Prognostic factors in male breast cancer: a population-based study

Omission of adjuvant radiotherapy in low-risk elderly males with breast cancer

PURPOSE

Randomized clinical trials demonstrate that lumpectomy + hormone therapy (HT) without radiation therapy (RT) yields equivalent survival and acceptable local-regional outcomes in elderly women with early-stage, node-negative, hormone-receptor positive (HR +) breast cancer. Whether these data apply to men with the same inclusion criteria remains unknown.

METHODS

The National Cancer Database was queried for male patients ≥ 65 years with pathologic T1-2N0 (≤ 3 cm) HR + breast cancer treated with breast-conserving surgery with negative margins from 2004 to 2019. Adjuvant treatment was classified as HT alone, RT alone, or HT + RT. Male patients were matched with female patients for OS comparison. Survival analysis was performed using Cox regression and Kaplan - Meier method. Inverse probability of treatment weighting (IPTW) was applied to adjust for confounding.

RESULTS

A total of 523 patients met the inclusion criteria, with 24.4% receiving HT, 16.3% receiving RT, and 59.2% receiving HT + RT. The median follow-up was 6.9 years (IQR: 5.0-9.4 years). IPTW-adjusted 5-yr OS rates in the HT, RT, and HT + RT cohorts were 84.0% (95% CI 77.1-91.5%), 81.1% (95% CI 71.1-92.5%), and 93.0% (95% CI 90.0-96.2%), respectively. On IPTW-adjusted MVA, relative to HT, receipt of HT + RT was associated with improvements in OS (HR: 0.641; p = 0.042). RT alone was not associated with improved OS (HR: 1.264; p = 0.420).

CONCLUSION

Among men ≥ 65 years old with T1-2N0 HR + breast cancer, RT alone did not confer an OS benefit over HT alone. Combination of RT + HT demonstrated significant improvements in OS. De-escalation of treatment through omission of either RT or HT at this point should be done with caution.

The Association between ER, PR, HER2, and ER-/PR+ Expression and Lung Cancer Subsequent in Breast Cancer Patients: A Retrospective Cohort Study Based on SEER Database

Aims

The available research on the association between estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), ER-/PR+ status, and the occurrence of lung cancer subsequent to breast cancer in patients (referred to as BC-LuC) had been limited. Consequently, there is a need to examine whether ER, PR, HER2, and ER-/PR+ have independent correlations with the risk and outcomes of BC-LuC, while appropriately adjusting for other potential covariates.

Methods

The present study employed a cohort design and utilized data from the Surveillance, Epidemiology, and End Results (SEER) program spanning from 2010 to 2015. The study population consisted of 683,336 individuals who were diagnosed with breast cancer (referred to as BC). Various covariates were assessed at baseline, including age, sex, race, marital status, CS tumor size, laterality, radiation, chemotherapy, months from diagnosis to treatment, breast subtype, AJCC 7th edition (2010-2015), and combined summary stage (2004+). The primary objective of this study was to investigate the association between ER, PR, HER2, ER-/PR+ status, and the risk of developing BC-LuC. Logistic regression analysis was employed to assess this association. Furthermore, multivariable Cox regression analyses were conducted to calculate adjusted hazard ratios (HRs) along with their respective 95% confidence intervals (CIs). Kaplan-Meier plots and log-rank tests were utilized to estimate the outcomes, specifically overall survival (OS), disease-specific survival (DSS), and metastasis.

Results

The average age of 198,972 selected participants was 59.8 ± 13.1 years, and about 99.3% of them were female. Result of fully adjusted binary logistic regression showed PR+ and HER2+ were positively associated with lower risk BC-LuC after adjusting confounders (ORs = 0.84, 95% CI: 0.73-0.96, p = 0.011 and ORs = 0.83, 95% CI: 0.72-0.96, p = 0.012, respectively). ER+ and ER-/PR+ were detected no significant relationship with BC-LuC (ORs = 1.03, 95% CI: 0.87-1.22, p = 0.718 and ORs = 1.02, 95% CI: 0.61-1.72, p = 0.936, respectively). In subgroups analyses, the results remain stable. Multivariable Cox regression showed that BC-LuC patients with ER and PR were significantly associated with OS and DSS. However, ER, PR, HER2, and ER-/PR+ were significantly associated with OS and DSS in breast cancer patients. The relationship between ER, PR, HER2, and ER-/PR+ and metastasis in breast cancer patients was different.

Conclusion

The results of this study indicated a potential correlation between PR- and HER2- status and a risk of developing BC-LuC. Furthermore, it appears that the prognosis of BC-LuC may be influenced by the presence of ER+ and PR+. Therefore, additional research is warranted to fully investigate and validate this association.

Clinicopathologic characteristics and prognostic factors in patients with male breast cancer: A single tertiary center experience

BACKGROUND

The goal of this study was to assess the clinicopathologic characteristics and prognostic variables in men with breast cancer (BC).

METHODS

Clinical features, pathological characteristics, stage at diagnosis, and therapy data were noted. Survival analysis was performed using the log-rank technique and Cox regression model.

RESULTS

Eighty patients were included in the study. In 31% of the individuals, BRCA (BReast CAncer genes 1 and 2) mutations were identified. The estrogen receptor (ER) positivity ratio was 93.6%, whereas the progesterone receptor (PR) positivity ratio was 74.4%. In 16.9% of the cases, HER2 overexpression was found. The median survival time was 120.9 months (70.3-171.5), and the five-year overall survival (OS) ratio was 74.9%. In univariate analysis, BRCA mutation status had no effect on OS (P = 0.50). CA15-3 levels (P = 0.03) at diagnosis and history of smoking (P = 0.03) were significantly linked with OS. However, the multivariate analysis could not confirm these results.

CONCLUSIONS

We found that BRCA mutation, body mass index, a history of smoking, and alcohol consumption did not affect the OS in this research.

A Novel Nomogram for Predicting Breast Cancer-specific Survival in Male Patients

OBJECTIVES

To compare breast cancer-specific survival (BCSS) of nonmetastatic invasive breast cancer between male (MBC) and female (FBC) patients, define clinicopathologic variables related to BCSS in nonmetastatic invasive MBC patients, and establish a nomogram for individual risk prediction.

