Male breast cancer: 20-year survival data for post-mastectomy radiotherapy

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.

Treatment of male breast cancer: meta-analysis of real-world evidence

BACKGROUND

Breast cancer is rare in men and managed by extrapolating from breast cancer in women. The clinicopathological features of male breast cancer, however, differ from those of female breast cancer. Because clinical trials are rare, the synthesis of real-world data is one method of integrating sufficient evidence on the optimal treatment for this patient population.

METHODS

PubMed, Embase, and Cochrane Library databases were searched. Clinical studies were included if they evaluated the treatments of interest in male breast cancer; these evaluations included breast-conserving surgery (BCS) versus mastectomy, postmastectomy radiation therapy versus no radiation, the accuracy of sentinel lymph node biopsy (SLNB), and a comparison of various endocrine therapies.

RESULTS

Forty studies were retrieved. The pooled estimate of overall survival (OS) revealed no difference between BCS and mastectomy groups. Postmastectomy radiation to the chest wall significantly increased OS relative to no postmastectomy radiation (hazard ratio (HR) 0.67, 95 per cent confidence interval 0.54 to 0.84). The pooled estimates of identification and false-negative rates of SLNB were 97.4 and 7.4 per cent respectively. Tamoxifen treatment was associated with significantly increased OS compared with no tamoxifen intake (HR 0.62, 0.41 to 0.95).

CONCLUSION

Identification and false-negative rates for SLNB were comparable to those in female breast cancer. Breast-conserving surgery can be effective and safe; postmastectomy radiation to the chest wall and 5-year tamoxifen treatment improves survival.

Optimizing utilization and indications for adjuvant radiation in male breast cancer

Due to its rarity, there is a dearth of prospective data on optimal therapeutic strategies in male breast cancer (MBC). Treatment recommendations are mostly extrapolated from evidence in female breast cancer (FBC). Data show that MBC has unique clinical and biological characteristics distinct from FBC. Evidence from retrospective studies suggests that effective therapeutic interventions are often underutilized in MBC and this can compromise outcomes. Population based studies contribute significantly towards the understanding of rare cancers. Multiple studies have demonstrated that adjuvant radiation is associated with improved local control and survival in high risk subgroups of MBC. Multi-center consortia studies contribute significantly towards generating prospective data and optimizing diagnostic and therapeutic strategies in these rare cancers. Enhancing the implementation of treatment recommendations and minimizing disparities in access to care will lead to improved outcomes.

Adjuvant Radiation Therapy for Male Breast Cancer-A Rare Indication?

Due to its rarity, there are no randomized trials investigating the outcome of adjuvant radiotherapy in MBC. This study reports on patient and tumor characteristics of 41 consecutive MBC patients treated between 1990 and 2018 and on clinical outcomes after surgical resection of tumors and adjuvant radiotherapy of the chest wall or breast. Local control (LC), locoregional control (LRC), overall survival (OS), disease-free survival (DFS), and toxicity were evaluated. After a median follow-up of 80 months (95% CI: 14.6-213.8 months) there was only one recurrence, in a patient's locoregional lymph nodes 17 months after start of radiotherapy, resulting in an LC rate of 100% at 5 years and a 5-year LRC rate of 97.4% (standard deviation (SD): 0.025). Five-year DFS and OS rates were 64.6% (SD: 0.085) and 57.2% (SD: 0.082), respectively. Adjuvant radiotherapy was tolerated well without high-grade (CTCAE grade > II) adverse events. After tumor resection and adjuvant radiotherapy, LC and LRC rates in MBC patients are excellent and comparable to results found for female breast cancer (FBC) patients. However, as patients are often diagnosed with locally advanced, higher-risk tumors, distant recurrences remain the major failure pattern.

