Androgen receptor expression in male breast carcinoma: lack of clinicopathological association

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.

Gender Disparity in Breast Cancer: A Veteran Population-Based Comparison

BACKGROUND

Male breast cancer (MBC) comprises <1% of all cancers and continues to rise. Because of rarity, there is paucity in the literature; therefore, management of MBC is generalized from female breast cancer (FBC).

METHODS

Data from 152 VA Medical Centers were used to analyze the database of Veteran patient with breast cancer diagnosed between 1998 and 2016 using biostatistical software (SAS 9.3). Our primary objective is to compare patient's demographics, breast cancer characteristics, and outcomes for male and female Veterans.

FINDING

In total, 8864 patients' records were reviewed;1528 MBC were compared with 7336 FBC with a mean follow up time of 5.5 years (SD 4.17). The mean age at diagnosis was 68.6 years and 57.3 years for MBC and FBC, respectively (P < .0001). Higher numbers of MBC patients (95%) were >50 years of age compared to FBC patients (72%). More MBC patients (16.8 vs. 9.1% and 9 vs. 4%) presented with higher disease stage (III and IV, respectively). Estrogen receptor-positive tumors were more common in MBC (59 versus 52%). Hormonal treatment was received by 27% of MBC versus 19% FBC; chemotherapy 21.3% versus 41.5% and radiation 23.5% versus 60.9%. Forty-two percent MBC and 20% FBC Veterans died during study. Male patients had higher death rate 1.285 (95% CI: 1.150, 1.434, P < .0001) compared to females after adjusting data for age, race, stage, and grade.

INTERPRETATION

To the best of our knowledge, this is the largest comparison series of MBC and FBC to date in the Veterans population. The higher mortality rate in MBC patients may be due to late presentation, higher stage at the time of diagnosis and/or tumor biology. Veteran's exposures to hazardous materials during their military deployments as an additional factor for worse prognosis need further investigation.

Androgen receptor: A promising therapeutic target in breast cancer

Breast cancer (BCa) is the second most common cancer worldwide and the most prevalent cancer in women. The majority of BCa cases are positive (+) for the estrogen receptor (ER⁺, 80%) and progesterone receptor (PR⁺, 65%). Estrogen and progesterone hormones are known to be involved in cancer progression, and thus hormonal deprivation is used as an effective treatment for ER⁺PR⁺ BCa subtypes. However, some ER⁺PR⁺ BCa patients develop resistance to such therapies. Meanwhile, chemotherapy is the only available treatment for ER^-PR^- BCa tumors. Another hormone receptor known as the androgen receptor (AR) has also been found to be widely expressed in human breast carcinomas. However, the mechanisms of AR and its endogenous androgen ligands is not well-understood in BCa and its biological role in this hormone-related disease remains unclear. In this review, we aim to address the importance of the AR in BCa diagnosis and prognosis, current AR-targeting approaches in BCa, and the potential for AR-downstream molecules to serve as therapeutic targets.

Histological Grade in Breast Cancer: Association with Clinical and Biological Features in a Series of 229 Patients

In order to study the association of histological grade (HG) with specific clinical and biological parameters which may influence the clinical behavior of infiltrating ductal carcinomas of the breast (IDC), we analyzed in 229 tissue samples the cytosolic concentrations of estrogen receptor (ER), progesterone receptor (PR), pS2, cathepsin D, hyaluronic acid (HA) and tissue-type plasminogen activator (t-PA), as well as those of the erbB2 oncoprotein, epidermal growth factor receptor (EGFR), HA, CD44v5 and CD44v6 in the cell membrane fraction. Likewise, we considered size, ploidy, S-phase fraction and axillary node involvement as variables of the study. The transition from HG1 to HG2 and from HG2 to HG3 was accompanied by a number of common features: global increase in size, greater number of tumors >2.0 cm, decrease in membrane hyaluronic acid concentrations, increased cell proliferation (S-phase >7%) and greater aneuploidy. Other events observed during the transition from HG2 to HG3 were a decrease in ER, PR, t-PA and cytosolic hyaluronic acid. These results led us to consider that HG is associated with certain clinical-biological changes that may help explain its value as a prognostic factor in breast carcinomas.

