Long-term outcome with interstitial brachytherapy in the management of patients with early-stage breast cancer treated with breast-conserving therapy.
OBJECTIVE
We reviewed our institution's experience with interstitial implant boosts to determine their long-term impact on local control and cosmetic results.


METHODS
Between January 1, 1980 and December 31, 1987, 390 women with 400 cases of Stage I and II breast cancer were managed with breast-conserving therapy (BCT) at William Beaumont Hospital. All patients were treated with an excisional biopsy and 253 (63%) underwent reexcision. Radiation consisted of 45-50 Gy external beam irradiation to the whole breast followed by a boost to the tumor bed to at least 60 Gy using either electrons [108], photons [15], or an interstitial implant [277] with either 192Ir [190] or 125I [87]. Long-term local control and cosmetic outcome were assessed and contrasted between patients boosted with either interstitial implants, electrons, or photons.


RESULTS
With a median follow-up of 81 months, 25 patients have recurred in the treated breast for a 5- and 8-year actuarial rate of local recurrence of 4 and 8%, respectively. There were no statistically significant differences in the 5- or 8-year actuarial rates of local recurrence using either electrons, photons, or an interstitial implant. Greater than 90% of patients obtained a good or excellent cosmetic result, and no statistically significant differences in cosmetic outcome were seen whether electrons, photons, or implants were used.


CONCLUSIONS
We conclude that patients with Stage I and II breast cancer undergoing BCT and judged to be candidates for boosts can be effectively managed with LDR interstitial brachytherapy. Long-term local control and cosmetic outcome are excellent and similar to patients boosted with either electrons or photons.
Vicini
F A
FA
Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48073, USA.
Horwitz
E M
EM
Lacerna
M D
MD
Dmuchowski
C F
CF
Brown
D M
DM
White
J
J
Chen
P Y
PY
Edmundson
G K
GK
Gustafson
G S
GS
Clarke
D H
DH
Gustafson
G S
GS
Matter
R C
RC
Martinez
A A
AA
D000328:Adult; D001706:Biopsy; D001918:Brachytherapy; D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D007496:Iridium Radioisotopes / Q000627:therapeutic use; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000601:surgery; D016879:Salvage Therapy; D016896:Treatment Outcome
D007457:Iodine Radioisotopes; D007496:Iridium Radioisotopes