Oncotype DX for Comprehensive Treatment in Male Breast Cancer: A Case Report and Literature Review

Male breast cancer (MBC) is uncommon in clinical practice. Using the 21-gene assay to facilitate decision-making on comprehensive treatment of MBC is rarely reported. This study reports the case of a 53-year-old man with left breast cancer. Modified radical mastectomy was performed. Endocrine treatment was chosen for the patient according to the result of the 21-gene assay, a recommended genomic test of breast cancer. The patient remained in good health without evidence of recurrence at 18-month follow-up. This case provides a reference mode for the comprehensive management of early-stage, estrogen receptor–expressing and lymph node–negative MBC patients.

Pharmacological management of male breast cancer

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Impact of Adjuvant Radiation Therapy in Patients With Male Breast Cancer: A Multicenter International Analysis

Purpose

Breast cancer in men accounts for approximately 1% of all breast cancers. Breast cancer trials have routinely excluded men. The aim of this analysis was to determine the effect of different treatment factors, in particular, postoperative radiation therapy (RT) on long-term outcomes.

Methods and Materials

Seventy-one patients with male breast cancer treated in 5 closely cooperating institutions between 2003 and 2019 were analyzed.

Results

Almost all patients (95%) underwent surgical resection. Forty-two patients (59%) received chemotherapy, and 59 (83%) received adjuvant hormonal therapy. Of the 71 patients, 52 (73%) were treated with RT. The rate of recurrence was 20% in the whole cohort, with a locoregional recurrence rate of 3%. In the entire group, the 5-year local control (LC) was 95%, whereas 5-year progression-free survival (PFS) and 5-year overall survival (OS) were 62% and 96%, respectively. There was a lower rate of relapses after adjuvant RT (19% vs 32%, P = .05) without in-field relapse after postoperative RT (0%) versus 10% in patients without RT (P = .02). In the multivariate analysis performed, hormonal therapy administration was found to have a possible significant effect on LC and PFS. Administration of adjuvant RT and stage affect PFS. In patients who received RT, there were no grade 3 or 4 acute toxicities.

Conclusions

Adjuvant RT is an effective and safe treatment for male breast cancer patients with no infield relapses and better PFS. Hormonal therapy administration was found to have a possible effect on LC and PFS.

Current state of surgical management for male breast cancer

Management guidelines for male breast cancer have long been extrapolated from those for female breast cancer, which are based on large, randomised-controlled trials. While there are no randomised-controlled trials for male breast cancer management mainly due to the rarity of the disease, the only type of evidence available comes from retrospective studies, subject to selection biases and small sample sizes. Male breast cancer, while similar to female breast cancer in many respects, has some important differences that can affect management choices. Most cancers are oestrogen and progesterone receptor positive, and usually more advanced at presentation than female breast cancer. This is likely due to less breast parenchyma in male patients and delay to diagnosis. The classical management option for male patients with breast cancer is mastectomy, due to small tumour-to-breast ratio and often central position of the tumour. Breast conserving surgery is still useful in selected cases and has similar outcomes when compared to mastectomies in these patients. For patients with clinically negative lymph nodes, sentinel lymph node biopsy offers the same prognosis as axillary lymph node dissection, but with less associated morbidity. Endocrine therapy is of particular use, due to high levels of receptor positivity. Adjuvant endocrine therapy seems to significantly improve overall survival of male patients with breast cancer and while no prospective evidence exists for neoadjuvant hormonal therapy, there is hope that this is a useful management option as well. Radiotherapy is also useful in an adjuvant setting, particularly when combined with endocrine therapy. Better identification of patients, less delay from presentation to diagnosis and more collaborative efforts are key in improving the management, prognosis and outcomes of patients with male breast cancer.

Pattern of care of adjuvant radiotherapy in male breast cancer patients in clinical practice: an observational study

BACKGROUND AND PURPOSE

Due to the rarity of male breast cancer (male BC), no consensus has been reached regarding the most appropriate curative treatment strategy. The objective of the present observational study was to identify patient and tumor characteristics and assess the role of radiotherapy (RT) in clinical practice.

METHODS

Between 1998 and 2014, data of male BC patients treated at two breast centers were consecutively collected and retrospectively analyzed. Patients were stratified based on the addition of adjuvant RT. Data on overall survival (OS) and local recurrence-free survival (LRFS) were estimated with the Kaplan-Meier method and compared by the log-rank test.

