This assignment delves into male breast cancer, covering its incidence, physiological aspects, treatment options, and the psychosocial impacts it carries. We critically appraise the evidence pointing towards potential causes and pinpoint gaps in current research. Furthermore, we describe the primary presenting features of male breast cancer. Male breast cancer is considered a rare ailment and is not among the top twenty cancers responsible for mortality. In the UK, only one in 840 men will encounter breast cancer, with most cases occurring in individuals over 75. Consequently, the mortality rates for this disease in men are notably low. In 2014, male breast cancer accounted for 75 deaths, as Cancer Research UK (CRUK) reported in 2017.
Additionally, we explore the role of genetic inheritance, with approximately 10% of male breast cancer cases attributed to the inheritance of BRCA1 or BRCA2 genes. Coupled with a family history of first-degree relatives experiencing breast cancer, male carriers of these genes face a moderate risk of developing the condition, as documented by the West of Scotland Cancer Genetics Service (WoSCGS) in 2015 and discussed by Ruddy and Winer in 2013.
The occurrence of breast cancer in men presents a distinct pattern compared to women. Notably, it tends to develop 8-10 years later in men, as observed by Fentiman and colleagues in 2006 and 2009. This unique association of male breast cancer (MBC) with older age introduces a noteworthy consideration; reported mortality attributed to breast cancer, when separated from other age-related comorbidities, may be underestimated.
Furthermore, Spiers and Shaaban (2010) highlight a subtle yet significant point. While breast cancer rates in Western countries appear to be declining, such statistics primarily pertain to female breast cancer. These authors conducted a comparative analysis examining the annual incidence of 350 current MBC diagnoses in the UK, with figures reported in the late 1970s and the beginning of the 21st century. Astonishingly, their findings unveiled a rising rate of MBC incidence in the UK, aligning with observations made in the United States by Stang and Thomssen (2008). This discussion raises a compelling question: why does the incidence of male breast cancer in the UK seem to be on the rise?
For individuals who do not carry BRCA1 or BRCA2 mutations, age emerges as a significant risk factor in the development of MBC, as noted by Cutuli and Fentiman in 2010 and 2009, respectively. Consequently, with the proportion of elderly individuals in the UK steadily increasing, as the Office of National Statistics (ONS) reported in 2015, one could argue that a parallel increase in MBC incidence might be anticipated.
Additionally, Brinton and colleagues (2015) investigated additional risk factors. Their study involving 101 MBC sufferers and 217 controls found that MBC risk was elevated in individuals with higher levels of endogenous oestradiol. Interestingly, no such association was discovered with circulating androgens. This observation is intriguing as the risk of MBC attributed to elevated circulating endogenous oestradiol closely parallels the risk associated with postmenopausal female breast cancer, a finding corroborated by various studies, including Kaaks et al. (2014), Dallal et al. (2014), Falk et al. (2013), and others.
However, it’s essential to note that Brinton et al. (2015) failed to account for certain critical variables that could potentially influence MBC risk, raising concerns about their findings’ reliability. Notably, they omitted controls for known risk factors such as BRCA1/2 status, prior history of gynecomastia, and diagnosis of Klinefelter syndrome.
These notable omissions cast doubt on the robustness of Brinton et al.’s (2015) findings. For instance, individuals with Klinefelter syndrome exhibit an imbalance characterized by higher levels of circulating estrogens compared to androgens, as supported by Weiss and colleagues in 2005. Given that Klinefelter syndrome affects a considerable portion of the male population (1 in 500 males, according to the Eunice Kennedy Shriver National Institute of Child Health and Human Development in 2016), a prevalence higher than that of MBC, it is plausible to argue that the risk factor identified in Brinton et al.’s (2015) study may be more attributed to this condition rather than solely to high circulating oestradiol levels devoid of androgenic influence, as their findings may suggest.
Fentiman (2009) concisely summarizes research that has linked occupational exposure to hydrocarbons or working in hot environments with an increased risk of male breast cancer (MBC). In addition to these factors, several studies have explored the potential connection between the rising Body Mass Index (BMI) observed in Western populations, such as those in the US and UK, and the incidence of MBC.
For instance, Brinton et al. (2008) reported findings suggesting that individuals with a BMI exceeding 30 may face an elevated risk of MBC. However, it’s crucial to acknowledge that this study was based on a relatively small sample size, limiting the statistical power required to substantiate these conclusions firmly.
Another study by Ewertz et al. in 2001, which involved 156 men diagnosed with MBC, failed to identify significant associations between MBC risk and factors like parity and age at first childbirth. Such results are unsurprising considering the exclusively male composition of their study population. Moreover, these authors proposed a potential link between MBC risk and obesity and diabetes. However, it’s important to note that this association contradicts the consensus reached by broader research, which indicates an absence of substantial evidence supporting this connection (Giovannucci et al., 2010).
