Men Breast Cancer (MBC) is uncommon and occurs after the age of 60 years. Among men the prognosis is poor as the cause of a medical condition is discovered at a late stage where infiltrating ductal carcinoma accounts for 70-90% of male breast cancers. The In situ but not invasive carcinoma is exclusively ductal, and it accounts only 7% to 8% of the breast cancer cases in males. It is observed that 50-75% of breast cancer cases are spread to lymph nodes. The etiology of male breast cancer is unknown. An excess risk has been associated with the testicular disorders, obesity, benign breast disease including gynecomastia, Klinefelter syndrome, etc. Preliminary evidence suggests that BRCA2 is a strong cause. The carriers of the males with BRCA2 mutation have an increased lifetime risk of breast cancer with 80-fold in it. It is also known that there is also a risk of breast cancer associated with undescended testes and it is also related to orchiectomy, orchitis, testicular injury, etc., with an increasing number of children the decreasing trend in risk was observed gradually. It is also known that Liver cirrhosis is associated with increased levels of estrogens possibly via high levels of endogenous estrogens.

Keywords: Alcohol, BRCA2, Estrogens, Gynecomastia, Intraoperative, MBC, Mammography, Testicular, Ultrasonography, Smoking

The evidence known is that the analytical epidemiology of male breast cancer is similar with the epidemiology of female breast cancer, with a potential role of factors related to hormonal status. It is also known that the relative hyper estrogeny in men is potentially linked to increased risk of disease. It is also believed that Genetics may also play a role; the high risk is linked to a familial history of breast cancer. There is also a major risk in patients with Klinefelter's syndrome. It is known that these studies are not only carried in Europe and America, they are also carried out in Africa. For example a Stage, estrogen receptor status, treatment and survival of 29 men with breast cancer attending the Breast Clinic was carried out in the Johannesburg Hospital between 1976 and 1985 and were reviewed. Most patients had loco-regionally advanced disease at presentation.