Characterisation of male breast cancer: a descriptive biomarker study from a large patient series

Male breast cancer (MBC) is rare. We assembled 446 MBCs on tissue microarrays and assessed clinicopathological information, together with data from 15 published studies, totalling 1984 cases. By immunohistochemistry we investigated 14 biomarkers (ERα, ERβ1, ERβ2, ERβ5, PR, AR, Bcl-2, HER2, p53, E-cadherin, Ki67, survivin, prolactin, FOXA1) for survival impact. The main histological subtype in our cohort and combined analyses was ductal (81%, 83%), grade 2; (40%, 44%), respectively. Cases were predominantly ERα (84%, 82%) and PR positive (74%, 71%), respectively, with HER2 expression being infrequent (2%, 10%), respectively. In our cohort, advanced age (>67) was the strongest predictor of overall (OS) and disease free survival (DFS) (p = 0.00001; p = 0.01, respectively). Node positivity negatively impacted DFS (p = 0.04). FOXA1 p = 0.005) and AR p = 0.009) were both positively prognostic for DFS, remaining upon multivariate analysis. Network analysis showed ERα, AR and FOXA1 significantly correlated. In summary, the principle phenotype of MBC was luminal A, ductal, grade 2. In ERα+ MBC, only AR had prognostic significance, suggesting AR blockade could be employed therapeutically.

AR Signaling in Breast Cancer

Androgen receptor (AR, a member of the steroid hormone receptor family) status has become increasingly important as both a prognostic marker and potential therapeutic target in breast cancer. AR is expressed in up to 90% of estrogen receptor (ER) positive breast cancer, and to a lesser degree, human epidermal growth factor 2 (HER2) amplified tumors. In the former, AR signaling has been correlated with a better prognosis given its inhibitory activity in estrogen dependent disease, though conversely has also been shown to increase resistance to anti-estrogen therapies such as tamoxifen. AR blockade can mitigate this resistance, and thus serves as a potential target in ER-positive breast cancer. In HER2 amplified breast cancer, studies are somewhat conflicting, though most show either no effect or are associated with poorer survival. Much of the available data on AR signaling is in triple-negative breast cancer (TNBC), which is an aggressive disease with inferior outcomes comparative to other breast cancer subtypes. At present, there are no approved targeted therapies in TNBC, making study of the AR signaling pathway compelling. Gene expression profiling studies have also identified a luminal androgen receptor (LAR) subtype that is dependent on AR signaling in TNBC. Regardless, there seems to be an association between AR expression and improved outcomes in TNBC. Despite lower pathologic complete response (pCR) rates with neoadjuvant therapy, patients with AR-expressing TNBC have been shown to have a better prognosis than those that are AR-negative. Clinical studies targeting AR have shown somewhat promising results. In this paper we review the literature on the biology of AR in breast cancer and its prognostic and predictive roles. We also present our thoughts on therapeutic strategies.

A role for the androgen receptor in the treatment of male breast cancer

Male breast cancer (BC) is relatively rare, making up less than 1% of all breast cancer cases in the United States. Treatment guidelines for male BC are derived from studies on the treatment of female BC, and are based molecular and clinical characteristics, such as hormone receptor positivity. For female estrogen receptor positive (ER+) breast cancers, the standard of care includes three classes of endocrine therapies: selective estrogen receptor modulators, aromatase inhibitors, and pure anti-estrogens. In contrast to female ER+ breast cancers, there is less known about the optimal treatment for male ER+ BC. Furthermore, in contrast to ER, less is known about the role of the androgen receptor (AR) in male and female BC. We report here the treatment of a 28-year-old man with metastatic AR+, ER+ breast cancer otherwise refractory to chemotherapy, who has had a durable clinical response to hormonal suppression with the combination of aromatase inhibition (Letrozole) in conjunction with a GnRH agonist (Leuprolide).

