Implications of Highly Penetrant Genetic Variants on Breast Surgery.

It seems the most probable beneficiaries from the molecular era are those harboring hereditary genetic variants, which are responsible for 5% to 10% of all breast cancer diagnoses. There are several key implications of such variants on clinical practice, from expedited anticipation of primary cancer diagnoses, which can have their risk mitigated by risk reduction surgery, to pragmatism surrounding the management of male breast cancer patients. This communication discusses the implications of highly penetrant (or pathogenic) hereditary variants in contemporary breast surgery practice.

Surgical treatment of male breast cancer metastasis to thoracic spine: A case report.

PURPOSE: We present a rare clinical case of a metastatic spinal tumor in the 7th thoracic spine from male breast cancer (MBC). METHOD: A 62-year-old man was referred as an outpatient, complaining of continuous pain in the back and right flank that began 2 weeks earlier. The patient had no neurologic signs or symptoms but had a medical history of left breast modified radical mastectomy because of MBC. Computed tomography and magnetic resonance imaging showed metastasis in the T7 vertebra and no other metastasis on positron emission tomography/computed tomography or bone scan. Separation surgery was performed with posterior corpectomy of T7 (en bloc excision), followed by stabilization with an expandable titanium cage and pedicle screws. The pathological examination of the excised T7 vertebra confirmed metastatic carcinoma with neuroendocrine differentiation from the breast. Adjuvant chemo-radiotherapy was performed after surgery. RESULTS: The patient had no symptoms at the 21-month follow-up. Radiologic studies showed no evidence of recurrent or metastatic lesions. CONCLUSION: MBC is extremely rare, with fewer cases of spinal metastases. Among these, patients who undergo separation surgery are even rarer. This case shows that radical surgery can be an option for MBC with spine metastasis if indicated.

Aggressive Male Breast Cancer-Clinical and Therapeutic Aspects Correlated with the Histopathological Examination: A Case Report and Literature Review.

Breast cancer is often seen as a disease that occurs in women, but it can also appear in men in a very small percentage, below 1%. Men have a minimal amount of breast tissue compared to women, which has the potential to become malignant in a similar way to women, although much less frequently. A patient presented with advanced local invasion due to the low amount of breast tissue, with the tumor quickly invading the adjacent structures. Histopathological and immunohistochemical examinations have an extremely important role in the pathology of breast cancer. Given that male breast cancer is rare and there are not enough surgeons specializing in breast surgery in our country, there is a lack of experience in the management and early diagnosis of this type of cancer, which will be highlighted in this article.

Evaluation of Male Breast Cancer and the Application of Sentinel Lymph Node Biopsy: A Multicenter Retrospective Study.

Sentinel lymph node biopsy (SLNB) is currently used as a routine treatment for patients with breast cancer. However, it may not be applicable for patients with male breast cancer (MBC), because they have notably different clinicopathological features from those occurring in females. There is a lack of evidence of SLNB application and safe exemption from axillary lymph node dissection (ALND) in patients with MBC. This study aimed to evaluate the application of SLNB to provide information for the standardized treatment of patients with MBC. The MBC patient records from 4 institutions ranging from January 2001 to November 2020 were retrospectively reviewed. There were 220 patients with MBC with a median age of 60 (range 24-88) years and an average tumor size of 2.3 cm (range 0.5 cm-6.5 cm). Sixty-six percent of patients underwent SLNB, and 39% of them showed positive results. A total of 157 patients underwent ALND, while only half of them had positive nodes, causing unnecessary complications. For patients in the clinical early stage, we found that the SLNB showed a noninferiority to the ALND treatment in DFS (P = .18) and OS (P = .055). In conclusion, there are certain obstacles to the broad application of SLNB due to the lower proportion of patients with clinically negative lymph nodes. However, it is undeniable that SLNB can safely and effectively exempt patients with MBC at early stage with clinically negative nodes from ALND to reduce subsequent complications. It is still an ideal criterion for the axillary staging of patients with MBC.