What are causes of male breast malignancy is a common question. Torre et al. [4] and Jemal et al. [3] say that the risk factors associated with the leading causes of cancer death include tobacco use in lung, colorectal, stomach and liver cancer, overweight and obesity and physical inactivity in breast and colorectal cancer and infection in liver, stomach and cervical cancer. So a substantial portion of cancer cases and deaths can be prevented by applying effective prevention measures, such as tobacco control. A meta-analysis of alcohol drinking and cancer risk. Bagnardi et al. [6] suggest that the evidence is provided by the epidemiological literature on the association between alcohol consumption and the risk of 18 neoplasms. They performed a search of the epidemiological literature from 1966 to 2000 using several bibliographic databases. Meta-regression models were fitted considering linear and non-linear effects of alcohol intake. They found that strong trends in alcohol consumption risk were observed for cancers of the oral cavity and pharynx, esophagus and larynx. Less strong direct relations were observed for cancers of the stomach, colon and rectum, liver, breast and ovary. It was seen that these diseases, showed significant increased risks in ethanol intake of 25 g per day. They also demonstrated that there was no either significant or consistent relation for cancers of the pancreas, lung, prostate or bladder. Boffetta and Hashibe [7] put in more details that there is a causal association been established alcohol consumption and cancers of the oral cavity, pharynx, larynx, esophagus, liver, colon, rectum and in women breast; an association is suspected for cancers of the pancreas and lung. There is evidence that suggests that the effect of alcohol is modulated by polymorphisms in genes encoding enzymes for ethanol metabolism. They give the examples like alcohol dehydrogenases, aldehyde dehydrogenases and cytochrome (P450 2E1), folate metabolism and DNA repair. They conclude that the mechanisms by which alcohol consumption exerts its carcinogenic effect have not been fully defined, although possible events include; a genotoxic effect of acetaldehyde, the main metabolite of ethanol, increased estrogen concentration, which is important for breast carcinogenesis and also a role of solvent for tobacco carcinogens. The other types of evidence include production of reactive oxygen species and nitrogen species and changes in folate metabolism. Alcohol consumption is increasing in many countries and is an important cause of cancer worldwide. It is known that in the sub-Sahara regions men’s alcohol consumption is well established but female consumption is also on the rise. More evidence is known by other workers, for example, Castellsagué et al. [8] show that it is not only alcohol consumption, but joint effects of tobacco smoking and alcohol drinking, may lead to Cancer causing. They analyzed data from a series of 5 hospital‐based case‐control studies of squamous‐cell carcinoma of the esophagus conducted in high‐risk areas in South America. A total of 830 case subjects and 1779 control subjects were included in the pooled analysis. All exposure characteristics of amount, duration, cessation and type of alcohol and tobacco consumed were strongly related to esophageal‐cancer risk in both sexes. Women had the same exposure profile as men, but the magnitudes of the associations were lower than were those among men. In their study it was evident that black‐tobacco smoking was associated with a 2‐fold increased risk as compared with the smoking of blond or mixed tobacco and more details showed that Alcohol and tobacco alone were strongly related to the risk of esophageal cancer. Particularly the history of simultaneous exposure to cigarette smoking and alcohol drinking had a strong suggestive effect on risk for cancer. Worse still, it was the evidence that a mixed exposure of heavy alcohol drinking and black‐tobacco smoking identified the group with the highest risk for developing esophageal cancer (odds ratio=107). They concluded that moderate cigarette smoking without drinking and moderate alcohol drinking without smoking had a negligible effect on esophageal-cancer risk. But, simultaneous exposure to the same moderate amounts increased the risk 12 to 19‐fold in men and in women, respectively. There was no specific evidence on the effect of smoking and alcohol on the breast malignancy in men. In Denmark, France, Germany, Italy and Sweden, Guénel et al. [9] investigated the role of alcohol drinking in male breast cancer using data collected in a population-based case. In their study, the cases were 74 histologically verified male breast cancer patients aged 35-70 years. The controls (n=1432) were selected from population registers and frequency-matched to the cases by age group and geographic area. They checked for consistency, so a separate analysis was conducted using as controls the patients with a rare cancer other than male breast recruited simultaneously in the European study (n=519 men). They found that the risk of developing breast cancer in men increased by 16% (95% CI: 7-26%) per 10 g alcohol per day (p<0.001). An odds ratio of 5.89 (95% CI: 2.21-15.69) was observed for alcohol intake greater than 90 g/day, as compared with light consumers (<15 g/day). They concluded that the relative risk of breast cancer in men is comparable to that in women for alcohol intakes below 60 g/day.  

The estimated number of cancer cases and deaths attributable to alcohol drinking in 2002 by the WHO sub region, based on relative risks of cancers of the oral cavity, pharynx, esophagus, liver, colon, rectum, larynx and female breast obtained from recent meta and pooled analyses and data on prevalence of drinkers obtained from the WHO Global Burden of Disease project shows the fact that there is a total of 389,100 cases of cancer. These are attributable to alcohol drinking worldwide, representing 3.6% of all cancers (5.2% in men, 1.7% in women). The corresponding figure for mortality is 232,900 deaths (3.5% of all cancer deaths).