Androgen receptor and antiandrogen therapy in male breast cancer

Cancers arising in the male breast are uncommon. Male breast cancer is a hormone-driven disease that often expresses the estrogen receptor, and antiestrogen therapy represents the mainstay of treatment. Paradoxically, the advent of a wave of antiestrogens eclipsed the therapeutic potential of alternative therapeutic options. At the beginning of the hormonal therapy era the administration of antiandrogens to metastatic male breast cancer patients was proposed. Ever since the use of these compounds has largely been neglected. A therapeutic role for antiandrogens has been envisioned again in recent years. First, molecular characterization efforts pointed to the androgen receptor as a potential therapeutic target. Second, the development of aromatase inhibitors unexpectedly raised the need for neutralizing androgens in order to tackle endocrine feedback mechanisms responsible for acquired resistance. We herein provide an overview of molecular studies where the androgen receptor was investigated at the genomic, transcriptomic or phenotypic level. We then discuss androgens in the context of the endocrine networks nourishing male breast cancer. Finally, clinical evidence on antiandrogens is summarized along with strategies should be implemented to improve the medical management of these patients.

Tracing differences between male and female breast cancer: both diseases own a different biology

AIMS

Male breast cancer (MBC) is a rare and poorly characterized disease. In the present study we used a novel biomathematical model to further characterize MBC and to identify differences between male and female breast cancer (FBC).

METHODS AND RESULTS

A total of 134 cases of MBC were stained immunohistochemically for 13 key oncoproteins, and staining percentages were used in a mathematical model to identify dependency patterns between these proteins. The results were compared with a large group of FBC (n = 728). MBC and FBC clearly differed on the molecular level. In detail, the results suggest a different role for progesterone receptor (PR) compared to oestrogen receptor (ER) in MBC, while in FBC ER and PR show a similar pattern. In addition, Androgen receptor (AR) seems to be a more powerful effector in MBC. Grades 1 and 2 tumours were clearly separated from grade 3 tumours, and luminal types A and B tumours also showed a different pattern.

CONCLUSIONS

Defined morphological and molecular phenotypes can be identified in MBC, but these seem to be the result of different molecular mechanisms and perhaps multiple genetic pathways, as characterized previously in FBC, emphasizing the rising concept that MBC and FBC should be regarded as different and unique diseases.

Androgen receptor expression in male breast cancer predicts inferior outcome and poor response to tamoxifen treatment

OBJECTIVE

Androgen receptor (AR) plays an important role in male breast cancer (MBC). Additionally, endocrine therapy is the most important treatment in oestrogen receptor (ER)-positive advanced breast cancer. This study was aimed to investigate the role of AR in MBC treatment and prognosis and to analyse the relationship between AR and the effect of tamoxifen treatment in MBC patients.

METHODS

AR protein levels and other tumour characteristics (e.g. expression of ER (ESR1), PR (PGR), AR, HER2 (ERBB2) and Ki-67 (MKI67)) in breast cancer tissue from 102 MBC patients were determined using immunohistochemical analysis. Additionally, the relationship between AR status and clinicopathological features was analysed using the χ(2)-test. Association with survival was initially analysed using the Kaplan-Meier method and the log-rank test, and Cox regression analysis was used to adjust for other prognostic indicators.

RESULTS

High expression of AR was not correlated with T-stage, histological grade, HER2 status and the status of other sex hormone receptors, but was associated with lymph node metastases (P=0.032). AR-positive patients showed significantly shorter 5-year overall survival (OS) rates (P=0.045) and 5-year disease-free survival (DFS) rates (P=0.026) than AR-negative patients. By contrast, for patients who received tamoxifen therapy, AR-negative patients showed a higher clinical benefit rate than AR-positive patients (P=0.025). Additionally, the median TTP and OS were significantly different (P=0.02 for TTP; P=0.029 for OS).

CONCLUSIONS

AR expression correlates strongly with both OS and DFS in patients with MBC. AR-positive patients can predict a poorer clinical outcome than AR-negative patients after adjuvant tamoxifen therapy.

Breast cancer: trends in international incidence in men and women

Background:

The age-standardised incidence of breast cancer varies geographically, with rates in the highest-risk countries more than five times those in the lowest-risk countries.