Classifying invasive lobular carcinoma as special type breast cancer may be reducing its treatment success: A comparison of survival among invasive lobular carcinoma, invasive ductal carcinoma, and no-lobular special type breast cancer.

PURPOSE: The literature contains different information about the prognosis of invasive lobular carcinoma of breast cancer (BC). We aimed to address the inconsistency by comparatively examining the clinical features and prognosis of invasive lobular carcinoma patients in our university and to report our experience by dividing our patients into various subgroups. PATIENTS AND METHODS: Records of patients with BC admitted to Trakya University School of Medicine Department of Oncology between July 1999 and December 2021 were reviewed. The patients were divided into three groups (No-Special Type BC, Invasive Lobular Special Type BC, No-Lobular Special Type BC). Patient characteristics, treatment methods and oncological results are presented. Survival curves were generated using the Kaplan-Meier method. Statistical significance of survival among the selected variables was compared by using the log-rank test. RESULTS: The patients in our study consisted of 2142 female and 15 male BC patients. There were 1814 patients with No-Special Type BC, 193 patients with Invasive Lobular Special Type BC, and 150 patients with No-Lobular Special Type BC. The duration of disease-free survival (DFS) was 226.5 months for the No-Special Type BC group, 216.7 months for the No-Lobular Special Type BC group, and 197.2 months for the Invasive Lobular Special Type BC group, whereas the duration of overall survival (OS) was 233.2 months for the No-Special Type BC group, 227.9 for the No-Lobular Special Type BC group, and 209.8 for the Invasive Lobular Special Type BC group. The duration of both DFS and OS was the lowest in the Invasive Lobular Special Type BC group. Multivariate factors that were significant risk factors for OS were Invasive Lobular Special Type BC histopathology (p = .045), T stage, N stage, stage, skin infiltration, positive surgical margins, high histological grade, and mitotic index. Modified radical mastectomy, chemotherapy, radiotherapy and use of tamoxifen and aromatase inhibitors for more than 5 years were significant protective factors for overall survival. CONCLUSION: The histopathological subgroup with the worst prognosis in our study was Invasive Lobular Special Type BC. Duration of DFS and OS were significantly shorter in Invasive Lobular Special Type BC than No-Lobular Special Type BC group. The classification of Invasive Lobular BC under the title of Special Type BC should be reconsidered and a more accurate treatment and follow-up process may be required.

Male Accessory Breast Cancer Successfully Treated With Single-Agent Trastuzumab: A Case Report.

Male accessory breast cancer is an extremely rare tumor. There is no report about its monotherapy and subsequent outcome prior to 2022. The current study presents the case of a 76-year-old male patient with a hard mass in the left axilla. Histopathologic examination of an excisional specimen indicated an adenocarcinoma compatible with breast carcinoma. Immunohistochemical analysis demonstrated that the mass was estrogen receptor (ER) (-), progesterone receptor (PR)(-), and human epidermal growth factor receptor type 2 (HER2) (-). A diagnosis of breast cancer originating from the accessory mammary gland in the axilla was made. Two years following surgery, the patient presented with a pulmonary lesion. Core needle biopsy was performed, and the lesion was found to be ER (-), PR(-), and HER2 (3+). The patient was successfully treated with single-agent trastuzumab. Single-agent trastuzumab could be a reasonable regimen for metastatic accessory breast cancer patients with HER2 overexpression for whom chemotherapy and endocrine therapy are not suitable.

Axillary Lymph Node Dissection is Associated with Improved Survival Among Men with Invasive Breast Cancer and Sentinel Node Metastasis.