It is known that Men Breast Cancer (MBC) is an uncommon but it is a serious problem in men. Carcinoma of the male breast accounts for 0.8% of all breast cancers. A considerable debate exists concerning the prognosis of breast cancer in male patients compared with that in female patients. Some studies have observed worse prognosis for men; others suggested the higher mortality rates were primarily due to delayed diagnosis. Borgen et al. [10] carried a study of survival time from diagnosis with invasive disease to death resulting from breast cancer of 58 men treated between 1973 and 1989 was compared with survival of 174 women treated between 1976 and 1978 who were matched by stage of disease and age at diagnosis. All patients were treated by mastectomy and axillary dissection. The results showed the following: In tumors which were less than 2 cm in 70% of cases and 55% were free of axillary metastases. The histology of the tumors differed significantly by gender (p<0.05). Significantly more men had estrogen receptor-positive tumors (87%) than did women (55%, p<0.001). Survival at 10 years was similar for male and female patients. Epidemiologic studies of breast cancer in men have provided insights into the pathogenesis and etiology of breast cancer in both sexes. Thomas [11] points out the facts that the incidence and mortality rates of breast cancer among countries and racial and ethnic groups have been observed mainly in women but these problems also occur in men. In women the fact clearly indicates that the causes of these variations are primarily risk factors related to the female. It is known that it occurs in women at the change in the rate of increase at the usual age of menopause; the assumption is that the midlife change in the rate of increase with age in women is due to the reduction in ovarian hormone production at menopause. In men the risk of breast cancer goes on to occurring as age increases. These data conflict with the conventional even in prognosis, the wisdom shows that breast cancer in men carries a worse prognosis than the disease in women. Individual carcinomas from both the male and female breast are histologically indistinguishable, but histologic types of ductal origin occur relatively more frequently in men than in women and those of lobular origin are very uncommon in men, reflecting the absence of lobular structures in the normal male breast. Spatz [12] clarifies more details in that breast cancer occurs at an older age in men than in women, usually it presents as a painless, central breast lump. It is known that male breast cancer is 100 times less common than female breast cancer; however, the prognosis for men is worse than that for women as has been said. This is because of the delay in diagnosis. Men with breast cancer have a high prevalence of metastatic disease at the time of diagnosis. So although Carcinoma of the male breast (MBC) it is an uncommon phenomenon, it is accounting for less than 1% of all malignancies in men. It represents a biologically heterogeneous disorder and its clinical course may vary from indolent and slowly progressive to rapidly metastatic disease. Most of the MBC current knowledge regarding its biology, natural history and treatment strategies has been drawn from its female counterpart. The information regarding the prognostic relevance of new molecular markers is not fully understood.

The scientific study of infectious diseases and their causes of breast cancer also have provided insights into the pathogenesis and etiology in both sexes related to breast cancer. It is histologically not distinguishable that individual carcinomas are types of ductal origin that are observed from both the male and female breast, but these situations are more common in men than women because it is clearly observed that the increase of age in men is a causing the risk of breast cancer.

Between 1983 and 1987,the incident cases (n=227) were diagnosed  and obtained from 10 population-based cancer registries of the surveillance, epidemiology and end results program of the National Cancer Institute. The Controls (n=300) were selected by random digit dialing and from Medicare eligibility lists. The exposure status were defined as ever having been employed in a job which was classified as involving potential exposure to electromagnetic was assigned without knowledge of case/control status. Demers et al. [13] found out the following: An elevated risk was found for any job with exposure (odds ratio (OR)=1.8, 95% confidence interval (CI) 1.0-3.7) and risk was highest among electricians, telephone linemen and electric power workers (OR=6.0, 95% CI=1.7-21) and radio and communications workers (OR=2.9, 95% CI=0.8-10). They found that the risk did not vary with duration of exposed employment. The risk was highest among subjects who were first employed in jobs with exposure before the age of 30 years and who were initially exposed at least 30 years prior to diagnosis. These results were due to the theory that electromagnetic fields may be related to breast cancer in men.

In the US Men account for less than 1% of all cases of breast cancer, estimates for 1995 showed that there were only 1400 (0.76%) of the 183,400 cases of breast cancer in the United States that occurred in men. From the above paragraph we have already discussed that prognosis in men is poor, but it is easy to detect the breast cancer as men have so little breast tissue. Infiltrating ductal carcinoma accounts for most cases (70-90%) of male breast cancers. In situ but not invasive carcinoma is exclusively ductal and accounts for 7% of cases. The spread to lymph nodes are observed in 50-75% of cases. In Zambia we do not have the records.

History is known that the earliest reference to breast cancer that the Edwin Smith Surgical Papyrus from Egypt contents, shows that MBC dates were from 3000 to 2500 years B.C. Despite all this, knowledge relevant to many aspects of the disease in men is still limited. Crichlow [14] adds on the fact that carcinoma of the male breast is a rare neoplasm and comprises only 1% of all breast carcinomas and less than 1.5% of malignant tumors in men. He adds on that the important differences exist between the men and women in clinical presentation and prognosis. Males present at a later age and often after a longer delay. The tendency for ulceration of the overlying epidermis is far greater in men than women. Prognosis appears to be worse overall for men. Palade et al. [15] points out that in 20 years they registered 10 observations of male breast cancer (MBC) represented 1.3% out of 767 patients with breast cancer. Most men with breast cancer present with a mass in the breast, the evaluation of which should include a tissue diagnosis. The adequate local 38 therapy includes total removal of the breast only if the presence of invasive cancer is established.