Methods:

We investigated the correlation between male (MBC) and female breast cancer (FBC) incidence stratified by female age-group (<50 years, and ⩾50 years) and used Poisson regression to examine male incidence rate ratios according to female incidence rates.

Results:

Age-adjusted breast cancer incidence rates for males and females share a similar geographic distribution (Spearman's correlation=0.51; P<0.0001). A correlation with male incidence rates was found for the entire female population and for women aged 50 years and over. Breast cancer incidence rates in males aged <50 years were not associated with FBC incidence, whereas those in males aged ⩾50 years were. MBC incidence displays a small ‘hook' similar to the Clemmesen's hook for FBC, but at a later age than the female hook.

Interpretation:

Further investigation of possible explanations for these patterns is warranted. Although the incidence of breast cancer is much lower in men than in women, it may be possible to identify a cause common to both men and women.

[Breast cancer in men: about 6 cases]

Le but de ce travail était d'analyser les caractéristiques cliniques, histologiques, thérapeutiques et pronostiques du cancer du sein chez l'homme. Il s'agissait d'une étude rétrospective portant sur six patients colligés au service de gynécologie obstétrique II, CHU Hassan II durant la période 2009-2012. L’âge moyen de nos patients est de 65.3 ans. Il s'agit dans 83.3% des cas, d'une tumeur rétroaréolaire dont la taille moyenne est de 44.16 mm. Nous avons retrouvé 4 (66.7%) T4, 1 (16.7%) T3 et dans un cas, une tumeur inclassable. Le type histologique le plus représenté est le carcinome canalaire infiltrant (66.7%). Le taux d'envahissement ganglionnaire axillaire est de 66.7%. L'hormonodépendance de ces tumeurs est prouvée dans 100% des cas. La survie à cinq ans est en cours d’évaluation. L'envahissement ganglionnaire, l'invasion du derme, le stade clinique TNM sont des facteurs qui influencent significativement la survenue de métastases. Aucun de ces facteurs de risque n'est apparu significatif en termes de survie globale. Le cancer du sein chez l'homme est une maladie rare (environ 1% des cancers du sein) au pronostic sombre. Le diagnostic est le plus souvent tardif et les lésions sont traitées à des stades avancés.

Poorer survival of male breast cancer compared with female breast cancer patients may be due to biological differences

OBJECTIVE

The objective of the study was to compare disease-free survival and overall survival in a group of matched males and females with breast cancer, and to analyze possible treatment- and gender-related differences.

METHODS

We retrospectively analyzed the data of 150 operable male breast cancer patients treated in our hospital from December 1980 to June 2012. Each male breast cancer patient recorded in the database was matched with two female breast cancer patients of equal stage. Prognosis in terms of disease-free survival and overall survival was evaluated.

RESULTS

The mean age at diagnosis was 58.6 ± 9.7 years for males and 57.2 ± 10.3 years for females. The median follow-up was 69 months for males and 81 months for females. Significant differences were identified for tumor location, hormone receptor status, molecular subtypes and hormone therapy between the two groups. Monofactorial analysis demonstrated that tumor size, lymph node state, American Joint Committee on Cancer stage, molecular subtypes and adjuvant chemotherapy treatment were prognostic factors in male breast cancer patients. The 5- and 10-year disease-free survival rates were 65.6 and 40.1% for males, and 74.9 and 51.5% for females, respectively. The 5- and 10-year overall survival rates were 72.9 and 53.9% for males, and 83.2 and 68.5% for females, respectively. There was significantly difference in disease-free survival and overall survival between the two matched groups (P = 0.002).

CONCLUSIONS

Male breast cancer patients had inferior outcome despite of equal stage in comparison with matched female breast cancer patients, which demonstrates that biological differences may contribute to the worse prognosis.

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.

Long CAG repeat sequence and protein expression of androgen receptor considered as prognostic indicators in male breast carcinoma

Background

The androgen receptor (AR) expression and the CAG repeat length within the AR gene appear to be involved in the carcinogenesis of male breast carcinoma (MBC). Although phenotypic differences have been observed between MBC and normal control group in AR gene, there is lack of correlation analysis between AR expression and CAG repeat length in MBC. The purpose of the study was to investigate the prognostic value of CAG repeat lengths and AR protein expression.