BACKGROUND: Male breast cancer (MBC) is rare, and management is extrapolated from trials that enroll only women. It is unclear whether contemporary axillary management based on data from landmark trials in women may also apply to men with breast cancer. This study aimed to compare survival in men with positive sentinel lymph nodes after sentinel lymph node biopsy (SLNB) alone versus complete axillary dissection (ALND). PATIENTS AND METHODS: Using the National Cancer Database, men with clinically node-negative, T1 and T2 breast cancer and 1-2 positive sentinel nodes who underwent SLNB or ALND were identified from 2010 to 2020. Both 1:1 propensity score matching and multivariate regression were used to identify patient and disease variables associated with ALND versus SLNB. Survival between ALND and SLNB were compared using Kaplan-Meier methods. RESULTS: A total of 1203 patients were identified: 61.1% underwent SLNB alone and 38.9% underwent ALND. Treatment in academic centers (36.1 vs. 27.7%; p < 0.0001), 2 positive lymph nodes on SLNB (32.9 vs. 17.3%, p < 0.0001) and receipt or recommendation of chemotherapy (66.5 vs. 52.2%, p < 0.0001) were associated with higher likelihood of ALND. After propensity score matching, ALND was associated with superior survival compared with SLNB (5-year overall survival of 83.8 vs. 76.0%; log-rank p = 0.0104). DISCUSSION: The results of this study suggest that among patients with early-stage MBC with limited sentinel lymph node metastasis, ALND is associated with superior survival compared with SLNB alone. These findings indicate that it may be inappropriate to extrapolate the results of the ACOSOG Z0011 and EORTC AMAROS trials to MBC.

Trends in surgery and survival for T1-T2 male breast cancer: A study from the National Cancer Database.

BACKGROUND: Despite evidence that early-stage male breast cancer (MBC) can be treated the same as in females, we hypothesized that men undergo more extensive surgery. METHODS: Patients with clinical T1-2 breast cancer were identified in the National Cancer Database 2004-2016. Trends in surgery type and overall survival were compared between sexes. RESULTS: Of 9,782 males and 1,078,105 females, most were cN0 with AJCC stage I/II disease. Unilateral mastectomy was most common in men (67.1% vs. 24.1%, p < 0.001) and partial mastectomy in women (64.7% vs. 26.4%, p < 0.001), with no significant change over time. Over 1/3 of men received ALND in 2016. While overall survival was superior in females (HR 0.83, 95% CI 0.73-0.94, p = 0.003), partial mastectomy was associated with a 42% reduction in mortality risk for males (HR 0.58, 95% CI 0.4-0.8, p = 0.003). CONCLUSIONS: De-escalation of surgery could be considered for MBC to improve survival and align with current standards of care.

[Malignant Melanoma of a Male Breast That Was Difficult to Differentiate from Breast Cancer-A Case Report].

INTRODUCTION: Malignant melanoma in the male breast is extremely rare. Here we report a case of malignant melanoma in which a small cystic lesion in the male breast gradually increased during follow-up and was difficult to distinguish from breast cancer. CASE: A 65-year-old male was diagnosed with a tumor in the right breast and was referred to our department for further examination. At 42 years of age, he underwent tumor resection of a malignant melanoma of the abdominal skin. Mammary ultrasonography showed a 0.6 cm cystic mass in his right breast. Eight months later, the right breast mass had increased to 1.4 cm, and a core needle biopsy suggested breast cancer. Total mastectomy with axillary lymph node dissection was performed. HE staining of the resected tumor showed intranuclear inclusion bodies and some large nucleoli. On the basis of various immunostaining methods, malignant melanoma was diagnosed instead of breast cancer. After surgery, adjuvant chemotherapy with molecularly targeted drugs was administered. DISCUSSION: This might have been a case of male breast metastasis of malignant melanoma with very late recurrence.

Erysipelas after surgery for breast cancer: a real-world cohort

Erysipelas is often related to lymphedema, which can occur in up to 60% of cases, with advanced age, radiotherapy, tumor extension, surgical approach, and infections as risk factors. The aim of this study was to present and discuss a series of cases of erysipelas after breast cancer surgery treated in a private mastology clinic over the past ten years. This is a retrospective horizontal cohort study in which we selected all cases of erysipelas after breast cancer surgery from 2009 to 2019. The following were evaluated: number of patients treated with a diagnosis of breast carcinoma with axillary approach, age, surgery performed, adjuvant treatment and treatment of erysipelas, presence of lymphedema, and measurement of circumferences between both arms and associated diseases. A total of 12 cases of breast cancer were treated. In 66.66% of cases, a radical axillary lymphadenectomy was performed, and in 16.66% of cases, only a sentinel lymph node investigation was performed. The average age was 67.6 years. Erysipelas appeared, on average, 43 months after cancer diagnosis. Two deaths were reported due to severe erysipelas leading to sepsis. More studies are still needed on the subject. Of the 12 cases in this study, eight (66.66%) were associated with lymphedema. Only two (16.66%) of the patients in this group who developed erysipelas were not submitted to axillary dissection. The treatment for 50% of the participants in this research was with penicillin G benzathine. There were three relapses, and two patients died during the research period

