ESTRO 36 Abstract Book

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S977 ESTRO 36 2017
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acute tolerance and can predict the absence or minimal
risk of late toxicity to treatment. Conclusion
This clinical case and the previously reported studies of
LRAB revealing similar rates of tumor control and survival
to radical cystectomy constitute a hope in terms of quality
of life for the most minimally invasive conservative
treatment in a selected group of patients with localized
MIBC.
EP-1805 Interstitial and superficial brachytherapy for
skin cancer
S. Brovchuk1, S. Romanenko1, N. Ratushnia1, O.
Vaskevych 1
1 Kyiv Regional Oncology Dispensary, Radiotherapy
department, Kyiv, Ukraine
Purpose or Objective
The main purpose of this work was to demonstrate the
capabilities of brachytherapy in skin cancer treatment.
Malignant skin lesions are highly frequent type of cancer.
Between two main non-melanoma forms, basal cell
carcinoma (BCC) and squamous cell carcinoma (SCC), BCC
accounts for about 70%, and SCC of about 30%. And while,
in our practice, for treatment of SCC in some cases
external beam radiotherapy (EBRT) was required to
irradiate regional lymph nodes, BCC, which is almost
always local, is perfectly suitable for monobrachytherapy
treatment.
Material and Methods
In 70% of cases (in our practice more than that) skin
tumors are located on head and neck, where high
conformity is extremely important. If invasion of a tumor
was less than 5 mm deep, accommodated to the surface
mold applications were used, if invasion of a tumor 5 mm
or more, interstitial implants were used (the examples are
presented on Image 1).
Radiation dose was delivered using high dose rate (HDR)
afterloader with Ir192 radioactive source and was
prescribed in case of BCC at 0.5 cm from visible lesion
(growth tumor volume GTV), the enclosed volume
corresponds to clinical tumor volume (CTV), in case of SCC
at 1-1.5 cm from GTV the enclosed volume corresponds to
CTV (planning tumor volume PTV=CTV).
Dose fractionation (every day treatment, 5 days per
week):
for BCC cases - dose per fraction (fr) 4Gy in 2 cases and
the total dose (TD) of 48Gy (12fr), 5.2Gy per fraction in 39
cases and TD=41.6Gy (8fr), 6Gy per fraction in 5 cases and
TD=42Gy(7fr);
for SCC cases - dose per fraction 5.2Gy in 5 cases and
TD=46.8Gy (9fr), dose per fraction in 6.3Gy 2 cases and
TD=44.1Gy(7fr).
Equivalent dose to standard fractionation was about 58-
60 Gy (a/b ratio was taken 6-7Gy (BCC) and 10Gy
(SCC)). Treatment planning was performed on CT images,
the ratio of CTV that received 150% of the prescribed dose
(CTV150 ) to CTV100 was kept below 0.45 (CTV150/ CTV100-
<0.45), that constrain in interstitial technique, where
radiation source is inside the tissue, is achieved when
spacing between implants is about 1-1.2 cm.
Results
Totally 53 patients (46 – BCC cases, 7 – CSS cases) were
treated acording to the described method during clinical
work in 2013 (clinical example is presented on Image 2);
median follow-up 2.5 years (range from 2 to 3 years); 4
patients had local recurance and one lymph node failure
(3-BCC cases and 2 (1 local+1 lymph node) – CSS cases).
Conclusion
Brachytherapy method of delivering radiation dose is
naturally the most conformal, which also is challenging,
but using interstitial implants or, accommodated to the
skin surface, mold applications, gives good results. Dose
per fraction of 6Gy and more lead to higher late
complications (fibrosis in our experience).
EP-1806 HDR brachytherapy for superficial non-
melanoma skin cancers.
C. De la Pinta1, T. Muñoz1, J. Dominguez 1, A. Montero2
1Hospital Ramon y Cajal, Radiation Oncology, Madrid,
Spain
2Radiation Oncology, Madrid, Spain
Purpose or Objective
The aim of this study was to evaluate the clinical and
cosmetic outcomes in patients treated with high-dose-rate
brachytherapy for non-melanoma skin cancer and disease-
specific and overall survival.
Material and Methods
All patients referred for interstitial brachytherapy in our
centre from 2007 to 2016 with non-melanoma skin cancer
without distant metastases were retrospectively analysed
(n=13). Median age was 7 years (range 54-88). Treatment
consisted of brachytherapy alone (10p) or after surgery
(3p). Patients with histologically confirmed squamous
carcinoma (4p), and basal cell carcinoma (9p). All lesions
were macroscopic. Lesions were located on the head and
neck: nasal skin (5p), periocular skin (4p) and ear skin
(4p). All patients were treated with interstitial
brachytherapy median implant dose 53 Gy (range 45-
66Gy).
Inclusion criteria were as follows: head and neck location
and malignant tumors.
Results
From January 2007, 13 patients were treated. Median
follow-up was 36 months (range 6-68 months), local
control was achieved on clinical examination.
Acute toxicities (8/13p) consisted of ephitelitis grade 1
(2p) and grade 2 (6p). Cosmesis was good or excellent in
12p. Late skin hypopigmentation were observed in 7
patients. Not acute toxicities grades 3 or 4 were reported.
Grade 4 complication rate for all patients was 7,6% (one
patient presented skin necrosis)
Among 13 patients studied, 4 lost follow-up and they were
excluded from the survival analysis.
Preservation of organ functions were in all patients.
Using Kaplan-Meier analysis overall survival after minimum
follow-up of 36 months was 93% and disease-free survival
was 75%. One patient had a locoregional recurrence.
Conclusion
Interstitial brachytherapy is a good choice to deliver high-
dose radiation in tumor after surgery or as an exclusive
treatment in non-melanoma skin cancers. This treatment
offers adequate locoregional control with acceptable
range of complications.
EP-1765 Volume delineation based on 18FDG-PET and
MRI in head and neck cancer treated with IG-VMAT
L. Méndez Blanco1, C. Herrero2, M. Fueyo1, A. Martos1, D.
Abad 2, P. Santin1, S. Palizas1, D. Alonso1, A. Rios1, M.
Vilches2, R. Cabanillas1
1Institute of Molecular and Oncological Medicine of
Asturias, Radiation Oncology, Oviedo, Spain
2Institute of Molecular and Oncological Medicine of
Asturias, Medical Physics, Oviedo, Spain
Purpose or Objective
Image Guided-Volumetric Modulated Arc Therapy (IG-
VMAT) is being increasingly used to treat locally advanced
head and neck cancers. In this context 18-FDG-PET and
MRI are becoming especially useful for accurate target
volume delineation.
Material and Methods
Between November 2012 and October 2015, 38 patients
with head and neck carcinomas were treated at our
institution with IG-VMAT. Sites included were the
nasopharynx (14), oropharynx (5), hypopharynx (4), larynx
(6), paranasal sinuses and nasal cavity (3), thyroid (1),
parotid (1) and metastatic neck nodes from an unknown
primary (4). Each patient underwent endoscopy, contrast
enhanced CT, MRI and 18-FDG PET scans. Plans were