MATERIALS AND METHODS

On the basis of Surveillance, Epidemiology, and End Results database, 2094 MBC and 48,104 FBC cases underwent propensity score matching (PSM). We compared the prognosis of patients before and after PSM and developed a nomogram for BCSS of nonmetastatic invasive MBC patients. Internal validation was performed using the consistency index, calibration curves, and receiver operating characteristic curves. Simultaneously, data from 49 nonmetastatic invasive MBC patients diagnosed between January 2012 and May 2016 were collected for external validation.

RESULTS

Before PSM, overall survival and BCSS were significantly shorter in MBC than those in FBC patients. After PSM, MBC patients continued to have a shorter overall survival, but not BCSS, than FBC patients. Marital status, age, histologic grade, estrogen/progesterone receptor status, Tumor Lymph Node stage, and surgery were included in the prediction model.

CONCLUSIONS

The nomogram developed in this study seems to be more accurate than conventional Tumor-nodal-metastasis staging staging to predict BCSS and may serve as an effective tool for assessing the prognosis of nonmetastatic invasive MBC.

Male breast cancer: a 20-year multicenter experience

Aim: Male breast cancer (MBC) is a rare disease and accounts for approximately 1% of breast cancer. Treatment is largely extrapolated from female breast cancer due to lack of data in MBC. However, there are distinct features of MBC that warrant different treatment approach. We aim to better characterize the risk factors, clinicopathologic features, treatment and outcome of MBC patients from six hospitals across Steward Healthcare Network. Materials & methods: A total of 107 men with breast cancer were identified from the respective cancer registry at Steward and 64 patients were included with complete medical records. Their clinical, histopathological and treatment records were retrospectively reviewed. Kaplan–Meier method was used to determine the 5, 10 year overall survival (OS) rate and relapse free survival rate and Cox Regression test was used to assess the association between patient outcome and age at diagnosis, metastasis status at time of diagnosis, tumor size, nodal involvement and use of chemotherapy. Results: Of these 64 patients, median age at diagnosis was 68 years, majority of patients were white, 13 patients had family history of breast or ovarian cancer (20.3%), four patients tested positive for BRCA2 (6.25). Majority of patients presented painless breast lump. A total of 59 patients (92.2%) had invasive ductal carcinoma, and 31 patients (48.4%) had lymph node involvement at time of diagnosis. A total of 62 patients (96.8%) had M0 disease at time of diagnosis. About 97% of patients had estrogen receptor (ER) positive cancer. Most patients underwent mastectomy (87.5%), 35 patients (54.6%) received adjuvant radiation therapy, 19 patients (30%) received adjuvant chemotherapy and 96.7% of patients received adjuvant hormonal therapy. The median follow-up was 71.5 months (range 6–250 months), 5-year survival rate was 86.9% (95% CI: 74.5–93.6%), 5-year relapse free survival rate was 89.9% (95% CI: 77.4–95.7%) and 10-year survival rate was 58.1% (95% CI: 41.0–71.8%). The presence of distant metastasis at the time of initial diagnosis was the only factor associated with shorter OS (hazard ratio: 22.54, p < 0.0001). Conclusion: Majority of MBC patients present with palpable breast mass and the tumors are almost exclusively hormone receptor positive. Majority of patients present without distant metastasis and received surgical therapy; however, only a small subset of patients received breast conserving surgery for T1 tumor. Almost all patients received adjuvant hormonal therapy. OS and relapse free survival in our cohort is similar to historic reports in female breast cancer.

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.

Prognostic difficulties of men with breast cancer

Most adequately powered studies confirm a worse prognosis for males versus matched females with breast cancer. There is in-stage migration for stage I cancers with a different ratio of tumor/normal breast tissue in males. Younger men have a better prognosis, largely the result of increased morbidity in the elderly, exacerbated by smoking, low socioeconomic differences, and ethnic disparity. BRCA2 carriers with MBC have a worse outcome than noncarriers as do men with amplification of EMSY. Men with tumors having a high cytosol level of plasminogen activator inhibitor 1 (PAI-1) may have more invasive cancers leading to earlier spread and hence a worse outcome. PREDICT+ is a useful prognostic model for MBC and multigene testing enables more specific systemic therapies to be used.

Refusal of cancer-directed surgery in male breast cancer

It has been reported that some male breast cancer patients may refuse the recommended surgery, but the incidence rate in the United States is not clear. The purpose of this study was to identify the incidence, trends, risk factors, and eventual survival outcomes associated with the rejection of such cancer-directed surgery.We collected data on 5860 patients with male breast cancer (MBC) from the Surveillance, Epidemiology, and End Results database, including 50 patients refusing surgery as recommended. Kaplan-Meier survival analysis and Cox proportional hazard regression were used to identify the effects of refusing surgery on cancer-specific survival (CSS) and overall survival (OS). The association between acceptance or rejection of surgery and mortality were estimated by nested Cox proportional hazards regression models with adjustment for age, race, clinical characteristics, and radiation.Of the 5860 patients identified, 50 (0.9%) refused surgery. Old age (≥65: hazard ratio [HR]: 3.056, 95% confidence interval [CI]: 1.738-5.374, P < .0001), higher AJCC stage (III: HR: 3.283, 95% CI: 2.134-5.050, P < .0001, IV: HR: 14.237, 95% CI: 8.367-24.226, P < .0001), progesterone receptor status (negative: HR: 1.633, 95% CI: 1.007-2.648, P = .047) were considered risk factors. Compared with the surgery group, the refusal group was associated with a poorer prognosis in both OS and CSS (χ2 = 94.81, P < .001, χ2 = 140.4, P < .001). Moreover, significant differences were also observed in OS and CSS among 1:3 matched groups (P = .0002, P < .001).Compared with the patients undergoing surgery, the patients who refused the cancer-directed surgery had poor prognosis in the total survival period, particularly in stage II and III. The survival benefit for undergoing surgery remained even after adjustment, which indicates the importance of surgical treatment before an advanced stage for male breast cancer patients.

The use of adjuvant radiation therapy in male breast cancer and its impact on outcomes

BACKGROUND

Male breast cancer (MBC) accounts for 1% of all breast cancers and there is a paucity of data on factors impacting the treatment strategies and outcomes. We sought to use a large national database to examine trends and predictors of the use of adjuvant radiation (Adj-RT), as well as any association with outcome.