Methods

81 tumor tissues were used for immunostaining for AR expression and CAG repeat length determination and 80 normal controls were analyzed with CAG repeat length in AR gene. The CAG repeat length and AR expression were analyzed in relation to clinicopathological factors and prognostic indicators.

Results

AR gene in many MBCs has long CAG repeat sequence compared with that in control group (P = 0.001) and controls are more likely to exhibit short CAG repeat sequence than MBCs. There was statistically significant difference in long CAG repeat sequence between AR status for MBC patients (P = 0.004). The presence of long CAG repeat sequence and AR-positive expression were associated with shorter survival of MBC patients (CAG repeat: P = 0.050 for 5y-OS; P = 0.035 for 5y-DFS AR status: P = 0.048 for 5y-OS; P = 0.029 for 5y-DFS, respectively).

Conclusion

The CAG repeat length within the AR gene might be one useful molecular biomarker to identify males at increased risk of breast cancer development. The presence of long CAG repeat sequence and AR protein expression were in relation to survival of MBC patients. The CAG repeat length and AR expression were two independent prognostic indicators in MBC patients.

Are there biologic differences between male and female breast cancer explaining inferior outcome of men despite equal stage and treatment?!

BACKGROUND

Reasons for inferior outcome of male compared to female breast cancer are still under debate. Therefore, we retrospectively analyzed male breast cancer cases to figure out possible treatment- and gender-related differences.

PATIENTS AND METHODS

A total of 40 men (median age 62 years) were curatively treated with mastectomy and postoperative radiotherapy from 1982-2007. They presented predominantly in stages II and IIIb. Postoperative radiotherapy was applied with doses of 1.8-2.5 Gy to a median of 50 Gy including regional lymphatics in 22 patients. Adjuvant systemic treatment consisted of chemotherapy (22.5%) and antihormonal treatment (55%). For reasons of comparison, we estimated outcome of a virtual female matched cohort for no/equal to men/optimal adjuvant treatment with the Adjuvant!Online(®) 8.0 algorithm.

RESULTS

After a median follow-up of 47 months, the estimated 5-year local control rate was 97%, disease-free and distant metastasis-free survival rates reached 79% and 82%, respectively. With update of survival data by tumor registry, mean overall survival reached 120 months with 5- and 10-year overall survival rates of 66% and 43%, respectively. Predominant prognostic factor was T-stage for overall survival (T1/2 vs. T4: > 80% vs. 30%). The generated virtual matched cohorts of women with equal characteristics reached superior 10-year-overall survival for no/equal to men/optimal adjuvant treatment with 55/59/68%.

CONCLUSION

Compared to historical and virtual matched cohorts of women, male breast cancer patients had inferior outcome despite of equal stage and treatment which indicates that biological differences (of tumor or population) may contribute to worse prognosis.

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.

Intracystic Papillary Carcinoma of the Breast in Males. In Search of the Optimal Treatment for this Rare Disease

Intracystic papillary carcinoma (IPC) of the breast in men is an extremely infrequent disease, and it appears to have a good prognosis. Because of this, histological findings are of great importance in the decision-making process regarding treatment. Clinical examination, radiological and histological assessments are required for early detection. Adequate surgical excision with negative margins is mandatory. However, the role of sentinel node biopsy has not been evaluated in male IPC. It appears that sentinel node biopsy may be an excellent alternative to radical axillary dissection in patients with IPC and associated ductal carcinoma in situ or invasive carcinoma. Nevertheless, due to the rarity of IPC and its confusing histopathological classification and staging, there are still no clear guidelines as far as IPC treatment is concerned.

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.

Male breast cancer: a review of clinical management

AIMS

Male breast cancer incidence is 1% of all breast cancers and is increasing. We aim to present an overview of male breast cancer with particular emphasis on clinical management.

METHODS

Studies were identified by an online search of literature in the MEDLINE database till June 2006 followed by an extensive review of bibliographies.

RESULTS

Increased risk factors include genetic predisposition as in BRCA2 families; testicular dysfunction due to chromosomal abnormality such as Klinefelter's syndrome or environmental factors such as chronic heat exposure and radiation. Clinical assessment with biopsy is the hallmark of diagnosis. Earlier presentations are becoming commoner but there are wide geographical differences. Surgical treatment involves simple or modified radical mastectomy along with surgical assessment of the axilla, either via sentinel node biopsy in clinically node-negative disease or axillary sampling/clearance in node-positive disease. Reconstructions for restoring body image have been recently reported. Indications for adjuvant therapies are similar to that in women. For metastatic disease, tamoxifen is still the mainstay for oestrogen receptor positive disease. For oestrogen receptor negative disease, doxorubicin based chemotherapy regimens are used. In addition, the oft neglected psychological aspects of men having a "cancer of women" are increasingly being recognised.

CONCLUSIONS

There is, thus, need for further increasing awareness among men to reduce stigma associated with presentation of symptoms related to breast. This should be in addition to stressing to clinicians the ways of earlier detection and tailor-made "gender oriented" treatment of breast cancer in men.

Cancer du sein chez l'homme : existe-t-il une similitude avec le cancer du sein chez la femme ?

Male breast cancer is an uncommon disease although its incidence has increased over the recent years. Like other orphan diseases, male breast cancer is understudied. This disease has a lot of similarities with female breast cancer. Some differences are yet noticeable. This article describes three cases of carcinoma of the breast in men with a review of the literature on risk factors and treatment. A database must be started with epidemiologic information to understand this disease and its correlation with breast cancer in women.

Steroid hormone receptor expression in male breast cancer

AIMS

To investigate expression of the steroid hormone receptors estrogen receptor (ER)-alpha and -beta, progesterone receptor (PR) and androgen receptor (AR) in male breast cancer.

METHODS

Specimens from 16 male breast cancers were immunostained for ERalpha, ERbeta, PR and AR.

FINDINGS

Eighty-seven percent of tumours expressed ERalpha, 93% PR, 87% ERbeta and 87% AR. Staining for ERalpha and PR was confined exclusively to the nuclei of epithelial cells with some heterogeneity. Nuclear immunoreactivity was also observed with AR. Again this was restricted to epithelial cells but tended to be more uniform. ERbeta was seen in the nuclei of epithelial cells and also in stromal fibroblasts and lymphocytes. Analysis of serial sections revealed a similar pattern of staining with ERbeta and AR in epithelial cells.

CONCLUSIONS

In addition to expression of the better known steroid receptors, ERalpha, PR and AR, we have demonstrated a high rate of expression of ERbeta in male breast cancer. This is in keeping with the generally high steroid receptor expression seen in males. However, the abundance of ERbeta expressed in this small series of male breast cancer is in contrast to female breast cancer where ERbeta expression is often reduced.

A Review of the Diagnosis and Management of Male Breast Cancer

Male breast cancer is an uncommon disease although the incidence has increased over the past 25 years. As with many other rare "orphan" diseases, male breast cancer is understudied. The rarity of the disease precludes prospective randomized clinical trials. In addition, few researchers and minimal funding have focused on breast cancer in men, but further work is clearly needed to better understand this disease. It shares many similarities with breast cancer in women; yet some clear differences have emerged. In this article, the latest information on the epidemiology, biology, and treatment of male breast cancer is reviewed.