Furthermore, Ewertz et al. found no consistent pattern in the relationship between cigarette smoking and MBC, a finding that contradicts later studies investigating female breast cancer. These subsequent studies, including those conducted by Dossus et al. (2013), Xue et al. (2011), Luo et al. (2011), and McCarty et al. (2009), challenge the notion of a lack of association between smoking and breast cancer, especially in the female population.
Given these conflicting findings, it remains challenging to definitively pinpoint the reasons behind the apparent increase in MBC incidence. The dearth of high-quality data addressing this question underscores the need for further research. This aligns with Giordano’s (2005) characterization of male breast cancer as an “orphan” disease. Giordano aptly notes that obtaining data from prospective randomized controlled trials is unfeasible due to the rarity of this condition.
While prospective randomized controlled trials are often considered the gold standard in research quality by some funding councils, such as the Medical Research Council (MRC, 2018), this viewpoint is not without controversy. For example, Mårtensson et al. (2016) challenge the linear hierarchy of evidence typically used to assess research quality, as described by Bettany-Saltikov in 2012. These alternative perspectives suggest that research funding councils may need to embrace new concepts and approaches to investigate the causes of MBC and determine the most effective treatment strategies.
MBC often manifests as a painless lump beneath the areola, originating from tumor cells within the mammary ductal tissue (Ngoo et al., 2009; Jamal et al., 2006). Men diagnosed with breast cancer may also encounter symptoms such as nipple retraction, nipple discharge, and alterations in the appearance and texture of the skin around the breast and nipple area (Mayo Clinic, 2015; Giordano, 2005). The classification of breast tumors follows the notation established by the European Society of Medical Oncology (ESMO) (Senkus et al., 2015). According to Macmillan (2018b), approximately 80-90% of MBC cases fall under the category of ductal carcinoma, classified as the molecular subtype ‘luminal A’ by ESMO. As Fan et al. (2006) reported, Luminal A tumors account for 30-70% of both male and female breast cancers. Typically, luminal A tumors demonstrate a more favorable prognosis compared to other molecular subtypes, including Luminal B, triple receptor-negative, and Human Epidermal Growth Factor (HER) type 2 negative tumors (Voduc et al., 2010; Carey et al., 2014; Arvold et al., 2010). It’s noteworthy that HER-positive tumors are responsive to monoclonal antibody therapy (trastuzumab) but are not commonly associated with MBC (Macmillan, 2018c).
The choice of treatment for MBC depends on various factors, including the tumor’s stage, molecular subtype, hormone receptor status determined through histopathology, the patient’s age, overall health, and BRCA 1 or 2 status (Senkus et al., 2015; Macmillan, 2018b). Typically, surgical interventions include either a lumpectomy to remove the tumor along with surrounding tissue or a mastectomy that entails the removal of the entire breast. If the tumor has invaded axillary lymph nodes, these nodes may also be excised. To prevent disease recurrence, treatment options may encompass radiotherapy, chemotherapy, and endocrine therapy involving synthetic hormones like tamoxifen (for estrogen receptor-positive tumors) (Macmillan, 2018d).
The psychosocial implications of MBC constitute another area that has received limited research attention. Men who carry the BRCA 1 or 2 gene and face the risk of passing it on to their offspring may experience heightened anxiety and stigmatization (Strømsvik et al., 2010). France et al. (2000) highlighted comparing men with MBC and women with breast cancer regarding body image issues stemming from mastectomy. This may result in men feeling reluctant to expose their chests or wear clothing that reveals their mastectomy, as noted by France et al. Kipling et al. (2014) and Andrykowski (2011) suggest that physical challenges such as weight gain and diabetes may arise from social isolation that prevents men from engaging in sports, particularly after surgery.
Ruddy and Winer (2013) underscore the divergent coping strategies employed by men with breast cancer compared to their female counterparts. Women are more inclined to seek support, whereas men tend to adopt maladaptive coping mechanisms, including avoidance. Despite the rarity of MBC, support resources are available through organizations such as The Male Breast Cancer Coalition (2018). Men who carry the BRCA 1 or 2 gene and face a 50% chance of passing it on to their daughters should have access to genetic counseling, as stipulated by National Institute for Health and Care Excellence (NICE) guidelines (NICE, 2013).
To sum up, there is a lack of evidence explaining the potential increase in the incidence of male breast cancer, which affects only 1 in 840 men. Consequently, research on MBC remains limited. Men who experience stigmatization due to cancer typically associated with women may grapple with social isolation, leading to psychological and physical challenges. To address the deficiency in evidence, funding bodies should acknowledge the value of alternative research approaches beyond large-sample randomized controlled trials (RCTs) to achieve statistical rigor. Moreover, reducing the stigma associated with MBC may require heightened public awareness that breast cancer can affect both men and women. This awareness-raising effort could have the added benefit of increasing men’s vigilance regarding breast health and early detection, ultimately leading to improved outcomes.