METHODS

We queried the National Cancer Database (NCDB) for patients with stages I-III MBC treated with surgery (breast conservation surgery-BCS or mastectomy-MS) within 180 days of diagnosis (years 2004-2015). Multivariable logistic regression identified predictors of adj-RT receipt. Multivariable Cox regression evaluated predictors of survival. Propensity matching for adj-RT was used to account for indication biases.

RESULTS

We identified 6,217 patients meeting the eligibility criteria (1457 BCS vs. 4760 MS). The majority of patients were Caucasian (85%) and in an age range of 50-80 years (74%). Although adj-RT was omitted for 30% of BCS patients, the utilization was higher compared to MS (OR=26, p-value=0.001). The predictors of adj-RT use included African-American race, more advanced stage, higher grade, presence of lymphovascular invasion, and ER/Her-2 positivity for the entire cohort and increased age, urban location and higher income for BCS. Adj-RT was associated with lower mortality in the propensity matched model (overall HR for BCS=0.28, p-value<0.001; overall HR for MS=0.62, p-value=0.001).

CONCLUSION

This study demonstrates that while adj-RT after BCS is associated with decreased mortality in MBC patients, adj-RT is omitted in up to a third of cases of MBC after BCS despite being standard of care.

The prognostic significance of metastatic pattern in stage IV male breast cancer at initial diagnosis: a population-based study

PURPOSE

Metastatic pattern (MP) is a prognostic factor in women with breast cancer. However, the prognostic significance of MP in male breast cancer patients remains unknown.

METHODS

Using the SEER database, we gathered demographic information and disease characteristics for men diagnosed with de novo metastatic breast cancer from 2010 to 2017. Metastases to bone, brain, liver, and lung were used to define MP (bone-only, visceral, bone and visceral [BV], or other). Statistical analyses were performed to identify associations between overall survival (OS) and MP, as well as other patient and tumor features. We used multivariate logistic regression to evaluate factors associated with sites of metastases.

RESULTS

We included 250 patients. MP distribution was bone = 38.8%, visceral = 14.8%, BV = 33.2%, and other = 13.2%. Median OS for each was bone = 33 months, visceral = 23 months, BV = 20 months, and other = 46 months (p = 0.046). Patients with brain metastases had significantly shorter OS compared with no brain metastases (median OS = 9 months vs. 30 months; p < 0.001). Compared with other subtypes, triple negative had the shortest OS (median 9 months, p < 0.001). Logistic regression modeling revealed that compared with HR+/HER2- breast cancers, HR-/HER2+ had higher odds of liver metastases and triple negative had higher odds of brain metastases. Patients younger than 50 years had a significantly greater risk of developing brain metastases.

CONCLUSIONS

MP and tumor subtype can predict OS outcomes in men with metastatic breast cancer at diagnosis. Brain metastases confer very poor prognosis.

Epidemiology of male breast cancer

Background

Due to its rarity, few studies have characterized the epidemiology of male breast cancer. The purpose of this study was to determine survival and risk factors for male breast cancer in a large U.S. population.

Methods

In this study, 19,795 male patients with breast cancer were identified from the National Cancer Database (2004–2014). Patient demographics, tumor characteristics and treatments were analyzed by using descriptive statistics. We used multivariate Cox regression and Kaplan Meier analysis.

Results

Over 10 years, the incidence of male breast cancer increased from 7.2% to 10.3%, while mortality decreased from 11% to 3.8%. Socioeconomic factors predicting mortality included income medium, and high vs low (HR = 0.78; 0.68), private vs no insurance (HR = 0.73) and the academic research facility vs community cancer center (HR = 0.79). Significant predictors of all-cause mortality included age (HR = 1.04), tumor size (HR = 1.01), hormone receptor expression (HR = 0.8) and cancer stage I vs II, III, and IV at the time of diagnosis (HR = 1.5, 2.7, 4.4, 9.9 respectively). Other predictors of mortality include surgery (HR = 0.4), chemotherapy (HR = 0.8), radiation (HR = 0.8), and hormonal therapy (HR-0.8).

Conclusions

Socioeconomic factors, cancer stage, tumor characteristics (size and grade), and high Charlson-Dayo score contributed to higher mortality among male patients diagnosed with breast cancer. Surgery was most effective, followed by radiation, chemotherapy, and hormonal therapy. Patients with positive ER or PR expression demonstrated better survival. Adjusting for socioeconomic factors, biomarker identification and timely, appropriately chosen treatment are likely to reduce the risk for mortality.

1

Mortality was higher among patients with Low income and with no insurance.

2

Patients with positive ER or PR expression demonstrated better survival.

3

Surgery, chemotherapy, radiation, and hormonal therapy improved survival.

Prognostic Value of the Neutrophil-Lymphocyte, Platelet-Lymphocyte, and Monocyte-Lymphocyte Ratios in Male Breast Cancer Patients

BACKGROUND

The aim of the present study was to assess the blood neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and monocyte-lymphocyte ratio (MLR) as prognostic factors in male breast cancer (BC) patients.

METHODS

A retrospective analysis of 38 male BC patients who were treated at the Institute of Oncology (Gliwice, Poland) between January 2005 and December 2018 was performed. The prognostic value (in terms of overall survival [OS]) of the pretreatment PLR, NLR, and MLR was assessed by univariate analysis.

RESULTS

We observed a tendency towards worse OS among male BC patients with lymph node metastases (N+) (5-year OS: 43.5 vs. 73.9%; p = 0.087), a greater tumor size (T4 vs. T1 + T2) (42.0 vs. 70.5%; p = 0.061), and a negative steroid receptor status (PR-) (28.6 vs. 65.6%; p = 0.109). Patients with a family history of cancer had significantly better 5-year OS than patients without a family history of cancer (86.3 vs. 35.0%; p = 0.001). Younger male BC patients (age ≤56 years) had better 5-year OS than patients >56 years of age (82.5 vs. 42.3%; p = 0.028). The 5-year OS was lower among patients with a lower lymphocyte value (≤1.82 × 103) (29.0 vs. 75.6%; p = 0.010). There was a tendency towards worse OS among patients with a higher platelet count (>281 × 103) (4.5-year OS: 16.7 vs. 65.8%; p = 0.056). The 5-year OS was insignificantly lower in the group with NLRs >2.74 than in the group with NLRs ≤2.74 (37.5 vs. 62.8%; p = 0.078). A worse OS rate was associated with an elevated PLR (>169.1) (22.2 vs. 70.1%; p = 0.008). Similarly, there was worse OS in the group with higher MLR (>0.30) (41.8 vs. 78.3%; p = 0.025).