Gynecomastia and Malignancy: A Case of Male Invasive Ductal Breast Carcinoma Treated with Neoadjuvant Chemotherapy.

BACKGROUND Male breast cancer represents a rare malignancy with identifiable risk factors, including genetics, radiation exposure, liver dysfunction, and concomitant diagnosis of Klinefelter syndrome. Gynecomastia can commonly present in these patients, and despite increased estrogen levels in adipose breast tissue, gynecomastia has not been proven to be a significant risk factor for carcinoma development. Male patients with new-onset breast masses are recommended to undergo diagnostic mammograms and breast ultrasound for further evaluation. Those diagnosed with breast cancer most commonly have invasive ductal carcinoma of the breast, and over half of these patients are found to have estrogen and progesterone receptor (ER/PR) positivity. CASE REPORT In this case report, we present a Black man with gynecomastia and an areolar lesion for a 6-month duration following a traumatic event. He was initially referred to the surgical team for further evaluation, and subsequent imaging and biopsy data revealed ER/PR-positive invasive ductal carcinoma. Multidisciplinary discussions were held, and the patient was arranged to begin neoadjuvant treatment with doxorubicin hydrochloride and cyclophosphamide, followed by treatment with paclitaxel (AC-T) chemotherapy, followed by bilateral mastectomy and adjuvant hormonal therapy. CONCLUSIONS The treatment of male breast cancer has remained relatively like that of female breast cancer, which may be due to the limited data in the treatment of male breast cancer. Thus far, studies involving neoadjuvant chemotherapy of female patients have demonstrated promising responses to expand surgical options for patients and possibly decrease the rates of recurrence. Additional studies are warranted to discern optimal therapy for the male patient population.

First report of bilateral synchronous male accessory breast cancer.

Accessory breast occurs due to the persistence of milk line in the non-thoracic region. Malignant transformation in male accessory breast is very rare, with 16 reports documented across the world. No bilateral synchronous accessory male breast cancer has been reported. We present the first case reported globally of a man in his 70s with a complaint of left axillary lump and chronic rash for 3 years. About 1 year ago, additional reddish rash was detected in the right axilla. Initial skin biopsy from a private hospital confirmed mammary carcinoma with skin invasion. Subsequent left breast mastectomy with left axillary lymph node dissection and right wide excision was performed. Final pathological result was grade 2 invasive ductal carcinoma in the left accessory breast and Paget's disease in the contralateral axilla. Postoperative treatment of adjuvant paclitaxel and trastuzumab was prescribed, which was followed by adjuvant radiation therapy.

Sweat Gland Carcinoma With Neuroendocrine Differentiation of the Areola as a Potential Clinicopathologic Mimicker of Male Breast Carcinoma and Syringocystadenocarcinoma Papilliferum.

ABSTRACT: Sweat gland carcinoma with neuroendocrine differentiation (SCAND) is a newly proposed tumor entity of primary cutaneous apocrine/eccrine adnexal tumor with neuroendocrine differentiation. The histopathologic variations are not yet well known. In this article, we present a case of SCAND mimicking male breast cancer and syringocystadenocarcinoma papilliferum. A 68-year-old man presented with a reddish 12-mm nodule on his left areola. No lymph node or distant metastases were observed. The patient was disease free 1 year and 9 months after the tumor was surgically resected but died of cerebral hemorrhage. Histopathological examination revealed a predominantly intradermal tumor with marked syringotropism, mimicking a component of mammary ductal carcinoma in situ. In addition, another tissue section displayed a cup-shaped papillated tumor with syringocystadenocarcinoma papilliferum-like features, which were also seen because of marked syringotropism. Diffuse immunoexpression of cytokeratin 7, cytokeratin 19, chromogranin A, synaptophysin, INSM1, estrogen receptor, carcinoembryonic antigen, epithelial membrane antigen, and GATA3 was observed in the tumor, but no BRAF immunoexpression was seen. The present case would help us to understand the histopathological variation and differential diagnosis of SCAND. The histopathological diagnosis of male breast cancer or syringocystadenocarcinoma papilliferum should be made by ruling out SCAND.

