While in women breast cancer is seen more frequently in the post-menopausal period (mean age 62 years), in men it occurs even later at a mean age of 67 years according to the literature [3
]. The mean age of our study cohort was 57 years which is lower than in other countries. The etiology of male breast cancer is unclear, however, many factors including hormonal imbalance, and genetic, environmental and epidemiologic factors have been associated with the disease [8
]. An imbalance of androgens and estrogens may play an important role; lower testosterone production as found in undescended testes, testicular injury, chronic occupational exposure to heat, orchitis, late puberty, and infertility have been suggested as risk factors [9
]. Moreover, previous chest wall irradiation, alcohol consumption, and benign breast conditions such as nipple discharge, breast cysts, and breast trauma may increase the risk of male breast cancer.
Histopathologic findings in women and men differ due to the fact that the classic lobular structure does not occur in men. As the male breast does not have lobular elements, lobular carcinoma is rare (around 1%) in men [2
]. The most frequent histological type is IDC, accounting for 85–90% [5
]. In our study, IDC was diagnosed in 79.3% of cases, which is slightly less than reported; no case of lobular carcinoma was found.
ER and PR expression is higher in male breast cancer compared to female breast cancer (80 and 60%, respectively) [6
]. In our study, receptor analysis was performed in 58 patients, and expression of ER and PR was similar to that reported in the literature. Moreover, until 2003, we extensively developed detection methods for Her-2 in our hospital. Her-2 was detected in only 24 (27.6%) patients, and less again during the following therapy. Her-2 was not included in the prognostic characteristics analysis because of the limited information regarding Her-2.
Breast cancer in men should be treated with the same strategies as applied in women. Although no consensus has been reached regarding locoregional therapy, the primary therapy is mastectomy with axillary dissection [12
]. In previous studies, radical mastectomy was favored based on the rationale that in men the tumors tend to be in close proximity to the pectoralis major muscle and detected at a more advanced stage compared to women [13
]. Recent studies are in favor of modified radical or simple mastectomy combined with radiation therapy [14
]. In our study, with case data spanning more than 40 years, 39 cases received radical mastectomy, and 48 patients accepted modified radical mastectomy; no difference was observed in survival.
Although adjuvant chemotherapy and hormonal therapy have proven beneficial to a subgroup of female breast cancer patients, the role of adjuvant chemotherapy in male breast cancer is less clear [16
]. However, recent studies reported that adjuvant chemotherapy was beneficial for male breast cancer patients [17
]. A decision regarding adjuvant chemotherapy can usually be made by assessing the risks and benefits in the same manner as in female breast cancer patients [11
]. In our study, 64.4% of the patients received adjuvant chemotherapy, and the most frequently used chemotherapy regimens were CMF, CAF, and TA. There were significant differences in 5-year DFS and 5-year OS between the group with adjuvant chemotherapy and the group without adjuvant chemotherapy. Because of high hormone receptor expression rates in male breast cancer, adjuvant hormone therapy with tamoxifen is theoretically the rational therapeutic strategy and should be considered in men with breast cancer [11
]. In several retrospective studies, tamoxifen increased DFS and OS in male breast cancer patients [17
]. In our 87 cases, 45 patients received hormone therapy, and their DFS and OS ratios were higher than those of the group that did not receive hormone therapy. However, no difference was seen in the 5-year DFS/OS between the 2 groups, which may be due to deficits in adjuvant hormone therapy induced by a lack of attention or persistence during hormone therapy.
Postoperative radiotherapy does achieve local control, but no effects have been observed on survival [21
]. In men treated with mastectomy, adjuvant radiotherapy has been shown to decrease local recurrence. Whether or not radiotherapy is indicated depends on local findings [22
]. Radiotherapy is performed in tumors involving the skin and chest wall. Involvement of the skin and nipples is more frequent in men than in women, which may be related to breast size and proximity of the tumor to these structures [24
]. In our study, 37 (42.5%) patients received postoperative radiotherapy, and no significant difference was seen between the group receiving radiotherapy and that not receiving radiotherapy. The similar survival rates may be seen as an indication of a contribution of radiotherapy to DFS and OS.
Consensus has been reached that larger tumors confer a poor prognosis [8
]. Guinee et al. [24
] in their study comprising 335 cases showed that clinical axillary lymph node involvement as well as clinical tumor size had an influence on prognosis. In our study, univariate analysis of 5-year DFS and OS showed tumor size and lymph node involvement to have a significant effect on survival, and multivariate analysis of 5-year DFS showed tumor size to cause significant differences in survival (table ).
Traditionally, the lifespan of men with breast cancer was thought to be shorter than that of female breast cancer patients [3
]. While some investigators explain this with a more aggressive biologic behavior of male breast cancer, the more common explanation is the rareness of male breast cancer resulting in diagnosis at a more advanced stage and non-standard therapy compared to women with breast carcinoma. However, recent studies report that if male breast cancer patients are matched for prognostic factors such as age and TNM stage, the clinical outcome is similar [26
In conclusion, male breast cancer is an uncommon disease. Our study showed that tumor size, stage, lymph node involvement, adjuvant chemotherapy, and recurrence or metastasis had a significant effect on survival; stage was the most important prognosis factor with regard to both DFS and OS. Public awareness of the disease should be improved and an appropriate system for early detection and adequate treatment strategies implemented. Moreover, men presenting with breast symptoms should be examined in the same manner as women to facilitate early detection and better treatment outcomes.