The difficulty of discovering MBC is that it tends to occur at an older age in men than in women as mentioned above, the problem is that it usually presents itself as a painless, central breast lump. Although male breast cancer is 100 times less common than female breast cancer, the 42 prognoses for men is worse than that for women, probably because of delay in diagnosis. A small share of breast cancer, those cases arising at a young age, causes due to the inheritance of dominant susceptibility genes conferring disease with a high risk. The survival rates for men and women are similar in the stage of age-adjusted to 5 years, but comorbidities in older men lead to worse prognosis. Mammography is the process of using low-energy X-rays to examine the human breast for diagnosis and screening is required for palpable breast masses in men. Block and Muradali [16] point out that mammography has a sensitivity of 92% and specificity of 90% for male breast cancer (n=104). Hsing et al. [17] points out that the etiology of male breast cancer is unknown. Other writers suggest that obesity increases the risk of male breast cancer, possibly through hormonal mechanisms. The risk factors for male breast cancer include history of the family, genes mutations age, radiations of the chest and altered testosterone-estrogen levels (for e.g. due to liver cirrhosis, gonad dysfunction, estrogen use, obesity). Preliminary evidence suggests that BRCA2 is a strong cause. However, it does not confer a substantially elevated risk of ovarian cancer in contrast to BRCA1. Occurrence of male breast cancer, a rare disease, peaks at age 71 years. Familial cases usually have BRCA2 rather than BRCA1 mutations: That is what above is said. Occupational risks include high temperature environments and exhaust fumes, but electromagnetic fields have not been implicated as Demers et al. [13] have found hyper estrogenisation resulting from Klinefelter's, gonadal dysfunction, obesity or excess alcohol, all increase risk as does exposure to radiation, whereas gynaecomastia does not. However, some workers think gynecomastia does lead to MBC. Thomas et al. [18] suggest the following: an increased risk of breast cancer is most strongly associated with undescended testes and is also related to orchiectomy, orchitis, testicular injury, late puberty and infertility; a decreasing trend in risk was observed with an increasing number of children. High blood cholesterol, rapid weight gain, benign breast conditions and hesitancy obesity are the relative risks that estimate the breast cancer in men. About 90% of tumors are estrogen-receptor-positive, among them tamoxifen is a standard adjuvant therapy, but some of the individuals could also benefit causes from chemotherapy technique. In men, an increase in risk of breast cancer has been associated with testicular pathology and dysfunction and a decrease in risk has been related to high fertility, a history of prostate cancer, and exogenous androgens. Whereas, an immunohistochemical analysis shows that the tumors are positive only for progesterone and estrogen receptors more frequently in men rather than women. It is also known that liver cirrhosis is associated with increased levels of estrogens possibly via high levels of endogenous estrogens, which increases the risk of breast cancer in men. Mostly men from United States die from breast cancer rather than from testicular cancer; where 9355 men diagnosed with breast cancer in the United States from 2004 to 2008, there were 1934 deaths, compared with 1758 deaths from the 39,641 cases of testicular cancer. Rosenblatt et al. [19] think that the developing breast cancer were greater in men with relative odds and who developed their mammary neoplasm before the age of 45 with the first-degree relatives than in men with older first degree affected relatives; the risk in men with an affected sister was greater in those under age 60 than in older men. The problem of MBC may also include Occupational risks which include: high temperature environments and exhaust fumes, but electromagnetic fields have not been implicated. Hyper estrogenisation resulting from Klinefelter’s, gonadal dysfunction, etc., also increase risk as it exposure to radiation. However, two observations of gynecomastia have been noted as a possible risk factor for MBC. Other workers feel gynecomastia does not lead to MBC. 