CONCLUSIONS

The present results reveal that elevated MLRs (>0.30) and PLRs (>169.1) are associated with poor OS among male BC patients. Similarly, but insignificantly, an elevated NLR (>2.74) affected OS.

Metastasis pattern and prognosis of male breast cancer patients in US: a population-based study from SEER database

Background

The aims of this study were to analyze the metastasis pattern and prognosis of male breast cancer (MBC) and compare it with female breast cancer (FBC), and to determine the independent factors affecting the prognosis of MBC patients.

Methods

Metastatic MBC diagnosed in the Surveillance, Epidemiology and End results (SEER) database from 2010 to 2015 were selected. Chi-squared test was used to compare clinicopathological characteristics. Survival differences were compared by Kaplan-Meier analysis. Cox proportional hazard model was used to determine the prognostic factors affecting overall survival.

Results

A total of 2754 MBC patients were identified, of which 196 had distant metastasis. Compared with nonmetastatic MBC, metastatic MBC patients had a higher proportion of <60 years old and grade III-IV, and were more likely to receive chemotherapy and radiotherapy, while the proportion of surgery, central portion of the breast, and Her2-/HR+ was lower. Compared with metastatic FBC, metastatic MBC patients had a higher proportion of ⩾60 years old, central portion of the breast, surgery, simultaneous bone and lung metastasis, while the proportion of Her2+/HR-, triple negative, liver metastasis only, and simultaneous bone and liver metastasis was lower. MBC patients with lung alone, bone alone, and simultaneous lung and bone metastasis had a higher hazard ratio (2.41; 3.06; 2.52; p < 0.0001) compared with nonmetastatic patients.

Conclusions

Compared with nonmetastatic MBC patients, metastatic MBC patients had unique clinicopathological features, and were also different from metastatic FBC patients. However, there was no difference in prognosis between metastatic MBC and FBC patients. Distant metastasis was an independent risk factor for the prognosis of MBC patients.

Overall Survival of Men and Women With Breast Cancer According to Tumor Subtype: A Population-based Study

OBJECTIVES

To analyze differences in overall survival (OS) between male breast cancer (MBC) and female breast cancer (FBC) according to tumor subtype compared with other factors.

MATERIALS AND METHODS

We evaluated men and women with breast cancer between 2010 and 2013 with known hormone receptor (HR) status and human epidermal growth factor receptor 2 (HER2) status reported to the National Cancer Institute's Surveillance, Epidemiology, and End Results program. Patient characteristics were compared between groups. Univariate and multivariate analyses were performed to determine the effect of each variable on OS. Breast cancer-specific survival was a secondary endpoint.

RESULTS

We included 1187 MBC and 166,054 FBC. Median follow-up was 21 months (range, 1 to 48) for both groups. OS at 3 years for MBC and FBC was 85.6% and 90.4%, respectively (P=0.0002). MBC were more ductal, had higher grade, presented with more advanced stage and were often HR+/HER2- (each P<0.0001). MBC had worse OS than FBC in HR+/HER2- (Hazard ratio [HaR], 1.5; P=0.0005), HR+/HER2+ (HaR, 2.8; P<0.0001) and triple negative (HaR, 4.3; P<0.0001) (Pinteraction<0.02). MBC had significantly worse OS than FBC in stages I and II, but similar OS in stages III and IV (Pinteraction<0.01). In multivariate analysis, HR+/HER2+ was the only subtype with significant differences in OS between MBC and FBC (HaR, 2.0; P=0.002).

CONCLUSIONS

OS was significantly different in both groups. Men had worse OS in early stages while similar OS in stages III and IV. There were significant differences in OS according to tumor subtype; compared with women, men with HR+/HER2+ tumors had twice the risk of death.

Male breast cancer: Specific biological characteristics and survival in a Portuguese cohort

Male breast cancer (BC) represents an individual subtype of BC, with therapeutic procedures based on female BC therapy results. The present study evaluated the parameters currently used for the characterization and therapy of male BC, and their association with disease-free (DFS) and overall survival (OS), aiming to obtain a comprehensive basis to improve the personalized care of male BC. A total of 196 patients from March 1970 to March 2018 (mean follow-up, 84.9 months) were profiled, using clinicopathological review, molecular assessment [BRCA1/2, DNA repair associated (BRCA1/2) status, immunohistochemistry, fluorescence in situ hybridization and DNA flow cytometry] and Cox regression statistical analysis. The median age of patients was 66.5 years. At presentation, 39.2% of patients with invasive carcinomas were in anatomic stage (AS) I. Patients exhibited primarily invasive carcinomas of no special type, histological grade 2, estrogen receptor α-(ERα) and progesterone receptor (PR)-positive, receptor tyrosine kinase erbB-2-negative, high Ki-67, Luminal B-like and aneuploid tumors. A total of 13 of the 44 (29.5%) BRCA-evaluated patients exhibited BRCA2 mutations, significantly associated with family history (FH), bilaterality, high Ki-67 expression, absence of PR and Luminal B-like tumors. Bilaterality was associated with the occurrence of non-breast primary neoplasms (NBPN). The 5 and 10-year DFS rates, excluding patients with distant metastasis, NBPN and in situ carcinomas (n=145) were 65.9 and 58.2%, respectively, and the 5 and 10-year OS rates were 77.5 and 59.2%, respectively. In the univariate analysis, Luminal B-like subtype, BRCA2 mutations, high Ki-67 expression, and AS II and III were significantly associated with shorter DFS and OS. In addition, age >70 years was associated with low OS. In the multivariate analysis, FH, AS II and III, and Luminal B-like subtypes were associated with poorer OS. In conclusion, the data from the present study emphasize the high incidence of BRCA2 mutation in male BC, and its association with FH, bilaterality, high Ki-67 expression, negative PR expression and Luminal B-like subtypes, and with shorter DFS and OS in univariate analysis.

