Preliminary results with accelerated partial breast irradiation in high-risk breast cancer patients.
OBJECTIVE
To analyze prognostic factors in adequately staged breast cancer patients who were treated with accelerated partial breast irradiation (APBI).


METHODS
Axillary staging was required for invasive carcinomas. Between February 2003 and June 2009, 204 women with early stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions 2 times per day. Six patient characteristics were examined for prognostic significance: (1) N stage, (2) estrogen receptor (ER) status, (3) histologic subtype, (4) margin status, (5) age, and (6) tumor size. The median followup was 22 months.


RESULTS
There were three failures in the ipsilateral breast (all were elsewhere failures), one relapse in the axilla, and seven relapses at any site. The presence of positive axillary node(s) had a significant adverse effect on ipsilateral breast tumor control (p=0.045) and locoregional control (p=0.001). The presence of an ER (-) tumor had a significant adverse effect on relapse-free survival (p=0.04).


CONCLUSIONS
The patients with positive axillary node(s) were at increased risk for failure elsewhere in the ipsilateral breast or axilla, and the patients with ER (-) tumors were at increased risk for relapse at any site. However, it is unclear whether the pN1 and ER (-) patients would have faired any better if they had received whole breast irradiation rather than APBI. We believe that the patients with positive axillary node(s) or ER (-) tumors should be treated on clinical trials to better define the role of APBI.
Wilder
Richard B
RB
Department of Radiation Oncology, Cancer Center of Irvine, Irvine, CA 92618, USA. richardbwilder@yahoo.com
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
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012307:Risk Factors; D016896:Treatment Outcome; D055815:Young Adult