A case of HER2-positive male breast cancer with lung metastases showing a good response to trastuzumab and paclitaxel treatment

Outcomes of the patients with metastatic male breast cancer

BACKGROUND

The goal of this research is to investigate the clinical characteristics and prognosis of men with metastatic breast cancer (mMBC).

METHODS

A retrospective analysis of the data of 28 patients was conducted. Kaplan-Meier and Cox regression analyses were used to assess overall survival (OS) and prognostic variables.

RESULTS

At the time of diagnosis, the median age was 57 years (range 26-86). The most prevalent pathological subtype was invasive ductal carcinoma (92.6%). HER2 positivity was 21.6% in patients, with estrogen and progesterone receptor positivity at 96.4% and 71.4%, respectively. Bone-75%, lung-39.3%, brain-21.4%, and adrenal gland-10.7% were the most prevalent metastatic sites. Trastuzumab-based chemotherapy was given to six patients. During the study period, 14 patients (or half) died. All patients had a median OS of 42.6 months (range: 21.6-63.7). The OS rates after 1, 3, and 5 years were 95.7%, 54.2%, and 36.6%, respectively. The number of metastatic locations (P = 0.045), brain metastasis (P = 0.033), and a history of regular alcohol intake (P = 0.008) were all shown to be statistically significant factors affecting OS in univariate analysis. However, multivariate analysis did not support the findings. In addition, we discovered that trastuzumab-based therapy and de-novo metastatic disease had no effect on OS for mMBC.

CONCLUSIONS

The data on mMBC is restricted because of its rarity. The prognosis of mMBC was shown to be poor in this investigation. Despite the small number of patients, we discovered that in univariate analysis, having brain metastases, the number of metastatic locations, and a history of alcohol intake may be prognostic factors.

Male Breast Cancer: From Molecular Genetics to Clinical Management

MBC is a rare disease accounting for almost 1% of all cancers in men and less than 1% of breast cancer. Emerging data on the genetic drivers of predisposition for MBC are available and different risk factors have been associated with its pathogenesis. Genetic alterations, such as pathogenetic variants in BRCA1/2 and other moderate-/low-penetrance genes, along with non-genetic risk factors, have been recognized as pathogenic factors for MBC. Preventive and therapeutic implications could be related to the detection of alterations in predisposing genes, especially BRCA1/2, and to the identification of oncogenic drivers different from FBC. However, approved treatments for MBC remain the same as FBC. Cancer genetic counseling has to be considered in the diagnostic work-up of MBC with or without positive oncological family history. Here, we review the literature, reporting recent data about this malignancy with a specific focus on epidemiology, and genetic and non-genetic risk factors. We introduce the perspective of cancer genetic counseling for MBC patients and their healthy at-risk family members, with a focus on different hereditary cancer syndromes.

Management of Male Breast Cancer: The Journey so Far and Future Directions

Male breast cancer is now shown to be a unique entity and should be considered as a distinct disease. Given the relatively smaller number of cases, randomized controlled trials for treatment are extremely limited and majority of practices are derived from female breast cancer studies. This paper reviews available literature on surgical, radiation, and systemic therapies for male breast cancer, and discusses current practice recommendations.

Clinicopathological features and prognosis of male breast cancer

Objective

We aimed to describe the differences in clinicopathological characteristics and overall survival (OS) between male and female breast cancer patients, and to develop a prognostic nomogram to predict survival in patients with male breast cancer (MBC).

Methods

Using the Surveillance, Epidemiology, and End Results database, we compared age, race, histological type, histological grade, tumor size, lymph node status, metastases, estrogen/progesterone receptor (ER/PR) and HER-2 status between male and female patients, and analyzed their relationships with OS. We established a nomogram and produced a calibration curve to observe its predictive effect.

Results

Age, race, T stage, N stage, bone and lung metastases, and histological type and grade differed between male and female patients. OS in male patients was related to age, tumor size, metastatic site, ER/PR status, and histological grade, but not to race or lymph node status. A nomogram was established, which showed good predictive performance for survival in MBC patients (area under the curve = 0.7).

Conclusion

MBC has a worse prognosis than female breast cancer, mainly characterized by late onset age, late staging, high proportion of invasive non-specific histological types, high histological grade, and luminal breast cancer.

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.

Effects of HER2 status on the prognosis of male breast cancer: a population-based study

Objective

This study was designed to analyze the effects of human epidermal growth factor receptor-2 (HER2) status on the prognosis of male breast cancer (MBC).

Methods

The SEER database was used to identify MBC patients diagnosed between 2010 and 2015. Patients were divided into HER2-negative and HER2-positive groups and chi-square test was used to compare the demographics. Propensity score matching (PSM) was used to remove confounding factors. The log-rank test was used to compare the overall survival (OS) and disease-specific survival (DSS) between the two groups. Univariate and multivariate Cox regression analyses were used to evaluate the effects of different variables on the prognosis of MBC patients. Subgroup analysis was conducted by using R software to explore the benefit of OS and DSS in the subgroup of MBC patients.

