Clinical Features of Male Breast Cancer: Experiences from Seven Institutions Over 20 Years.
OBJECTIVE
Breast cancer treatment has progressed significantly over the past 20 years. However, knowledge regarding male breast cancer (MBC) is sparse because of its rarity. This study is an investigation of the clinicopathologic features, treatments, and clinical outcomes of MBC.


METHODS
Clinical records of 59 MBC patients diagnosed during 1995-2014 from seven institutions in Korea were reviewed retrospectively.


RESULTS
Over a 20-year period, MBC patients accounted for 0.98% among total breast cancer patients, and increased every 5 years. The median age of MBC patientswas 66 years (range, 24 to 87 years). Forty-three patients (73%) complained of a palpable breast mass initially. The median symptom duration was 5 months (range, 1 to 36 months). Mastectomy was performed in 96% of the patients. The most frequent histology was infiltrating ductal carcinoma (75%). Ninety-one percent of tumors (38/43) were estrogen receptor-positive, and 28% (11/40) showed epidermal growth factor receptor 2 (HER-2) overexpression. After curative surgery, 42% of patients (19/45) received adjuvant chemotherapy; 77% (27/35) received hormone therapy. Five out of ten patients with HER-2 overexpressing tumors did not receive adjuvant anti-HER-2 therapy, while two out of four patients with HER-2 overexpressing tumors received palliative trastuzumab for recurrent and metastatic disease. Letrozole was used for one patient in the palliative setting. The median overall survival durations were 7.2 years (range, 0.6 to 17.0 years) in patients with localized disease and 2.9 years (range, 0.6 to 4.3 years) in those with recurrent or metastatic disease.


CONCLUSIONS
Anti-HER-2 and hormonal therapy, except tamoxifen, have been underutilized in Korean MBC patients compared to female breast cancer patients. With the development of precision medicine, active treatment with targeted agents should be applied. Further investigation of the unique pathobiology of MBC is clinically warranted.
Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea.
Ji Hyung
JH
Hong
Department of Internal Medicine, Seoul St. Mary's Hospital, Seoul, Korea.
Kyung Sun
KS
Ha
Department of Internal Medicine, Yeouido St. Mary's Hospital, Seoul, Korea.
Yun Hwa
YH
Jung
Department of Internal Medicine, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea.
Hye Sung
HS
Won
Department of Internal Medicine, St. Vincent's Hospital, Suwon, Korea.
Ho Jung
HJ
An
Department of Internal Medicine, Bucheon St. Mary's Hospital, Bucheon, Korea.
Guk Jin
GJ
Lee
Department of Internal Medicine, Seoul St. Mary's Hospital, Seoul, Korea.
Donghoon
D
Kang
Department of Internal Medicine, Daejeon St. Mary's Hospital, Daejeon, Korea.
Ji Chan
JC
Park
Department of Internal Medicine, Seoul St. Mary's Hospital, Seoul, Korea.
Sarah
S
Park
Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea.
Jae Ho
JH
Byun
Department of Surgery, St. Vincent's Hospital, Suwon, Korea.
Young Jin
YJ
Suh
Department of Surgery, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea.
Jeong Soo
JS
Kim
Department of Surgery, Yeouido St. Mary's Hospital, Seoul, Korea.
Woo Chan
WC
Park
Department of Surgery, Seoul St. Mary's Hospital, Seoul, Korea.
Sang Seol
SS
Jung
Department of Surgery, Bucheon St. Mary's Hospital, Bucheon, Korea.
Il Young
IY
Park
Department of Radiation Oncology, Yeouido St. Mary's Hospital, Seoul, Korea.
Su-Mi
SM
Chung
Department of Internal Medicine, Yeouido St. Mary's Hospital, Seoul, Korea.
In Sook
IS
Woo
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018567:Breast Neoplasms, Male / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D005260:Female; D020249:Hormone Replacement Therapy / Q000379:methods; D006801:Humans; D000077289:Letrozole; D008297:Male; D008408:Mastectomy; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000235:genetics / Q000473:pathology*; D009570:Nitriles / Q000008:administration & dosage; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics*; D056910:Republic of Korea; D013629:Tamoxifen / Q000008:administration & dosage; D000068878:Trastuzumab / Q000008:administration & dosage; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage
D000077289:Letrozole; D009570:Nitriles; D018719:Erb-b2 Receptor Tyrosine Kinases; D013629:Tamoxifen; D000068878:Trastuzumab; D014230:Triazoles; C508053:ERBB2 protein, human
Male breast neoplasms; Prognosis; Survival