Male Breast Cancer Patient and Surgeon Experience: The Male WhySurg Study.

BACKGROUND: Little is known about the experience of the male breast cancer patient. Mastectomy is often offered despite evidence that breast-conserving surgery (BCS) provides similar outcomes. METHODS: Two concurrent online surveys were distributed from August to October 2020 via social media to male breast cancer (MBC) patients and by email to American Society of Breast Surgeon members. The MBC patients were asked their opinions about their surgery, and the surgeons were asked to provide surgical recommendations for MBC patients. RESULTS: The survey involved 63 MBC patients with a mean age of 62 years (range, 31-79 years). Five MBC patients (7.9 %) stated that their surgeon recommended BCS, but 54 (85.7 %) of the patients underwent unilateral, and 8 (12.7 %) underwent bilateral mastectomy. Most of the patients (n = 60, 96.8 %) had no reconstruction. One third of the patients (n = 21, 33.3 %) felt somewhat or very uncomfortable with their appearance after surgery. The response rate was 16.5 % for the surgeons. Of the 438 surgeons who answered the survey, 298 (73.3 %) were female, 215 (51.7 %) were fellowship-trained, and 244 (58.9 %) had been practicing for 16 years or longer. More than half of surgeons (n = 259, 59.1 %) routinely offered BCS to eligible men, and 180 (41.3 %) stated they had performed BCS on a man with breast cancer. Whereas 89 (20.8 %) of the surgeons stated that they routinely offer reconstruction to MBC patients, 87 (20.3 %) said they do not offer reconstruction, 96 (22.4 %) said they offer it only if the patient requests it, and 157 (36.6 %) said they never consider it as an option. CONCLUSIONS: The study found discordance between MBC patients' satisfaction with their surgery and surgeon recommendations and experience. These data present an opportunity to optimize the MBC patient experience.

The role of postoperative radiation therapy in stage I-III male breast cancer: A population-based study from the surveillance, epidemiology, and End Results database.

BACKGROUND: This study aimed to investigate the role of postoperative radiation therapy in a large population-based cohort of patients with stage I-III male breast cancer (MaBC). METHODS: Patients with stage I-III breast cancer treated with surgery were selected from the Surveillance, Epidemiology, and End Results cancer database from 2010 to 2015. Multivariate logistic regression identified the predictors of radiation therapy administration. Multivariate Cox regression model was used to evaluate the predictors of survival. RESULTS: We identified 1321 patients. Age, stage, positive regional nodes, surgical procedure, and HER2 status were strong predictors of radiation therapy administration. There was no difference between patients who received radiation therapy and those who did not (P = 0.46); however, after propensity score matching, it was associated with improved OS (P = 0.04). In the multivariate analysis of the unmatched cohort, the factors associated with better OS were administration of radiation therapy and chemotherapy. In the subset analysis of the unmatched cohort, postoperative radiation therapy was associated with improved OS in men undergoing breast-conserving surgery (BCS), with four or more node-positive or larger primary tumours (T3/T4). Furthermore, we found no benefit of radiation therapy, regardless of the type of axillary surgery in mastectomy (MS). In older MaBC patients with T1-2N1 who underwent MS, radiation therapy showed no significant effects, regardless of chemotherapy. CONCLUSION: Postoperative radiation therapy could improve the survival of MaBC patients undergoing BCS, with four or more node-positive or larger primary tumours. Moreover, it should be carefully considered in patients undergoing MS and older T1-2N1 patients.

Postmastectomy Reconstruction in Male Breast Cancer.

