ESTRO 36 Abstract Book

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S118 ESTRO 36 2017
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Purpose or Objective
Post-operative radiation therapy (PORT) is often used for
breast cancer patients who received neoadjuvant
chemotherapy (CT) followed by surgery. Nevertheless, the
optimal time to initiation of PORT is unclear.
Material and Methods
Between 2008 to 2014, data from non metastatic breast
cancer patients who underwent PORT after neoadjuvant
CT and surgery were assessed retrospectively. Patients
were categorized into three groups according to the time
between surgery and PORT: <8 weeks, 8-16 weeks and >16
weeks. The primary endpoint was disease free survival
(DFS). Multivariate Cox regression adjusted for molecular
profile, histological grade (HG), age, clinical stage and
complete pathologic response (pCR) was used to estimate
survivals outcomes. Binary logistic regression model was
used to calculate the adjusted odds ratios for recurrence.
Results
Among the 581 patients included, the vast majority had
clinical stage III (75%) and received antracycline-taxane
based neoadjuvant CT (95%). Forty-three patients
received PORT within 8 weeks, 354 in 8-16 weeks and 184
after 16 weeks from surgery. With a median follow-up of
32 months, beginning radiation therapy up to 8 weeks
after surgery was associated with better DFS (HR 0.36;
95%CI 0.146-0.914; p=0.03) and a trend in better OS (HR
0.223; 95%CI 0.07-1.14; p=0.08). The factors associated
with less recurrence rate were: PORT at 8 weeks
(OR=0.33; 95% CI 0.12-0.90; p=0.03), stage I-II (OR=0.41;
95%CI 0.25-0.69; p=0.001) and pCR (OR=0.15; 95%CI 0.07-
0.32; p<0.001).
Conclusion
PORT started up to 8 weeks after surgery was associated
with better DFS and a trend in better OS in a
predominantly stage III population of breast cancer
patients submitted to neoadjuvant CT. Our findings
suggest that early initiation of radiation therapy should be
granted for these patients.
PV-0237 Management and outcome of local failure after
intraoperative partial breast irradiation
M.C. Leonardi1, L. Tomio 2, G.B. Ivaldi3, G. Catalano4, M.
Alessandro5, C. Fillini 6, A. Ciabattoni7, M. Guenzi 8, C.M.
Francia9, C. Fodor10, F. Rossetto10, B.A. Jereczek –Fossa9,
R. Orecchia11, AIRO IORT Working Group12
1 Istituto Europeo di Oncologia - IEO, Division of
Radiotherapy, MIlan, Italy
2 Santa Chiara Hospital, Radiotherapy Unit, Trento, Italy
3 Fondazione Salvatore Maugeri, Oncology unit, Pavia,
Italy
4 Multimedica Holding Clinical Institute, Unit of
Radiotherapy, Castellanza, Italy
5 Ospedale di Città di Castello, Radioterapia Oncologica,
Città di Castello, Italy
6 Azienda Ospedaliera Santa Croce e Carle, Department
of Radiation Oncology, Cuneo, Italy
7 San Filippo Neri Hospital, Department of Radiotherapy,
Rome, Italy
8 IRCC Azienda Ospedaliero-Universitaria San Martino IST,
UOC Oncologia Radioterapica, Genoa, Italy
9 European Institute of Oncology - University of Milan,
Department of Radiation Oncology - Department of
Oncology and Hemato-oncology, Milan, Italy
10 European Institute of Oncology, Department of
Radiation Oncology, Milan, Italy
11 European Institute of Oncology - University of Milan,
Department of Medical Imaging and Radiation Sciences -
Department of Oncology and Hemato-oncology, Milan,
Italy
12 Associazione Italiana Radioterapia Oncologica,
intraoperative radiotherapy working group, -, Italy’
Purpose or Objective
To assess the outcome and the patterns of failure in
patients (pts) who develop an ipsilateral in breast
recurrence (IBTR) after breast conservative surgery (BCS)
partial breast irradiation (PBI) with intraoperative
radiotherapy with electrons (IORT).
Material and Methods
The Italian IORT Working Group promoted collection of
information regarding clinical management and outcome
of pts who experienced a failure of breast conservative
treatment after being given IORT as sole radiotherapy (full
dose at 21 Gy). Data from 8 Italian radiation centers were
recorded in a central dedicated database for a total of 228
pts. Pts gave informed consent for the use of anonymized
data for research and training purposes. Clinical outcomes
included IBTR, nodal failure, distant metastases, disease-
free survival and overall survival. Treatment options were
recorded.
Results
Median time from BCS with IORT full dose (21 Gy) to IBTR
was of 3.9 years (range 0.4-15 years). 128/228 pts (56.1%)
experienced a true/marginal miss IBTR, 51/228 (22.3%)
presented local relapse in a breast site far from the index
quadrant, 8/228 (3.5%) relapsed with lymphangitis
features. In about 15% of cases, local relapse was
combined with nodal regional or distant metastases.
Axillary failure alone was observed in 4 pts (1.7%), while
bone metastases without locoregional recurrence in only
1 case (0.4%). Surgical salvage therapy was carried out
with different modalities. Mastectomy was performed in
129/228 patients (56.5%), 7.4% of them received also
postmastectomy radiotherapy. Second conservative
surgery with or without axillary investigation was given to
88 patients (38.5%). Interestingly, patients re-operated on
conservatively received additional radiotherapy: 44
(19.2%) were treated with whole breast irradiation
(WBRT), using conventional or hypofractionated schemes,
while 22 (9.5%) were treated with PBI, using either
intraoperative radiotherapy with electrons or conformal
external beam radiotherapy. Only 8 pts didn’t undergo
reoperation due to disease progression. Median follow-up
after salvage surgery was 3.5 years (0-12 years). In this
time frame, 3.3% of pts developed a second isolated local
relapse, while in other 3.3% of cases the second local
relapsed combined with another event (nodal, distant,
contralateral tumor reappearance). Distant metastases as
first site of failure after salvage treatment occurred in
12.2% of pts. Status at last follow-up was: 70% alive
without disease, 16% alive with disease, 12% died of
disease.
Conclusion
Treatment failure mostly consisted of local I n breast
reappearance at or near the irradiated site. While most of
pts received salvage mastectomy, second BCS with
additional radiotherapy, either WBRT or PBI, is feasible.
Overall survival was lower than that reported by the
randomized ELIOT trial and therefore a multivariate
analysis is being performed to identify predictor and
prognostic factors.
PV-0238 Use of Stereotactic Ablative Radiotherapy in
Non-Small Cell Lung Cancer Measuring 5 cm or More
H. Tekatli1, S. Van 't Hof1, E.J. Nossent2, M. Dahele1,
W.F.A.R. Verbakel1, B.J. Slotman1, S. Senan1
1VU University Medical Center, Radiation Oncology,
Amsterdam, The Netherlands
2VU University Medical Center, Pulmonology,
Amsterdam, The Netherlands
Purpose or Objective
Stereotactic ablative radiotherapy (SABR) is currently not
the guideline recommended treatment for lung tumors
measuring 5 cm or more. However, improvements in
treatment planning and delivery have enabled better
sparing of normal organs, leading to an increased use of
SABR for these tumors.
Material and Methods