Results

In the matched cohort, the log-rank test showed that there was a longer OS (P=0.044) in the HER2-negative group, and the 4-year OS rate in HER2-negative patients was significantly improved (P=0.008), but there was no difference in the DSS (P=0.408) and the 4-year DSS rates (P=0.198) between the two groups. Univariate and multivariate Cox regression also showed that the HER2 status did not independently associate with DSS (P=0.444). Subgroup analysis showed that HER2-negative patients experienced a longer OS in the subgroup of tumors 2–4 cm in size, no distant metastasis and who had received radiotherapy, but none of subgroup was found a significant difference in DSS between different HER2 status.

Conclusion

This study identified that HER2 status had a clear influence on OS in patients with MBC, and there was a longer OS and a higher 4-year OS rate in the HER2-negative group. In addition, we observed that HER2 status had no significant effect on DSS in patients with MBC.

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

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

A case of HER2-positive male occult breast carcinoma with skin and lymph node metastases that exhibited complete response to trastuzumab monotherapy

Metastatic male occult HER2‐positive breast cancer can be successfully treated with trastuzumab monotherapy.

Male Breast Cancer: 20 Years Experience of a Tertiary Hospital from the Middle Black Sea Region of Turkey

BACKGROUND

Male breast cancer is a rare neoplasm, and its treatments are based on those of female breast cancer. This study aimed to analyze 20 years of male breast cancer clinical characteristics and treatment results from the Middle Black Sea Region of Turkey.

MATERIALS AND METHODS

A retrospective analysis of 16 male breast cancer patients treated in our tertiary hospital between 1994 and 2014 was performed. Epidemiologic data, tumor characteristics, and treatments were recorded and compared with 466 female breast cancer ((premenopausal; n=230)+(postmenopausal n=236)) patients. The 5-year disease-free and overall survival rates were calculated.

RESULTS

Male breast cancer constituted 0.1% of all malignant neoplasms in both sexes, 0.2% of all malignant neoplasms in males, and 0.7% of all breast cancers. The mean patient age in this study was 59.8±9.5 (39-74) years. The mean time between first symptom and diagnosis was 32.4±5.3 (3-60) months. Histology revealed infiltrative ductal carcinoma in 81.3% of patients. The most common detected molecular subtype was luminal A, in 12 (75%) patients. Estrogen receptor rate (93.8%) in male breast cancer patients was significantly higher than that in female breast cancer (70.8% in all females, p=0.003; 68.2% in postmenopausal females, p=0.002) patients. Most of the tumors (56.3%) were grade 2. Tumor stage was T4 in 50% of males. The majority (56.3%) of the patients were stage III at diagnosis. Surgery, chemotherapy, radiotherapy and endocrine-therapy were applied to 62.5%, 62.5%, 81.2% and 73.3%, respectively. Loco-regional failure did not occur in any of the cases. All recurrences were metastastic. The 5-year disease-free and overall survival rates in male breast cancer patients were 58% and 68%, respectively.

CONCLUSIONS

Tumors found in male breast cancer patients were similar in size to tumors found in females, but they advanced to T4 stage more rapidly because of the lack of breast parenchymal tissues. The rate of estrogen receptor expression tended to be higher in male breast cancer patients than in female breast cancer patients. Metastasis is the most important problem in initially non-metastatic male breast cancer patients.

Clinicopathological and Immunohistochemical Characteristics in Male Breast Cancer: A Retrospective Case Series

BACKGROUND

Due to its rarity, male breast cancer (mBC) remains an inadequately characterized disease, and current evidence for treatment derives from female breast cancer (FBC).

METHODS

We retrospectively analyzed the clinicopathological characteristics, treatment patterns, and outcomes of mBCs treated from 2000 to 2013.

RESULTS

From a total of 97 patients with mBC, 6 (6.2%) with ductal in situ carcinoma were excluded, and 91 patients with invasive carcinoma were analyzed. Median age was 65 years (range: 25-87 years). Estrogen receptors were positive in 88 patients (96.7%), and progesterone receptors were positive in 84 patients (92.3%). HER-2 was overexpressed in 13 of 85 patients (16%). Median follow-up was 51.5 months (range: 0.5-219.3 months). Five-year progression-free survival (PFS) was 50%, whereas overall survival (OS) was 68.1%. Patients with grades 1 and 2 presented 5-year PFS of 71% versus 22.5% for patients with grade 3 disease; 5-year OS was 85.7% for patients with grades 1 and 2 versus 53.3% of patients with grade 3. Ki-67 score >20% and adjuvant chemotherapy were also statistically significant for OS on univariate analyses. Twenty-six of 87 patients (29.8%) experienced recurrent disease and 16 of 91 patients (17.6%) developed a second neoplasia.

