ESTRO 36 Abstract Book

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S626 ESTRO 36 2017
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Fig 2: Disease free survival according to TNM staging
system
Conclusion
Many authors are pointing the lack of uniformity and
discriminating power of the T4 subcategory of TNM
classification. The subgroup of T4 small tumors have a
better OS and DFS in our retrospective study.
We hope that adding the T4s subcategory to the TNM
classification, will encourage providing more data about
its prognosis.
EP-1161 Hypofracionated Radiation Therapy in Breast
Cancer: retrospective analysis of late toxicity
P. Ferrazza1, F. De Renzi 1, T. Iannone1
1 Ospedale Civile San Martino, Radioterapia, Belluno,
Italy
Purpose or Objective
Various randomised trials have established the role of
hypofracionated radiotherapy (HRT) in breast cancer. The
aim of our retrospective analysis is to evaluate late toxicy
and cosmetic results in patients treated with
hypofracionated radiotherapy after breast conserving
surgery followed or not by chemoterapy.
Material and Methods
We included in this analysis patients (pts) treated with
breast conserving surgery and HRT with a follow-up of at
least 4 years. From january 2007 to september 2012, 239
pts with early breast cancer (TNM stage pTis pT1-2 and N0-
N1mic) were treated with adjuvant hypofractionated
radiation therapy. 40 pts underwent anthracycline-taxane
based chemotherapy befor HRT, 161 pts received only
hormone therapy and 38 pts received no other therapies.
Total dose delivered to whole breast was 45.66 Gy/16 fx
in 233 pts and 42.4 Gy/16 fx in only 6 pts. 36 pts received
a sequential boost on tumor bed (10 Gy/5 fx).
Late toxicity was recorded according RTOG/EORTC Late
Radiation Morbidity Scoring Schema.
Results
Median age was 61 years (range 36-86 years). 38/239 had
DCIS, 158/239 pts had stage I disease and 43/239 had stage
II disease. Median follow-up was 61 months. Most common
acute toxicity was skin grade 1 (56%) and grade 2 (36.8%).
Only 1 pts presented grade 3 skin toxicity.
112 pts present grade 1 skin late toxicity (58 pts grade 1
edema, 38 pts grade 1 pigmentation changes , 7 pts
telangiectasia , 9 pts grade 1 atrophy and 6 pts both
edema and pigmentation change ). No >grade 3 events
were reported. Only 3 grade 3 fibrosis occurred.
The cosmetic results were excellent in 76% pts, good in
19% pts and fair in 5% pts.
No pulmonary or cardiac toxicity was observed.
Although the series is not homogeneus, there was no
significant difference in the incidence of acute or late
toxicity in pts that underwent or not to chemotherapy.
Conclusion
In our seriesHRT is well tollerated with a good toxicity
profile and a good cosmetic result. There is no clear
evidence that chemotherapy has an impact to acute or
late skin toxicity after HRT.
In our analysis we can not evaluate the role that have
sequential boost in causing late toxicity.
EP-1162 Non surgical breast conserving treatment
using a new radiosensitizer
T. Shimbo 1, K. Yoshida1, N. Yoshikawa1, H. Yoshioka1, M.
Nakata1, Y. Narumi1, T. Komori1, H. Matsutani1, T.
Hamada1, Y. Uesugi2
1Osaka Medical College, Radiation Oncology, Osaka,
Japan
2Kansai University of Welfare Sciences, Medical
treatment for health, Kashihara, Japan
Purpose or Objective
The purpose of this clinical study was to clarify a non-
surgical breast-conserving therapy (BCT) using a new
radiosensitizing agent for the early stage breast cancer
patients who rejected surgery. This new radiosensitizer,
named KORTUC (Kochi Oxydol-Radiation Therapy for
Unresectabe Carcinomas) containing 0.5% hydrogen
peroxide and 0.83% sodium hyaluronate has been
developed for intra-tumoral injection in various tumors.
Hydrogen peroxide is the only agent known to be capable
of inactivating antioxidative enzymes and producing
oxygen when applied topically to tumor tissues. By the
addition of sodium hyaluronate, which makes the solution
more viscous and slows the degradation of hydrogen
peroxide, allowing long-acting radiosensitization of the
local tumor tissue.
Material and Methods
A total of five early stage breast cancer patients (stage I,
2; stage II, 3) who rejected surgery were enrolled in the
KORTUC trial after providing a fully informed consent. The
mean age of the patients was 67.5 years (range; 38-
80). The tumor size was 24.6mm (range; 14-47). A
maximum of 6 mL of the radiosensitizar agent was
injected into breast tumor tissue twice a week under
ultrasonographic guidance. We used hypo-fractionated
radiotherapy with conventional linear accelerator. Forty-
four Gy in 16 fractions were irradiated for whole breast
and ipsilateral axillary region with tangential field, and an
additional electron boost of 9Gy in 3fractions were
delivered for primary tumor site.
Results
Treatment was well tolerated with minimal adverse
effects in all patients. No patients showed any significant
complications other than mild dermatitis. Three patients
with estrogen receptor-positive tumors were also started
on hormone therapy following KORTUC treatment. All
patients showed clinically complete response (cCR). The
mean duration of a follow-up was 15.6 months
(5/23/26/27/44 months), respectively. All patients were
alive with no evidence of disease at present. The mean
period taken to confirm cCR on the breast contrast-
enhanced CT, MRI or PET-CT was approximately 8.2
months. Cosmetically, all patients evaluated as having an
excellent appearance in their ipsilateral breast.
Conclusion
Non-surgical BCT (KORTUC-BCT) can be performed safely
and effectively for patients with early stage breast cancer.
KORTUC-BCT can be one of the treatment options to
breast cancer patients who rejected surgery.
EP-1163 A Prospective Evaluation of Lumpectomy
Cavity Volume Changes During Whole Breast
Radiotherapy