RESULTS

A consecutive cohort of 58 male BC patients was evaluated. Median follow-up was 56 months. Twenty-one patients (36.2%) received adjuvant RT. Overall, patients undergoing postoperative RT were characterized by more high-risk features. Patients receiving postoperative RT had significantly more frequently a high UICC stage (50 vs. 9.7% UICC III, p = 0.018) and positive lymph nodes as compared to patients undergoing surgery alone (65 vs. 34.4% pN+, p = 0.046). Accordingly, there was a higher proportion of patients receiving axillary lymph node dissection in the RT group (71.4 vs. 35.6%). Mastectomy was performed in 31/37 (86.1%) in the surgery group as compared to 14/21 (66.7%) in patients receiving postoperative RT. In addition, RT patients were more likely to receive endocrine therapy (78.9 vs. 39.3%, p = 0.016). Outcome was not significantly different between the groups (5-year LRFS: 89.8 vs. 80.0%, p = 0.471 and 5‑year OS 88.4 vs. 88.9%, p = 0.819).

CONCLUSION

The present observational study evaluated the pattern of care in male BC patients treated in clinical practice. Due to its rarity, randomized clinical trials are unlikely and male BC remains an entity with a poor evidence base. Nevertheless, RT remains a crucial component of the multidisciplinary treatment strategy in male BC.

Male breast carcinoma: radiotherapy contributed to favorable local control in two cases and related literature review

Male breast carcinoma (MBC) is rarely encountered in clinical practice. Due to its paucity, our knowledge of MBC only rely on small or single-institutional studies and sporadic cases. The current guidelines for MBC are extrapolated from its female counterparts Rudlowski (Breast Care (Basel) 3(3):183–189, 2008). Nowadays, MBC is actively studied and viewed as a potentially different entity on the aspects of etiology, biological behavior and prognosis. Thus, special treatment strategy guidelines should be established for MBC. Additionally, advance in the systemic chemotherapy and hormonal therapy also contribute to the local control. The indication of radiotherapy need to be clarified and over-treatment should be avoided. Here we present two cases of MBC in which radiotherapy help to sustain a satisfactory disease free survival. Our cases will provide valuable experience for identifying the role of radiotherapy in MBC.

DEGRO practical guidelines for radiotherapy of breast cancer IV: radiotherapy following mastectomy for invasive breast cancer

BACKGROUND AND PURPOSE

Since the last recommendations from the Breast Cancer Expert Panel of the German Society for Radiation Oncology (DEGRO) in 2008, evidence for the effectiveness of postmastectomy radiotherapy (PMRT) has grown. This growth is based on updates of the national S3 and international guidelines, as well as on new data and meta-analyses. New aspects were considered when updating the DEGRO recommendations.

METHODS

The authors performed a comprehensive survey of the literature. Data from recently published (meta-)analyses, randomized clinical trials and international cancer societies' guidelines yielding new aspects compared to 2008 were reviewed and discussed. New aspects were included in the current guidelines. Specific issues relating to particular PMRT constellations, such as the presence of risk factors (lymphovascular invasion, blood vessel invasion, positive lymph node ratio >20 %, resection margins <3 mm, G3 grading, young age/premenopausal status, extracapsular invasion, negative hormone receptor status, invasive lobular cancer, size >2 cm or a combination of ≥ 2 risk factors) and 1-3 positive lymph nodes are emphasized.

RESULTS

The evidence for improved overall survival and local control following PMRT for T4 tumors, positive resection margins, >3 positive lymph nodes and in T3 N0 patients with risk factors such as lymphovascular invasion, G3 grading, close margins, and young age has increased. Recently identified risk factors such as invasive lobular subtype and negative hormone receptor status were included. For patients with 1-3 positive lymph nodes, the recommendation for PMRT has reached the 1a level of evidence.

CONCLUSION

PMRT is mandatory in patients with T4 tumors and/or positive lymph nodes and/or positive resection margins. PMRT should be strongly considered in patients with T3 N0 tumors and risk factors, particularly when two or more risk factors are present.