Poorer Survival of Male Breast Cancer Compared with Female Breast Cancer Patients May Be Due to Biological Differences

Abstract

Objective: The objective of the study was to compare disease-free survival and overall survival in a group of matched males and females with breast cancer, and to analyze possible treatment-and gender-related differences. Methods: We retrospectively analyzed the data of 150 operable male breast cancer patients treated in our hospital from December 1980 to June 2012. Each male breast cancer patient recorded in the database was matched with two female breast cancer patients of equal stage. Prognosis in terms of disease-free survival and overall survival was evaluated. Results: The mean age at diagnosis was 58.6 + 9.7 years for males and 57.2 + 10.3 years for females. The median follow-up was 69 months for males and 81 months for females. Significant differences were identified for tumor location, hormone receptor status, molecular subtypes and hormone therapy between the two groups. Monofactorial analysis demonstrated that tumor size, lymph node state, American Joint Committee on Cancer stage, molecular subtypes and adjuvant chemotherapy treatment were prognostic factors in male breast cancer patients. The 5-and 10-year disease-free survival rates were 65.6 and 40.1% for males, and 74.9 and 51.5% for females, respectively. The 5-and 10-year overall survival rates were 72.9 and 53.9% for males, and 83.2 and 68.5% for females, respectively. There was significantly difference in disease-free survival and overall survival between the two matched groups (P ¼ 0.002). Conclusions: Male breast cancer patients had inferior outcome despite of equal stage in comparison with matched female breast cancer patients, which demonstrates that biological differences may contribute to the worse prognosis.

A retrospective analysis of survival and prognostic factors of male breast cancer from a single center

“…HR status did not significantly affect OS in our cohort, which concords with other reports where HR positivity was more highly expressed than in our patients [2,3,15]. Giordano and coworkers reported a 5.7% negative estrogen receptor status in their cohort, with a 5-year survival of 64%.…”

“…Prognostic factors for MBC are mostly studied in retrospective investigations with small samples. Men with breast cancer reportedly have poorer outcomes than matched women patients, even at the same disease stages, which might be because of variations in tumor biology between male and female patients [3]. Ethnic differences might also affect the prognosis of MBC [4].…”

Patterns of recurrence and treatment in male breast cancer: A clue to prognosis?

“…After controlling for important prognostic factors, we described a worse survival to MBC patients that are similar to other studies, present however, a lower 5‐year overall survival (65.2%) compared to some authors that reported >80% . This could be probably explained by the selection of our population that only contains patients that recurred and because of that have a poor prognosis.…”

“…Male breast cancer (MBC) is a rare disease, accounting for <1% of all breast cancer cases . Recently and due to the increase in its incidence, some studies were published suggesting a worst outcome for male compared to female breast cancer (FBC) patients, justified by: comorbid conditions and delay in the diagnosis in male patients, different age and stage at diagnosis or even differences in tumors biology …”

Breast cancer in male-to-female (MtF) transgender patients: is hormone receptor negativity a feature?

“…These biological differences could potentially impact on clinical prognosis. A recent study by Chen et al 18 stated that male breast cancers had poorer survival outcomes when compared to female breast cancers, which may be attributed to their biological differences.…”