ESTRO 36 Abstract Book

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S299 ESTRO 36 2017
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recently published subgroup analysis of the Florence trial
concerning patients aged 70 years or older, showed an
IBTR rate at 5 years of 1.9%, and significantly better
results in terms of acute skin toxicity, in favor of APBI arm.
Therefore, tumor biology seems to play a crucial role on
patient’s selection; treatment decisions should always
consider disease stage, comorbidities, and tumor
biomarkers. Longer follow-up of recently presented
studies with appropriately selected patients will be
critical to define the rates of local control, survival, and
long-term toxicity before APBI could be accepted as a
standard alternative to conventional WBI. Outcome results
from ongoing unpublished prospective trials (e. g. RAPID,
IRMA, SHARE, NSABP B-39/RTOG 0413 trials) are awaited.
SP-0567 Partial breast irradiation with brachytherapy:
changing patient selection based on current evidence
C. Polgár 1
1 National Institute of Oncology, Center of Radiotherapy,
Budapest, Hungary
In the last decades accelerated partial breast irradiation
(APBI) has been intensively evaluated in prospective phase
II and III clinical trials as a possible alternative to whole
breast irradiation (WBI). Majority of these trials – using
conservative patient selection criteria and proper
treatment technique – were successful in yielding an
annual local recurrence rate in the range of 0 to 1%. The
10-year results of the Hungarian phase III trial and more
recently the 5-year results of the GEC-ESTRO phase III trial
also demonstrated non-inferiority of APBI with intertitial
brachytherapy compared to WBI. Despite variability in
selection criteria, the majority of women treated within
these trials were >40 years old, presented with node
negative invasive ductal carcinomas up to 3 cm, without
extensive intraductal component (EIC), and resected with
clear margins. Based on available experience international
guidelines have been published by the American
Brachytherapy Society (ABS), the American Society for
Therapeutic Radiology and Oncology (ASTRO), and the
GEC-ESTRO (Table 1.)
Table 1. International guidelines for APBI patient selection
Criterion ABS ASTRO ESTRO
Age (years) ≥ 50 > 50 > 50
Tumor size
(cm)
≤ 3 ≤ 2 (DCIS ≤ 3) ≤ 3
Histology All ivasive subtypes
and DCIS
Invasive ca. (excl. ILC)
or low-risk DCIS
Invasive ca.
(excl. ILC)
Margin
status
Negative Clear margin ≥ 2 mm Clear margin ≥
2 mm
ER status Any Positive Any
LVI Not allowed Not allowed Not allowed
Nodal status pN0 pN0 pN0
DCIS: ductal carcinoma in situ; IDC: invasive ductal
carcinoma; ILC: invasive lobular carcinoma; ER: estrogen
receptor; LVI: lymphovascular invasion.
However controversy exists regarding the possible
extension of selection criteria including patients younger
than 50 years, women with invasive lobular carcinomas or
DCIS, or patients with clear but close (< 2 mm) surgical
margins. Ongoing clinical research actually focuses on
better definition of candidates for APBI. As data from
ongoing phase III trials mature, guidelines for patient
selection should be revised and might be extended.
However until additional long-term outcome reports of
phase III trials are available, conservative patient
selection criteria (as defined by the GEC-ESTRO and
ASTRO) should be considered for selecting candidates for
APBI.
OC-0568 Accelerated PBI VS standard radiotherapy
(IRMA trial): interim cosmetic and toxicity results
B. Meduri1, A. Baldissera2, M. Galeandro3, E. Donini2, G.
Tolento4, P. Giacobazzi 1, T. Calmieri3, P. Vasilyeva1, A.G.
Morganti4, S. Parisi5, S. Kaleci 6, F. Lohr 1, R. D'amico6,
P.M. Poortmans7, F. Bertoni1, G.P. Frezza2
1Azienda Ospedaliero-Universitaria Policlinico di
Modena, Radiotherapy Unit, Modena, Italy
2Ospedale Bellaria – AUSL di Bologna, Radiotherapy Unit,
Bologna, Italy
3Arcispedale S..Maria Nuova – Azienda Ospedaliera di
Reggio Emilia, Radiotherapy Unit, Reggio Emilia, Italy
4University of Bologna, Radiation Oncology Center-
Department of Experimental- Diagnostic and Specialty
Medicine - DIMES, Bologna, Italy
5Casa del sollievo della sofferenza – S. Giovanni Rotondo,
Radiotherapy Unit, Foggia, Italy
6Università di Modena e Reggio Emilia, Department of
Medical Statistic, Modena, Italy
7Radboud University Medical Center, Department of
Radiation Oncology, The Netherlands, The Netherlands
Purpose or Objective
To report interim cosmetic and toxicity results in patients
(pts) enrolled from 5 italian centers in the randomized
IRMA trial.
Material and Methods
Women age ≥ 49 years with invasive breast cancer < 3 cm,
pN0-1, were randomly assigned after breast-conserving
surgery to 3D-CRT APBI (38.5 Gy in 10 fractions twice
daily) or WBI (50 Gy in 25 daily fractions ± boost). Pts
received adjuvant systemic therapy according to
institutional guidelines. Cosmesis was assessed according
to IRMA protocol parameters. Toxicity was scored
according to RTOG tables.
Results
From March 2007 to December 2013, 983 pts were enrolled
in IRMA from 5 italian centers (425 Bologna Bellaria, 240
Modena, 163 Reggio Emilia, 101 Bologna S.Orsola, 54
S.Giovanni Rotondo). Median follow-up was 5 years. No
difference was observed in adverse cosmesis (fair and
poor) among pts treated with APBI compared with WBI as
assessed by physicians (20% vs 21.8% 1 year, 20% vs 19% 3
years) and by patients (14% vs 16% 1 years, 14% vs 14% 3
years). G3 acute skin toxicity was rare in both treatment
arms (0% PBI vs 1.4% WBI), no further G3-4 acute toxicities
were observed. G3-4 late skin toxicity was 0.42% (APBI) vs
0.79% (WBI) (p=0.4); G3-4 late subcutaneous tissue
toxicity was 1.5% (APBI) vs 1.2% (WBI) (p=0.7); 2 rib
fractures were observed in PBI patients; no further G3-4
late toxicities were observed. Axillary dissection (vs
sentinel node) correlated with G3-4 late subcutaneous
tissue toxicity (3.7% vs 0.9%, p<0.01); no correlation of
toxicity with adjuvant chemotherapy was observed.
Conclusion
APBI with 3D-CRT resulted in similar acute and late
toxicity and good/excellent cosmetic results compared
with standard WBI. Additional follow-up is needed to
confirm these results.
OC-0569 Comparison of clinical outcome of APBI by
interstitial brachytherapy as per ESTRO &ASTRO
guidelines
T. Telkhade1, T. Wadasadawala1, R. Upereti2, R. Sarin1, R.
Jalali1, R. Badwe3, V. Parmar3, S. Gupta4, A. Budrukkar1
1Tata Memorial Hospital, Radiation oncology, Mumbai,
India
2Tata Memorial Hospital, Medical Physics, Mumbai, India
3Tata Memorial Hospital, Surgical oncology, Mumbai,
India
4Tata Memorial Hospital, Medical oncology, Mumbai, India
Purpose or Objective
Lack of consistency in recommendations given by ASTRO
and ESTRO for accelerated partial breast irradiation (APBI)
with respect to clinicopathological criteria poses a
dilemma for patient selection.The purpose of this study is