Biopsy findings after breast conservation therapy for early-stage invasive breast cancer.
OBJECTIVE
To determine the patterns and factors predictive of positive ipsilateral breast biopsy after conservation therapy for early-stage breast cancer.


METHODS
We performed a retrospective review of Stage I-II breast cancer patients initially treated with lumpectomy and radiotherapy between 1977 and 1996, who later underwent post-treatment ipsilateral breast biopsies.


RESULTS
A total of 223 biopsies were performed in 193 treated breasts: 171 single and 22 multiple biopsies. Of the 223 biopsies, 56% were positive and 44% were negative for recurrence. The positive biopsy rate (PBR) was 59% for the first and 32% for subsequent biopsies. The median time to the first post-treatment biopsy was 49 months. Of the patients with negative initial biopsy findings, 11% later developed local recurrence. The PBR was 40% among patients with physical examination findings only, 65% with mammographic abnormalities only, and 79% with both findings (p = 0.001). Analysis of the procedure type revealed a PBR of 86% for core and 58% for excisional biopsies compared with 28% for aspiration cytology alone (p = 0.025). The PBR varied inversely with age at the original diagnosis: 49% if >or=51 years, 57% if 36-50 years, and 83% if <or=35 years (p = 0.05). The PBR correlated directly with the interval after radiotherapy: 49% if <or=60 months, 59% if 60.1-120 months, 77% if 120.1-180 months, and 100% if >180 months after completing postlumpectomy radiotherapy (p = 0.01). The PBR was not linked with recurrence location, initial pathologic T or N stage, estrogen receptor/progesterone receptor status, or final pathologic margins (all p >or= 0.15).


CONCLUSIONS
After definitive radiotherapy for early-stage breast cancer, a greater PBR was associated with the presence of both mammographic and clinical abnormalities, excisional or core biopsies, younger age at the initial diagnosis, and longer intervals after radiotherapy completion.
Vapiwala
Neha
N
Department of Radiation Oncology, Hospital of University of Pennsylvania, Philadelphia, PA 19104, USA. vapiwala@xrt.upenn.edu
Starzyk
Jill
J
Harris
Eleanor E
EE
Tchou
Julia C
JC
Boraas
Marcia C
MC
Czerniecki
Brian J
BJ
Rosato
Ernest F
EF
Orel
Susan G
SG
Solin
Lawrence J
LJ
D000328:Adult; D000367:Age Factors; D000368:Aged; D001706:Biopsy / Q000706:statistics & numerical data; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy / Q000601:surgery; D005260:Female; D006801:Humans; D008327:Mammography; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009367:Neoplasm Staging; D012189:Retrospective Studies