Frequent amplification and overexpression of CCND1 in male breast cancer

Genetic events underlying the pathogenesis of breast cancer have been studied extensively and several clinically significant markers have been identified. For example, amplification and overexpression of the ERBB2 oncogene is associated with poor prognosis in breast cancer and ERBB2 serves as a target for antibody-based therapy. Current knowledge on the pathogenesis of male breast cancer (MBC) is limited. The purpose of our study was to investigate the potential relevance of a series of genes known to be amplified in female breast cancer (FBC) in a the development and pathogenesis of MBC. To this end, we applied fluorescence in situ hybridization and immunohistochemistry to the analysis of 128 breast tumors from males. Amplification of ERBB2, MYC, PPM1D and ZNF217 was detected rarely (1-2% of tumors) indicating a considerably lower amplification frequency than in FBC. CCND1 amplification was observed in 12% of cases, being in good concordance with findings from FBC. In addition, CCND1 overexpression was detected in 63% of tumors and was associated with ER positivity (p < 0.0001). Our results indicate distinct differences in the genetic basis of MBC and FBC and suggest that marked differences exist in the pathogenesis of these diseases. The lack of ERBB2 involvement was especially unexpected and implies that ERBB2-targeted therapies are unlikely to be beneficial in MBC. Furthermore, the high frequency of hormone receptor positivity and the association between ER positivity and CCND1 overexpression supports the notion that hormonal regulation is likely to be essential for the development of MBC.

Androgen and vitamin D receptor expression in archival human breast tumors

BACKGROUND

The present study was undertaken for quantitation of androgen (AR) and vitamin D (VDR) receptor expression in human male and female breast tumors by flow cytometry.

METHODS

Nuclei isolated from sections of paraffin-embedded tumors by pepsin digestion were treated for antigen unmasking and incubated with antibodies to AR and VDR. Flow cytometric analysis was used to determine the percentage of receptor-positive nuclei with fluorescence greater than 95% of the isotype nuclei. Mean log fluorescence channel values were used for comparing antigen density of the isotype and the antibody-treated nuclei.

RESULTS

Six of 23 female breast tumors had aneuploid DNA content. Nineteen of 20 estrogen receptor-positive female tumors by immunohistochemical analysis (IHC) were also AR positive by flow analysis. Aneuploid subpopulations had higher percentages of AR-positive nuclei than did diploid populations. Eight of 33 male breast tumors had aneuploid DNA content. Twenty-three of 33 male breast tumors were AR positive by flow analysis compared with six that were AR positive by IHC. Six AR-positive (IHC) male tumors were also AR positive by flow analysis. VDR expression was higher in diploid female tumors than in aneuploid tumors.

CONCLUSIONS

Lack of a strong correlation between IHC and flow analysis may be due to differences in criteria used for identification of receptor-positive and -negative tumors by the two methods.

Expression of androgen receptor and prostate-specific antigen in male breast carcinoma

BACKGROUND

The androgen-regulated proteins prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP) are present in high concentrations in normal prostate and prostatic cancer and are considered to be tissue-specific to prostate. These markers are commonly used to diagnose metastatic prostate carcinoma at various sites including the male breast. However, expression of these two proteins in tumors arising in tissues regulated by androgens such as male breast carcinoma has not been thoroughly evaluated.

METHODS

In this study we analyzed the expression of PSA, PSAP and androgen receptor (AR) by immunohistochemistry in 26 cases of male breast carcinomas and correlated these with the expression of other prognostic markers.

RESULTS

AR, PSA and PSAP expression was observed in 81%, 23% and 0% of carcinomas, respectively. Combined expression of AR and PSA was observed in only four tumors.

CONCLUSION

Although the biological significance of PSA expression in male breast carcinomas is not clear, caution should be exercised when it is used as a diagnostic marker of metastatic prostate carcinoma.

Detection and purification of a novel 72 kDa glycoprotein male breast tumor associated antigen

A male breast tumor associated antigen (MBTAA) was purified and partially characterized from human male breast tumor. Three protein peaks were obtained by DEAE-cellulose column chromatography of a crude extract of human male breast tumor tissues. Circulating antibodies against one of these peaks, MF1, which contained MBTAA, were observed in male breast cancer patients but not in normal male or male patients with carcinoma of other organs (stomach, colon, lung). The MBTAA was partially purified from MF1 by subjecting the fraction to SDS-PAGE and eluting the protein from band 3 (MB-3) and by subjecting MF1 to size exclusion-high performance liquid chromatography (SE-HPLC). The MBTAA was characterized as a glycoprotein with MW of approximately 72 kDa. It showed no immunological relatedness with TAG-72, a tumor associated antigen expressed in breast epithelial cells. A 72 kDa protein, immunologically related to MBTAA, was detected and partially purified from female breast tumor. The female breast cancer patients did not have circulating antibodies against this 72 kDa protein or MBTAA. Presence of 72 kDa glycoprotein MBTAA in MF1 and specificity of the anti-MBTAA antibodies in the sera of male breast cancer patients were further confirmed by Western blot analysis. Absence of anti-MBTAA antibodies in healthy men and in patients with other cancers suggested that expression of MBTAA may be malignancy-associated and is highly overexpressed in male breast cancer.

