These tumors were positive for androgen receptor (AR), but negative for estrogen and progesterone receptors. Extensive analysis failed to detect mutations anywhere within the neu transgene from mammary carcinomas. Established mammary carcinomas eventually escaped their dependency on androgens. Transgenic long-term gonadectomized rats did not develop mammary cancer, but Neu overexpression stimulated the growth of their mammary glands. Our results suggest crosstalk between the Neu proto-oncogene and AR signaling pathways in the growth of both the normal and cancerous mammary epithelium.

Pharmacotherapy for male breast cancer

Breast cancer in males is uncommon, occurring at approxiamtely 1% of the rate of female breast cancer. Male breast carcinomas tend to be highly positive for hormone receptors, including oestrogen, progesterone and androgen receptors. Owing to this, hormone therapy is recommended as the primary treatment modality. Adjuvant therapy is recommended for male breast cancers with large size or positive axillary nodes. For metastatic disease, options for therapy include tamoxifen, orchiectomy, anti-androgens with or without luteinising hormone releasing hormone analogues or combination chemotherapy. The newer hormonal treatments, such as the selective aromatase inhibitors or novel antioestrogens, have not yet been well studied in male breast cancer but have potential for efficacy in this disease.

Clinical management of breast cancer in males: a report of four cases

Breast cancer in men is a rare cancer manifestation, accounting for less then 1% of all breast cancers in both genders. The incidence in Germany during the last years has been approximately 1.0 per year/100,000. In the US, only 0.2% of all malignancies in men. Predisposing risk factors seem to include radiation exposure, hereditary factors, estrogen administration, and diseases associated with hyperestrogenism, such as cirrhosis of the liver or genetic syndromes (i.e. Klinefelter disease). The incidence of male breast cancer is increased in families with a number of first degree relatives affected with breast or prostate cancer. An increased risk of male breast cancer has been reported in families with a mutation of the breast cancer susceptibility gene BRCA-2. For a period of decades, prognosis of breast cancer in males was thought to be worse than that of female patients. Data and cases being published demonstrate that prognosis and strategies of treatment in male breast cancer do not differ from those in females. The cases presented clearly demonstrate that diagnostic work-up, staging procedures and treatment options for primary treatment and advanced stages are identical compared to the recommendation for female breast cancer.

Expression of c-erbB-2, p53 and c-myc proteins in male breast carcinoma: Comparison with traditional prognostic factors and survival

There are few data evaluating biological markers for men with breast cancer. The purpose of the present study was to analyze the expression of the oncogenes c-erbB-2 and c-myc and of the suppressor gene p53 by immunohistochemical techniques in archival paraffin-embedded tissue blocks of 48 male breast cancer patients, treated at the A.C. Camargo Cancer Hospital, São Paulo, SP, Brazil. The results were compared with clinicopathological prognostic features. Immunopositivity of c-erbB-2, p53 and c-myc was detected in 62.5, 16.7 and 20.8% of the cases analyzed, respectively. Estrogen and progesterone receptors were positive in 75 and 69% of the cases, respectively. Increasing staging was statistically associated with c-erbB-2 (P = 0.04) and weakly related to p53 positivity (P = 0.06). No significant correlation between specific survival rate (determined by the log rank test) and the molecular markers analyzed was found, whereas the number of compromised lymph nodes and advanced TNM (tumor, node, metastasis) staging were associated with diminished survival.