Introduction: Less than 1% of all breast cancers are diagnosed in males. In females, postmastectomy breast reconstruction is associated with increased patient satisfaction. However, there is a paucity of literature describing reconstructive options for postmastectomy deformity in the male chest. The purpose of this systematic review was to evaluate postmastectomy reconstruction outcomes in males with breast cancer. Methods: A systematic review was performed in accordance with PRISMA guidelines. Ovid MEDLINE, Embase, Cochrane, and Web of Science were queried for records pertaining to the study question using medical subject heading (MeSH) terms such as "male breast cancer," "mastectomy," and "reconstruction." No limitations were placed on the year of publication, country of origin, or study size. Study characteristics and patient demographics were collected. Primary outcomes of interest included postoperative complications, recurrence rate, and mortality rate. Results: A total of 11 articles examining 29 male patients with breast cancer who underwent postmastectomy reconstruction were included for analysis. Literature was most commonly available in the form of case reports. The average age was 59.6 +/-11.4 years. Reconstruction methods included fat grafting (n = 1, 3.4%), silicone implants (n = 1, 3.4%), and autologous chest wall reconstruction with local flaps (n = 26, 89.7%). Postoperative complications occurred in two patients (6.8%), including partial nipple necrosis (n = 1) and hypertrophic scarring (n = 1). Of the studies reporting patient satisfaction, all patients were pleased with the aesthetic appearance of their chest. Conclusion: This systematic review revealed the limited availability of research regarding postmastectomy chest reconstruction in males with breast cancer. Nevertheless, the evidence available suggests that reconstruction can restore a patient's body image and, thus, should be regularly considered and discussed with male patients. Larger studies are warranted to further shed light on this population.

A systematic literature review of the management, oncological outcomes and psychosocial implications of male breast cancer.

BACKGROUND: Although male breast cancer (MBC) is a rare disease, accounting for <1% of all breast cancers, it has significant oncological, survival and psychosocial implications for patients. The aim of this study is to assess the latest literature in the diagnosis, management, oncological outcomes, and psychosocial impact of MBC. METHODS: A systematic literature review was conducted using the PRISMA guidelines (Moher et al., 2009) [1] to explore the management of MBC, with particular focus on investigative imaging, surgical management, oncological outcomes, survival, genetic screening and psychosocial effects. Electronic databases were searched for randomised control trials, cohort studies and case series involving more than 10 patients. Imaging and surgical techniques, local and distant disease recurrence, survival, genetic screening and psychosocial implications in the setting of MBC were assessed. RESULTS: The search criteria identified 199 articles, of which 59 met the inclusion criteria. This included 39,529 patients, with a mean age of 64.5 years (55-71), and a mean follow-up of 66.3 months (26.2-115). Mastectomy remains the most frequently used surgical technique, with an average of 89.6%. Loco-regional and distant recurrence rate was 10.1% and 21.4% respectively. Disease-free survival (DFS) at 5 and 10 years was 66.8% and 54.5% respectively. Disease-specific survival (DSS) at 5 and 10 years was 87.1% and 67.1% respectively. Overall survival (OS) at 5 and 10 years was 72.7% and 50.7% respectively. Genetic screening was conducted in 38.6% of patients of which 4.8% and 15.8% were found to be BRCA1 and BRCA2 carriers respectively. Psychosocial studies were conducted mainly using questionnaire and interview-based methodology focusing primarily on awareness of breast cancer in men, support available and impact on gender identity. CONCLUSIONS: This review demonstrates that men present with later stage disease with subsequent impact on survival outcomes. There remains a paucity of high-level evidence and prospective studies are required. There is a need for increasing awareness amongst the public and health care professionals in order to improve outcomes and reduce stigma associated with MBC.

A rare tumor of the male breast "angiolipoma" Case report and review of literature.

