by Norbert Mészáros, Tibor Major, Gábor Stelczer, Levente
Jánváry, Zoltán Zaka, Dávid Pukancsik, Zoltán Takácsi-Nagy, János Fodor Md,
Csaba Polgár
The Breast: October
29, 2020
Purpose
To present the 7-year results of accelerated partial breast
irradiation (APBI) using three-dimensional conformal (3D-CRT) and image-guided
intensity-modulated radiotherapy (IG-IMRT) following breast-conserving surgery
(BCS).
Patients and methods
Between 2006 and 2014, 104 patients were treated with APBI
given by means of 3D-CRT using 3–5 non-coplanar, isocentric wedged fields, or
IG-IMRT using kV-CBCT. The total dose of APBI was 36.9 Gy
(9 × 4.1 Gy) using twice-a-day fractionation. Survival results,
side effects and cosmetic results were assessed.
Results
At a median follow-up of 90 months three (2.9%) local
recurrences, one (0.9%) regional recurrence and two (1.9%) distant metastases
were observed. The 7-year local (LRFS), recurrence free survival was 98.9%. The
7-year disease-free (DFS), metastases free (MFS) and overall survival (OS) was
94.8%, 97.9% and 94.8%, respectively. Late side effects included G1 skin
toxicity in 15 (14.4%), G1, G2, and G3 fibrosis in 26 (25%), 3 (2.9%) and 1
(0.9%) patients respectively. Asymptomatic (G1) fat necrosis occurred in 10
(9.6%) patients. No ≥ G2 or higher late side effects occurred with
IMRT. The rate of excellent/good and fair/poor cosmetic results was 93.2% and
6.8%, respectively.
Conclusion
7-year results of APBI with 3D-CRT and IG-IMRT are
encouraging. Toxicity profile and local tumor control are comparable to other
series using multicatheter interstitial brachytherapy. Therefore, these
external beam APBI techniques are valid alternatives to whole breast irradiation
and brachytherapy based APBI.