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.

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.

Oncogenes and male breast carcinoma: c-erbB-2 and p53 coexpression predicts a poor survival

PURPOSE

To investigate the prognostic value of biomarkers in male breast carcinoma (MBC).

PATIENTS AND METHODS

Fifty patients (mean age, 62.2 years) with invasive ductal carcinoma were retrospectively studied. All patients received surgery; 35 had adjuvant postoperative therapy. The median follow-up was 59 months (range, 1 to 230 months). c-myc, c-erbB-2, p53, and bcl-2 proteins were immunohistochemically detected on sections from formalin-fixed, paraffin-embedded tissues using 9E11, CB11, DO7, and bcl-2 124 monoclonal antibodies (mAbs). Estrogen, progesterone, and androgen receptors were detected using specific mAbs. Cell proliferation was assessed by MIB-1 mAb.

RESULTS

In univariate analysis, c-myc, c-erbB-2, and p53 protein overexpression was significantly correlated with prognosis. The median survival was 107 months for c-myc-negative and 52 months for c-myc-positive patients (P =.01), 96 months for c-erbB-2-negative and 39 months for c-erbB-2-positive patients (P =.02), and 100 months for p53-negative and 33 months for p53-positive patients (P =.0008). Tumor histologic grade (P =.01), tumor size (P =.02), patient age at diagnosis (P =.03), and MIB-1 scores (P =.0004) also had prognostic value. In multivariate analysis, only c-erbB-2 and p53 immunoreactivity retained independent prognostic significance. All nine patients who did not express c-erbB-2 and p53 proteins were alive after 58 months, whereas none of the 14 patients expressing both proteins survived at 61 months follow-up (P =.0002).

CONCLUSION

Overexpression of c-myc, c-erbB-2, and p53 proteins may be regarded as an additional prognostic factor in MBC. The combination of c-erbB-2 and p53 immunoreactivity can stratify patients into different risk groups.

Expression of androgen receptor and prostatic specific markers in salivary duct carcinoma: an immunohistochemical analysis of 13 cases and review of the literature

Salivary duct carcinoma (SDC) is an uncommon, pathologically distinct entity characterized by its morphologic resemblance to ductal carcinoma of the breast and highly aggressive behavior. Approximately two thirds of patients die within 4 years of initial diagnosis despite aggressive, combined surgical resection and radiotherapy. Review of the literature indicates that androgen receptor (AR), a marker frequently detected in prostatic carcinoma, is expressed in over 90% of SDCs, whereas two common breast carcinoma markers, estrogen and progesterone receptors (ER and PR), are expressed in only 1.3% and 6% of the tumors, respectively, by immunohistochemistry. This hormonal profile suggests that SDC, in contrast to its histiologic similarity to ductal carcinoma of the breast, is immunophenotypically more related to prostatic carcinoma. To substantiate this hypothesis, we performed immunohistochemical staining of 13 cases of SDC for the presence of AR and two prostatic markers, prostate specific antigen (PSA) and prostatic acid phosphatase (PAP). Our results showed multifocal, scattered, moderate immunostaining for PAP and diffuse, moderate immunostaining for PSA in seven (58.3%) and two (16.7%) cases, respectively. These results create a potential diagnostic challenge to surgical pathologists who are dealing with a metastatic adenocarcinoma of AR+/PSA+/-/PAP+/- phenotype, particularly in male patients of unknown primary. Metastatic salivary duct carcinoma should be given serious thought if clinical investigation fails to reveal a prostatic primary. The immunophenotypic homology that exists between SDC and prostatic carcinoma also suggests that antiandrogen therapy as used in the treatment of prostatic carcinoma might be beneficial in patients with metastatic SDC when all other conventional modalities fail.