AIM: Angiolipoma is uncommon lesion in the breast and has clinical importance due to the potential of confusion with malignant breast lesions. To date, there is no defined diagnosis and treatment algorithm for breast angiolipomas. We aim to contribute to the literature for the diagnosis and treatment of angiolipomas with this case report and literature review. CASE REPORT: A 29-year-old male patient presented with a newly emerged palpable mass in the right breast. Physical examination revealed a palpable mass in the lower inner quadrant of the right breast without any presence of skin changes, nipple discharge or palpable axillary lymph nodes. The lesion was found to be 3 cm in diameter and showed minimal vascularization on Doppler Ultrasound examination. Surgical excision of the lesion was performed and the lesion was diagnosed as angiolipoma. CONCLUSION: Angiolipomas of the breast in male are rare pathological entities and must always be considered during differential diagnosis, as it can be confused clinically, radiologically and pathologically with other lesions, especially with malignant lesions KEY WORDS: Angiolipoma, Breast, Male breast lesions.

Effect of Breast Conservation Therapy vs Mastectomy on Overall Survival and Breast Cancer-Specific Survival Among Men With Stage I-II Breast Cancer: Analysis of SEER, 2000-2018.

BACKGROUND: Male breast cancer is a rare malignant tumor, and outcomes of breast conservation therapy (BCT) are currently lacking. METHOD: The retrospective, population-based cohort study included 1369 stage I-II (T1-2 N0-1 M0) male breast cancer patients from the SEER database (2000-2018). The patients were grouped in two groups: BCT group and mastectomy group, according to surgical and radiation therapy. Kaplan-Meier method and univariable Cox proportional hazard analysis were used to compare overall survival (OS) and breast cancer-specific survival (BCSS) between two treatment groups. Propensity score matching (PSM) was performed to balance the confounding factors. RESULTS: Of the 1369 men, 97 (7%) patients received BCT, 1272 (93%) received mastectomy alone. The 5- and 10-year OS rates were 92.3% and 80.7% for BCT group compared with 80.4% and 61.4% for mastectomy group. The 5- and 10-year BCSS rates were 96.5% and 93.9% for patients undergoing BCT, as compared with 93.1% and 84.4% for patients undergoing mastectomy. Compared with mastectomy group, BCT group showed improved OS (hazard ratio [HR], 0.294; 95% CI 0.138-0.623, P = .002) and BCSS (hazard ratio [HR], 0.182; 95% CI 0.040-0.820, P = .027). Of the 791 patients with T1 stage, BCT showed insignificant association with OS (hazard ratio [HR], 0.555; 95% CI 0.207-1.488, P = .242) and BCSS (hazard ratio [HR], 1.217; 95% CI 0.171-8.675, P = .844). CONCLUSION: The results of this cohort study suggest that BCT is at least equivalent to mastectomy in male breast cancer patients. The underlying mechanism of this association needs further research.

Male breast cancer: a Singapore perspective.

INTRODUCTION: Male breast cancer (MBC) is rare, representing <1% of all breast cancers. Treatment recommendations have been extrapolated from trial data of female breast cancer patients. This study aims to report our institutional experience of MBC across a 20 year period, analyse the survival outcome and prognosis of this group against female breast cancer patients treated at the same centre. METHODS: Clinical, histopathological, treatment and survival data of male and female breast cancer patients treated between Jan 1999 and July 2019 at Singapore General Hospital and National Cancer Centre Singapore were identified and analysed. RESULTS: Fifty-seven male patients were identified. The median age at diagnosis was 63 years. Majority had invasive ductal carcinoma (86%) and presented at an early disease stage: 70.2% presented as Tis/T1/T2 and 49.1% had no axillary nodal involvement. 84.2% had a simple mastectomy with either a sentinel lymph node biopsy or axillary clearance. The median follow up was 5.69 years for males and 5.83 years for females. The median survival was 11.86 years for males and 16.3 years for females. At 5 years, overall survival (OS) was 69.9% (52.3-82.1%) and disease free survival (DFS) was 62.9% (44.9-76.5%) for males compared with OS 83.8% (83.21-84.39%) and DFS 74.5% (73.91-75.09%) for females. CONCLUSION: MBC remains understudied. Our institutional data indicates that good long term survival in South-East Asian patients can be achieved with treatment protocols that are similar to female breast cancer. More prospective studies are required.