Nomogram Predicting Cause-Specific Mortality in Nonmetastatic Male Breast Cancer: A Competing Risk Analysis

Introduction: Male breast cancer (MBC) is a rare tumor with few cases for research. Using the Surveillance, Epidemiology, and End Results program database, we carried out a competing risk analysis in patients with primary nonmetastatic MBC and built a predictive nomogram. Materials and Methods: We extracted primary nonmetastatic MBC patients according to the inclusion and exclusion criteria. Cumulative incidence function (CIF) and proportional subdistribution hazard model were adopted to explore risk factors for breast cancer-specific death (BCSD) and other cause-specific death (OCSD). Then we built a nomogram to predict the 3-year, 5-year and 8-year probabilities of BCSD and OCSD. C-indexes, Brier scores and calibration curves were chosen for validation. Results: We identified 1,978 nonmetastatic MBC patients finally. CIF analysis showed that the 3-year, 5-year and 8-year mortalities were 5.2%, 10.6% and 16.5% for BCSD, and 6.1%, 9.6% and 14.4% for OCSD. After adjustment of Fine and Gray models, black race, PR (-), advanced T/N/grade and no surgery were independently associated with BCSD. Meanwhile, elderly, unmarried status, advanced AJCC stage and no chemotherapy resulted in OCSD more possibly. A graphic nomogram was developed according to the coefficients from the Fine and Gray models. The calibration curves displayed exceptionally, with C-indexes nearly larger than 0.700 and Brier scores nearly smaller than 0.100. Conclusion: The competing risk nomogram showed good accuracy for predictive prognosis in nonmetastatic MBC patients. It was a useful implement to evaluate crude mortalities of BCSD and OCSD, and help clinicians to choose appropriate therapeutic plans.

Characterization and prognosis of estrogen receptor-positive/progesterone receptor-negative male breast cancer: a population-based study

Background

The aim of this study was to explore the characteristics and prognostic information of estrogen receptor-positive/progesterone receptor-negative (ER+/PR−) male breast cancer.

Methods

Using the US National Cancer Institute’s Surveillance, Epidemiology, and End Results database, we compared the demographics, clinical characteristics, and outcome of estrogen receptor-positive/progesterone receptor-positive (ER+/PR+) patients with ER+/PR− male breast cancer patients from 1990 to 2010. Two thousand three hundred twenty-two patients with ER+/PR+ tumors and 355 patients with ER+/PR− tumors were included in our study.

Results

ER+/PR− patients were younger (P = 0.008) and more likely to be African American (P < 0.001) while presented with higher histological grade (P < 0.001), larger tumor size (P = 0.010), and more invasion to the lymph nodes (P = 0.034) and distant sites (P < 0.001), thus later stage (P = 0.001). Despite higher chance of receiving chemotherapy (51.0% vs 36.5%, P < 0.001), ER+/PR− patients experienced significantly worse breast cancer-specific survival (BSCC) (P < 0.001) and shorter overall survival (OS) (P = 0.003). Multivariate Cox model confirmed that tumor size, lymph node invasion, metastasis, and surgery were independent prognostic factors of both BSCC and OS for ER+/PR− male breast cancer. Age at diagnosis and chemotherapy were significantly associated with OS but not with BSCC.

Conclusion

ER+/PR− male breast cancer was more aggressive and experienced shorter survival than ER+/PR+ patients. The prognosis was mainly associated with tumor size, lymph node invasion, metastasis, and surgery.

PD-1 and PD-L1 Expression in Male Breast Cancer in Comparison with Female Breast Cancer

BACKGROUND

Male breast cancer is rare, as it represents less than 1% of all breast cancer cases. In addition, male breast cancer appears to have a different biology than female breast cancer. Programmed death-1 (PD-1) and its ligand, programmed death-ligand 1 (PD-L1), seem to have prognostic and predictive values in a variety of cancers, including female breast cancer. However, the role of PD-1 and PD-L1 expression in male breast cancer has not yet been studied.

OBJECTIVES

To compare PD-1 and PD-L1 expression in male breast cancer to female breast cancer and to evaluate prognostic values in both groups.

PATIENTS AND METHODS

Tissue microarrays from formalin-fixed paraffin-embedded resection material of 247 female and 164 male breast cancer patients were stained for PD-1 and PD-L1 by immunohistochemistry.

RESULTS

PD-1 expression on tumor-infiltrating lymphocytes was significantly less frequent in male than in female cancers (48.9 vs. 65.3%, p = 0.002). In contrast, PD-L1 expression on tumor and immune cells did not differ between the two groups. In male breast cancer, PD-1 and tumor PD-L1 were associated with grade 3 tumors. In female breast cancer, PD-1 and PD-L1 were associated with comparably worse clinicopathological variables. In a survival analysis, no prognostic value was observed for PD-1 and PD-L1 in either male and female breast cancer. In a subgroup analysis, female patients with grade 3/tumor PD-L1-negative or ER-negative/immune PD-L1-negative tumors had worse overall survival.

CONCLUSIONS

PD-1 seems to be less often expressed in male breast cancer compared to female breast cancer. Although PD-1 and PD-L1 are not definite indicators for good or bad responses, male breast cancer patients may therefore respond differently to checkpoint immunotherapy with PD-1 inhibitors than female patients.

Clinical features of patients with male breast cancer in Shanxi province of China from 2007 to 2016

This study aims to understand the clinical features, treatment, and prognosis of patients with male breast cancer (MBC) in Shanxi province of China from 2007 to 2016. Data for 77 patients with MBC were collected for analysis. Immunohistochemistry, pathological results, and other data such as demographic characteristics (age, marital status, smoking history, drinking history, and family history of cancer) as well as clinical data were investigated by retrieving information from the patients' medical records. A total of 12,404 patients were diagnosed with breast cancer between 2007 and 2016, and 77 were patients with MBC among them. The median diagnosis age of patients with MBC was 62 years (range, 24-84 years). The most common complaint was a painless lump in the breast, accounting for 68.8% of the patients, and the main pathological type in MBC was infiltrating ductal carcinoma (66.2%). In terms of hormone receptors, 80.5% (62/77) of patients with MBC were estrogen receptor positive, 75.3% (58/77) of patients were progesterone receptor positive, and only 6.5% (5/77) of patients were HER2 overexpressing. The multivariant Cox proportional hazards regression analysis showed that M stage is an independent prognostic factor (p=0.018, HR=18.791, 95% CI 1.663 to 212.6). The epidemiological and clinical features of Chinese MBC are similar to that of other countries. As the Chinese public have limited knowledge of MBC, it is necessary to increase awareness among them about it. Further research with a large sample size is required for better understanding of the risks associated with MBC.