Workers like Weiss et al. [20] say the same but make it clearer. They say that the suspected genetic factors in MBC include AR gene mutations, CYP17 polymorphism, Cowden syndrome and CHEK2. They add on by saying that the epidemiologic risk factors for MBC include disorders relating to hormonal imbalances, such as obesity, testicular disorders (e.g. cryptorchidism, mumps orchitis and orchiectomy) and radiation exposure. They add on that the suspected epidemiologic risk factors include prostate cancer, prostate cancer treatment, gynecomastia, occupational exposures (e.g. electromagnetic fields, polycyclic aromatic hydrocarbons and high temperatures), dietary factors (e.g. meat intake and fruit and vegetable consumption) and alcohol intake. These discussions bring out so many differences and also agreements and disagreements concerning MBC in men.

In the European Institute of Oncology, Gennari et al. [21] performed a study showing data in which p21Waf1 and p27Kip1 proteins were evaluated in a series of male breast cancer patients. Their data also suggested that the immunohistochemical evaluation of p21Waf1 and p27Kip1 expression in male breast carcinomas may be a further useful marker for selecting patients who express functional proteins that can be predictive for the most efficient endocrine response. In searching for more conservative treatment, they introduced in their clinical practice sentinel node biopsy, and if present, the sentinel node biopsy of the internal mammary chain was noted. The potential clinical implications of complete nodal staging were far-reaching and gave them a major new opportunity to stratify male patients with breast cancer for appropriate surgery as well as giving valuable prognostic information. They concluded that MBC has biological differences compared with female breast cancer.

The familial aggregation of breast cancer in males also requires a study. Rosenblatt et al. [19] investigated a population-based case-control study. In their study the cases were ascertained from 10 surveillance, epidemiology, and end results program registries in the United States between 1983 and 1986. Controls were identified by random-digit dialing and from lists of Medicare recipients. In their study, the relative odds of developing breast cancer were similar in men with affected paternal and maternal relatives and in men with affected mothers and sisters. The risk chances of getting cancer in a male increased with the number of affected relatives to the man. They confirmed the fact that the development of breast cancer was greater in men with first-degree relatives who developed their mammary neoplasm before the age of 45 than in men with older first-degree affected relatives; the enhancement of risk in men with an affected sister was greater in those under age 60 than in older men. Easton et al. [22] add on to this familial effect of MBC. They say that Breast cancer is known to have an inherited component, consistent in some families with autosomal dominant inheritance; in such families the disease often occurs in association with ovarian cancer. Previous genetic linkage studies have established that in some such family disease occurrence is linked to markers on chromosome 17q. Their work reports the results of a collaborative linkage study involving 214 breast cancer families, including 57 breast-ovarian cancer families; this represents almost all the known families with 17q linkage data. Their point is that under the genetic model used in the analysis, the most estimate of the proportion of linked breast-ovarian cancer families was 1.0 (lower LOD-1 limit 0.79). In contrast, there was significant evidence of genetic heterogeneity among the families without ovarian cancer, with an estimated 45% being linked. These results suggest that a gene(s) on chromosome 17q accounts for the majority of families in which both early-onset breast cancer and ovarian cancer occur but that other genes predisposing to breast cancer exist. By examining the fit of the linkage data to different penetrance functions, the cumulative risk associated with the 17q gene was estimated.

How do we diagnose MBC? Diagnosis of the breast cancer in men is mainly based on examination with clinical testing, followed by ultrasonography, mammography, etc., whereas, the aspiration cytology makes it possible to confirm the malignancy tumors. The intraoperative pathology examination confirms malignancy with resection biopsy and makes wider excision possible during the same procedure. The Presentation of the tumor is usually a lump or nipple inversion, but is often late, with more than 40% of individuals having stage III or IV disease. Most tumors are ductal type only but in situ only 10% are ductal carcinomas. When survival is adjusted for age at diagnosis and stage of disease, outcomes for male and female patients with breast cancer is similar. Surgery is usually mastectomy with axillary clearance or sentinel node biopsy. Because 90% of tumors are hormonal receptor positive, tamoxifen is the standard adjuvant therapy. Indications for radiotherapy and chemotherapy are similar to female breast cancer. For metastatic disease, hormonal therapy is the main treatment, but chemotherapy can also provide palliation.

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