CONCLUSION

Male breast cancer shows different biological patterns compared with FBC, with higher positive hormone-receptor status and lower HER-2 overexpression. Grade 3 and Ki-67 >20% were associated with shorter OS.

IMPLICATIONS FOR PRACTICE

There is little evidence that prognostic features established in female breast cancer, such as grading and Ki-67 labeling index, could be applied to male breast cancer as well. This study found that grade 3 was associated with shorter overall survival and a trend for Ki-67 >20%; this could help in choosing the best treatment option in the adjuvant setting. Many questions remain regarding the impact of HER-2 positivity on survival and treatment with adjuvant anti-HER-2 therapy. Regarding metastatic male breast cancer, the results suggest that common regimens of chemo-, endocrine and immunotherapy used in female breast cancer are safe and effective for men. Male breast cancer patients show a higher incidence of second primary tumors, especially prostate and colon cancers and should therefore be carefully monitored.

New approaches in the management of male breast cancer

Male breast cancer (MBC) is a rare condition that accounts for 0.1% of all male cancers. Our current evidence base for treatment is derived from female breast cancer (FBC) patients. Risk factors for MBC include age, genetic predisposition, race, sex hormone exposure, and environmental factors. Most patients present later and with more advanced disease than comparable FBC patients. Tumors are likely to be estrogen receptor and progesterone receptor positive, with the most common histologic type being invasive ductal carcinoma. Triple assessment remains the criterion standard for diagnosis. Primary MBC is mostly managed initially by simple mastectomy, with the option of breast conserving surgery, which carries an increased risk of recurrence. Sentinel node biopsy is recommended as the initial procedure for staging the axilla. Reconstructive surgery focuses on achieving primary skin closure, and radiotherapy largely follows treatment protocols validated in FBC. We recommend chemotherapy for men with more advanced disease, in particular, those with estrogen receptor negative histology. MBC responds well to endocrine therapy, although it is associated with significant adverse effects. Third-generation aromatase inhibitors are promising but raise concerns due to their failure to prevent estrogen synthesis in the testes. Fulvestrant remains unproven as a therapy, and data on trastuzumab is equivocal with HER2 receptor expression and functionality unclear in MBC. In metastatic disease, drug-based hormonal manipulation remains a first-line therapy, followed by systemic chemotherapy for hormone-refractory disease. Prognosis for MBC has improved over the past 30 years, with survival affected by disease staging, histologic classification, and comorbidity.

HER2-positive male breast cancer: an update

Although rare, male breast cancer (MBC) remains a substantial cause for morbidity and mortality in men. Based on age frequency distribution, age-specific incidence rate pattern, and prognostic factor profiles, MBC is considered similar to postmenopausal breast cancer (BC). Compared with female BC (FBC), MBC cases are more often hormonal receptor (estrogen receptor/progesterone receptor [ER/PR]) positive and human epidermal growth factor receptor 2 (HER2) negative. Treatment of MBC patients follows the same indications as female postmenopausal with surgery, systemic therapy, and radiotherapy. To date, ER/PR and HER2 status provides baseline predictive information used in selecting optimal adjuvant/neoadjuvant therapy and in the selection of therapy for recurrent or metastatic disease. HER2 represents a very interesting molecular target and a number of compounds (trastuzumab [Herceptin®; F. Hoffmann-La Roche, Basel, Switzerland] and lapatinib [Tykerb®, GlaxoSmithKline, London, UK]) are currently under clinical evaluation. Particularly, trastuzumab, a monoclonal antibody which selectively binds the extracellular domain of HER2, has become an important therapeutic agent for women with HER2-positive (HER2+) BC. Currently, data regarding the use of trastuzumab in MBC patients is limited and only few case reports exist. In all cases, MBC patients received trastuzumab concomitantly with other drugs and no severe toxicity above grade 3 was observed. However, MBC patients that would be candidate for trastuzumab therapy (ie, HER2+/ER+ or HER2+/ER- MBCs) represent only a very small percentage of MBC cases. This is noteworthy, when taking into account that trastuzumab is an important and expensive component of systemic BC therapy. Since there is no data supporting the fact that response to therapy is different for men or women, we concluded that systemic therapy in MBC should be considered on the same basis as for FBC. Particularly in male patients, trastuzumab should be considered exclusively for advanced disease or high-risk HER2+ early BCs. On the other hand, lapatinib (Tykerb), a novel oral dual tyrosine kinase inhibitor that targets both HER2 and epidermal growth factor receptor, may represent an interesting and promising therapeutic agent for trastuzumab-resistant MBC patients.

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.