Influence of Age on the Clinical Outcome of Breast Cancer for Men and the Development of Second Primary Cancers

BACKGROUND

Low incidence of breast cancer in men (BCM) (< 1% of all breast cancers) has led to a paucity of outcome data. This study evaluated the impact of age on BCM outcomes.

METHODS

For this study, BCM patients treated between 2000 and 2011 were stratified by age (≤ 65 or > 65 years). Kaplan-Meier methods were used to compare overall survival (OS) and breast cancer-specific survival (BCSS). Competing-risk methods analyzed time to second primary cancers (SPCs), with any-cause death treated as a competing risk.

RESULTS

The study identified 152 BCM patients with a median age of 64 years (range 19-96 years). The median body mass index (BMI) was 28 kg/m². Men age 65 years or younger (n = 78, 51%) were more overweight/obese than men older than 65 years (n = 74, 49%) (89% vs 74%, respectively; P = 0.008). Both groups had similar nodal metastases rates (P = 0.4), estrogen receptor positivity (P = 1), and human epidermal growth factor receptor 2 (HER2)neu overexpression (P = 0.6). Men 65 years of age or younger were more likely to receive chemotherapy (P = 0.002). The median follow-up period was 5.8 years (range 0.1-14.4 years). The 5-year OS was 86% (95% confidence interval [CI] 80-93%), whereas the 5-year BCSS was 95% (95% CI 91-99%). The BCM patients 65 years of age and younger had better OS (P = 0.003) but not BCSS (P = 0.8). The 5-year cumulative incidence of SPC was 8.4% (95% CI 3.4-13.4%). The prior SPC rate was higher for men older than 65 years (n = 20, 31%) than for those age 65 years or younger (n = 7, 11%) (P = 0.008). This did not account for differences in life years at risk. No difference was observed in SPC cumulative incidence stratified by age (P = 0.3).

CONCLUSIONS

Men 65 years of age or younger received more chemotherapy and had improved OS, but not BCSS, compared with men older than 65 years. For all BCM, SPC is a risk, and appropriate screening may be warranted.

Favorable Long-Term Outcome in Male Breast Cancer

Objective

Male breast cancer (MBC) is a rare type of cancer in the breast cancer series and in the male population. Data is usually extrapolated from female breast cancer (FBC) studies. We aim to study the clinicopathological characteristics and outcome of MBC patients at our institution and we aim to emphasize the differences compared with FBC.

Materials and Methods

Between January 1993 and April 2016, 56 male patients who were diagnosed as breast cancer and underwent surgical operation were retrospectively analyzed. Patients were evaluated for demographical characteristics, surgery type, clinicopathological characteristics, adjuvant and neoadjuvant treatments, follow-up time, overall survival (OS), disease free survival (DFS), and disease specific survival (DSS).

Results

The ratio of MBC among all breast cancers at our institution is 1%. The median age was 64 (34-85). Surgical procedures were modified radical mastectomy (MRM) in 41 patients (77%), simple mastectomy in 11 patients (21%), and lumpectomy in 1 patient (2%). Two patients were Stage 0 (4%), 7 were Stage 1 (13%), 12 were Stage 2 (22.6%), and 32 were Stage 3 (60.4%). Molecular subtypes of the invasive tumors were luminal A in 40 (80%), luminal B in 6 (12%), HER-2 type in 1 (2%), and basal-like in 3 (6%). Median follow-up time was 77 (3-287) months. 5-year and 10-year OS, DFS, and DSS rates were 80.7%, 96%, 95.6% and 71.6%, 81.9%, 91.7% respectively.

Conclusion

MBC presents different clinicopathological and prognostic factors when compared to FBC. Our survival rates are higher than the average presented in available literature. Because of the high rate of hormone receptor positivity, hormonal therapy is the mainstay for the treatment of estrogen receptor (ER)+ male breast cancer.

Survival analysis for male ductal and lobular breast cancer patients with different stages

AIM

We aimed to investigate risk factors and current treatment effects in male breast cancer patients.

METHODS

Kaplan-Meier plot, log-rank test, COX model, nomograms and propensity score matching were used.

RESULTS

Among stage I-III patients, surgery was associated with better prognosis. In subgroup analysis, performing surgery and no radiation or chemotherapy led to worse prognosis in research group. Among stage IV patients, chemotherapy correlated with better prognosis and radiation led to better breast cancer-specific survival. In addition, brain and liver metastasis correlated with worse prognosis; and lung correlated with worse breast cancer-specific survival.

CONCLUSION

For stage I-III patients, surgery and chemotherapy were recommended. And not applying radiation or chemotherapy could be carefully considered for ER(+) HER-2(-) patients. For stage IV patients, chemotherapy and radiation were commended.

Survival Comparisons Between Early Male and Female Breast Cancer Patients

We aimed to compare the overall survival (OS) and standardized mortality rate (SMR) of the male breast cancer (MBC) with female breast cancer (FBC) after propensity score matching. Based on the Surveillance, Epidemiology, and End Results (SEER), the early breast cancer patients (T1-2N0-2M0) were extracted from 1998-2007. This study included 1,111 and 2,151 patients with early MBC and FBC, respectively, whose clinicopathological characteristics were well balanced. At a mean follow-up time of 97 months, 10-year OS rate was 58.3% in the MBC group and 68.7% in the FBC (log-rank test, P < 0.001; hazard ratio (HR) = 1.45, 95% confidence interval (CI) = 1.29 to 1.64). Adjusted HR for OS between MBC and FBC were revealed from propensity score matched-multivariable Cox proportional hazards models (HR = 1.53, 95% CI = 1.35 to 1.73). Similar adjusted SMRs between MBC and FBC ((SMR = 1.98, 95% CI = 1.83,2.14) for FBC and (SMR = 2.07, 95% CI = 1.88-2.28) for MBC) were observed. The nomogram was constructed for FBC, and predicted probabilities were generally good (C-index = 0.71), whose area under curve is higher than TNM stage classification (0.74 vs 0.62). OS was significantly decreased among early MBC patients compared with FBC, but similar SMRs and its trends by age groups were observed between MBC and FBC except for young patients.

