Results with accelerated partial breast irradiation in terms of estrogen receptor, progesterone receptor, and human growth factor receptor 2 status.
OBJECTIVE
To report our results with accelerated partial breast irradiation (APBI) in terms of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2/neu) status.


METHODS
Between February 2003 and June 2009, 209 women with early-stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions twice daily over 5-7 days. Three patient groups were defined by receptor status: Group 1: ER or PR (+) and HER-2/neu (-) (n = 180), Group 2: ER and PR (-) and HER-2/neu (+) (n = 10), and Group 3: ER, PR, and HER-2/neu (-) (triple negative breast cancer, n = 19). Median follow-up was 22 months.


RESULTS
Group 3 patients had significantly higher Scarff-Bloom-Richardson scores (p < 0.001). The 3-year ipsilateral breast tumor control rates for Groups 1, 2, and 3 were 99%, 100%, and 100%, respectively (p = 0.15). Group 3 patients tended to experience relapse in distant sites earlier than did non-Group 3 patients. The 3-year relapse-free survival rates for Groups 1, 2, and 3 were 100%, 100%, and 81%, respectively (p = 0.046). The 3-year cause-specific and overall survival rates for Groups 1, 2, and 3 were 100%, 100%, and 89%, respectively (p = 0.002).


CONCLUSIONS
Triple negative breast cancer patients typically have high-grade tumors with significantly worse relapse-free, cause-specific, and overall survival. Longer follow-up will help to determine whether these patients also have a higher risk of ipsilateral breast tumor relapse.
Wilder
Richard B
RB
Cancer Center of Irvine, Irvine, CA 92618, USA.
Curcio
Lisa D
LD
Khanijou
Rajesh K
RK
Eisner
Martin E
ME
Kakkis
Jane L
JL
Chittenden
Lucy
L
Agustin
Jeffrey
J
Lizarde
Jessica
J
Mesa
Albert V
AV
Macedo
Jorge C
JC
Ravera
John
J
Tokita
Kenneth M
KM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods; D001943:Breast Neoplasms / Q000737:chemistry* / Q000208:ethnology / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D016009:Chi-Square Distribution; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000517:prevention & control; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis*; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D015996:Survival Rate
D009363:Neoplasm Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone