Intraoperative radiotherapy given as a boost after breast-conserving surgery in breast cancer patients.
Conventional radiotherapy after breast-conserving therapy is confined to 50-55 Gy external beam radiation therapy (EBRT) to the whole breast and 10-16 Gy external boost radiation to the tumour bed or brachytherapy to the tumour bed. Local recurrence rate after breast-conserving surgery varies between 5 and 18%. External boost radiation can partially miss the tumour bed and therefore can result in local failure. Intra-operative radiotherapy (IORT) as a high precision boost can prevent a 'geographical miss'. From October 1998 to December 2000, 156 patients with stage I and stage II breast cancer were operated upon in a dedicated IORT facility. After local excision of the tumour, the tumour bed was temporarily approximated by sutures to bring the tissue in the radiation planning target volume. A single dose of 9 Gy was applied to the 90% reference isodose with energies ranging from 4 to 15 MeV, using round applicator tubes 4-8 cm in diameter. After wound healing, the patients received additional 51-56 Gy EBRT to the whole breast. No acute complications associated with IORT were observed. In 5 patients, a secondary mastectomy had to be performed because of tumour multicentricity in the final pathological report or excessive intraductal component. 2 patients developed rib necroses. In 7 patients, wound healing problems occurred. After a mean follow-up of 18 months, no local recurrences were observed. Cosmesis of the breast was very good and comparable to patients without IORT. Preliminary data suggest that IORT given as a boost after breast-conserving surgery could be a reliable alternative to conventional postoperative fractionated boost radiation by accurate dose delivery and avoiding geographical misses, by enabling smaller treatment volumes and complete skin-sparing and by reducing postoperative radiation time by 7-14 days.
Landesklinik für Spezielle Gynäkologie, Landeskliniken Salzburg, Müllner Hauptstrasse 48, 5020, Salzburg, Austria. r.reitsamer@lks.at
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R
Reitsamer
F
F
Peintinger
F
F
Sedlmayer
M
M
Kopp
C
C
Menzel
W
W
Cimpoca
S
S
Glueck
H
H
Rahim
P
P
Kopp
H
H
Deutschmann
F
F
Merz
M
M
Brandis
H
H
Kogelnik
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D015412:Mastectomy, Segmental / Q000379:methods; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D011446:Prospective Studies; D016896:Treatment Outcome