The 21-Gene Recurrence Score in Male Breast Cancer

BACKGROUND

Given the limited data, systemic treatment of male breast cancer has been extrapolated from female patients. The 21-gene recurrence score (RS) assay estimates the risk of distant recurrence and chemotherapy benefit in early-stage, ER+/HER2- female breast cancer. We assessed the association between RS and type of treatment in male breast cancer.

METHODS

We identified male patients with ER+/HER2- breast cancer and available RS results treated at our institution in 2006-2016. We collected data on clinicopathologic features, treatment, and outcome. The Institutional Review Board approved the study.

RESULTS

The study cohort consists of 38 male breast cancer patients with a median age of 70 years. Median tumor size was 1.6 cm, and 81.6% (31) were node-negative. RS was low (≤ 17) in 26 (68.4%) cases, intermediate (18-30) in 9 (23.7%) cases, and high (≥ 31) in 3 (7.9%) cases, comparable to that in female patients at our institution. All patients underwent total mastectomy, and one received radiotherapy. Thirty-four (89.5%) patients received adjuvant endocrine therapy, mostly tamoxifen (81.6%; 31). Five (13.2%) patients with intermediate or high RS were treated with adjuvant chemotherapy. No locoregional recurrence was observed, and one patient developed distant recurrence (median follow-up 34 months).

CONCLUSIONS

The RS distribution in male breast cancers was similar to that in females treated at our institution. With limited follow-up, patients with low RS were spared chemotherapy and did not develop recurrence. Our results suggest that the RS may have a clinical utility in male breast cancer patients.

The Hippo transducers TAZ/YAP and their target CTGF in male breast cancer

Male breast cancer (MBC) is a rare disease and its biology is poorly understood. Deregulated Hippo pathway promotes oncogenic functions in female breast cancer. We herein investigated the expression of the Hippo transducers TAZ/YAP and their target CTGF in MBC. Tissue microarrays containing samples from 255 MBC patients were immunostained for TAZ, YAP and CTGF. One hundred and twenty-nine patients were considered eligible. The Pearson's Chi-squared test of independence was used to test the association between categorical variables. The correlation between TAZ, YAP and CTGF was assessed with the Pearson's correlation coefficient. The Kaplan-Meier method and the log-rank test were used for estimating and comparing survival curves. Cox proportional regression models were built to identify variables impacting overall survival. Statistical tests were two-sided. Tumors were considered to harbor active TAZ/YAP-driven gene transcription when they co-expressed TAZ, or YAP, and CTGF. Patients whose tumors had the TAZ/CTGF and YAP/CTGF phenotypes experienced shorter overall survival compared with their negative counterparts (log rank p = 0.036 for both). TAZ/CTGF and YAP/CTGF tumors were associated with decreased survival in patients with invasive ductal carcinomas, G3 tumors, hormone receptor-positive tumors, and tumors with elevated Ki-67. Multivariate analyses confirmed that the TAZ/CTGF and YAP/CTGF phenotypes are independent predictors of survival (HR 2.03, 95% CI: 1.06-3.90, p = 0.033; and HR 2.00, 95% CI: 1.04-3.84, p = 0.037 respectively). Comparable results were obtained when excluding uncommon histotypes (TAZ/CTGF: HR 2.34, 95% CI: 1.16-4.73, p = 0.018. YAP/CTGF. HR 2.36, 95% CI: 1.17-4.77, p = 0.017). Overall, the TAZ/YAP-driven oncogenic program may be active in MBC, conferring poorer survival.

Treatment Outcomes and Prognostic Factors in Male Patients With Stage IV Breast Cancer: A Population-based Study

PURPOSE

Male breast cancer (MBC) represents < 1% of breast cancer patients, and limited data exists regarding metastatic MBC. To better characterize this patient subset, we performed a population-based study examining prognostic factors among patients with stage IV MBC.

METHODS

Patients with stage IV MBC diagnosed between 1988 and 2012 were selected from the Surveillance, Epidemiology, and End Results database. Prognostic factors for overall survival (OS) and cause-specific survival (CSS) were evaluated.

RESULTS

Overall, 394 patients had metastatic disease meeting inclusion criteria. The median follow-up was 21 months. The 5-year OS and CSS rates were 21.1% and 38.3%, respectively. Of those with known progesterone receptor (PR) status, 52% were PR-positive, which was associated with better OS (P < .001) and CSS (P = .003). Overall, 197 patients (50%) received surgery for the primary tumor, and 197 (50%) did not. Patients undergoing surgery had longer median CSS than those who did not (36 vs. 21 months; P < .001). Additional factors that correlated with prolonged OS and CSS were smaller tumor size (≤ 2 cm; P < .05) and younger age (≤ 65 years; P < .05). In multivariate analysis, smaller tumor size, PR-positivity, younger age, and resection of the primary tumor were associated with longer OS and CSS (P < .05).

CONCLUSIONS

Although stage IV MBC has poor OS and CSS, patients with PR-positive disease, younger age (≤ 65 years), tumor size ≤ 2 cm, or who undergo surgery of the primary tumor have better OS and CSS. This is the largest study of stage IV MBC to date, and these findings address some of the questions regarding this rare presentation of breast cancer.

Epidemiology and survival outcome of breast cancer in a nationwide study

Breast cancer is among the most prevalent cancers in Taiwan. The National Health Insurance database was used to identify patients with breast cancer and estimate the yearly prevalence and incidence of breast cancer between 1997 and 2013. Joinpoint regression analysis was used for the annual percentage change of incidence, prevalence, and survival outcome. Among 12,181,919 female beneficiaries in 2013, the prevalence was 834.37 per 100,000 persons (95% confidence interval, 829.28–839.45) and the incidence was 93.00 per 100,000 person-year (95% confidence interval, 91.27–94.73). The average annual percentage change of the age-standardized breast cancer incidence was 3.5 per 100,000 person-years (3.1–3.8; P < 0.05), suggesting an increase in breast cancer incidence over the study period. The 5-year mortality rate was 4.5% in 1997 and 4.4% in 2008. The 5-year mortality rate among patients with Charlson comorbidity index > 1 was 39.1% (19.2%–59.1%) in 1997 and 21.1% (15.7%-32.0%) in 2008, with an annual percentage change of –0.8 (–1.3 to 2.9), suggesting that the mortality rate was gradually decreasing in patients with comorbidities. In conclusion, 1 in 120 women in Taiwan has breast cancer and the incidence is rising, while the annual percentage change of breast cancer prevalence is decreasing. The mortality rate of breast cancer was essentially stable, but the 1-year, 2-year, and 5-year mortality rates in people with Charlson comorbidity index > 1 were declined.

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.

A review of estrogen receptor/androgen receptor genomics in male breast cancer

Male breast cancer is a rare disease, of which little is known. In contrast to female breast cancer, the very vast majority of all cases are positive for estrogen receptor alpha (ERα), implicating the function of this steroid hormone receptor in tumor development and progression. Consequently, adjuvant treatment of male breast cancer revolves around inhibition of ERα. In addition, the androgen receptor (AR) gradually receives more attention as a relevant novel target in breast cancer treatment. Importantly, the rationale of treatment decision making is strongly based on parallels with female breast cancer. Yet, prognostic indicators are not necessarily the same in breast cancer between both genders, complicating translatability of knowledge developed in female breast cancer toward male patients. Even though ERα and AR are expressed both in female and male disease, are the genomic functions of both steroid hormone receptors conserved between genders? Recent studies have reported on mutational and epigenetic similarities and differences between male and female breast cancer, further suggesting that some features are strongly conserved between the two diseases, whereas others are not. This review critically discusses the recent developments in the study of male breast cancer in relation to ERα and AR action and highlights the potential future studies to further elucidate the genomic regulation of this rare disease.

Male Breast Cancer

Objectives

A clinicopathologic study with an emphasis on tumor immunohistochemical profile is presented.

Methods

Sixty-one cases of male invasive breast cancers were studied. Median age of the cohort was 65 years.

Results

Ninety-seven percent were estrogen receptor positive+ and 10% human epidermal growth factor receptor 2 positive. The individual diagnostic marker positivity was 98% for GATA-binding protein 3, 95% for androgen receptor, 90% for progesterone receptor, 88% for deleted in pancreatic cancer 4, 75% for gross cystic disease fluid protein 15, 72% for cytokeratin 7, 55% for mammaglobin, and 15% for vimentin and Wilms tumor protein 1. Caudal type homeobox 2 protein, cytokeratin 20, Napsin A, paired box gene 8, prostate-specific antigen, thyroid transcription factor 1, and uroplakin II were negative in all cases. Survival analyses showed tumor stage, receptor status, and Nottingham prognostic index to be prognostic. The overall survival was 70%, but the breast cancer–specific survival was 92% (mean follow-up, 59 months); 33% developed second malignancy. The immunohistochemistry profile was similar to female breast cancers.

Conclusions

The second malignancies in this cohort affected overall survival and suggest the possibility of other germline mutations in addition to BRCA2 in male patients with breast cancer.

Locoregional treatment and overall survival of men with T1a,b,cN0M0 breast cancer: A population-based study

BACKGROUND

Male breast cancer (MaBC) is an understudied disease; information about locoregional treatment and outcomes in patients with early stage is unknown. We aimed to analyse patient characteristics, locoregional treatment and overall survival (OS) of T1a,b,cN0M0 male breast cancer.

METHODS

We evaluated men with T1a,b,cN0M0 breast cancer reported to Surveillance, Epidemiology, and End Results program from 1988 to 2012. Univariate and multivariate analyses were performed to determine the effect of each variable on OS.

RESULTS

We included 1263 patients. Median age was 66 years (range 27-103). Median follow-up was 62 months (range 1-294). OS at 5 and 10 years were 85.1% and 66.5%, respectively. Distribution according to tumour sub-stage was: T1a 6.5%, T1b 20.7% and T1c 72.8%. Mastectomy was performed in >74% of patients of each tumour size group and overall 44.1% had >5 lymph nodes examined (LNE). Univariate analysis showed that patients with T1c, no surgery and 0 LNE had worse prognosis. In multivariate analysis, older age (hazard ratio [HR] 11.09), grade 3/4 tumours (HR 1.7), no surgery (HR 3.3), 0 LNE (HR 5.1) and unmarried patients (HR 1.7) had significantly shorter OS. There were no differences in OS between breast conservation versus mastectomy and 1-5 LNE versus > 5 LNE.

CONCLUSION

Men with early breast cancer have a favourable OS. However, older age, higher grade, no breast surgery, no LNE and unmarried status emerged as poor prognostic characteristics. Efforts to decrease the high rates of mastectomy and extensive LNE should be taken given similar OS observed with breast conservation and 1-5 LNE, respectively.

Metastatic Breast Carcinoma to the Prostate Gland

Cancer of the male breast is an uncommon event with metastases to the breast occurring even less frequently. Prostate carcinoma has been reported as the most frequent primary to metastasize to the breast; however, the reverse has not been previously reported. Herein, we present, for the first time, a case of breast carcinoma metastasizing to the prostate gland. Prostate needle core biopsy revealed infiltrative nests of neoplastic epithelioid cells, demonstrated by immunohistochemistry (IHC) to be positive for GATA3 and ER and negative for PSA and P501S. A prostate cocktail by IHC study demonstrated lack of basal cells (p63 and CK903) and no expression of P501S. The patient's previous breast needle core biopsy showed strong ER positivity and negative staining for PR and HER2. Similar to the prostate, the breast was negative for CK5/6, p63, and p40. This case demonstrates the importance of considering a broad differential diagnosis and comparing histology and IHC to prior known malignancies in the setting of atypical presentation or rare tumors.