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ESTRO 36 2017
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Conclusion
111
In-girentuximab-F(ab’)
2
has a high affinity to CAIX. For
optimal imaging of CAIX expression in human xenografts,
a tracer protein dose of 10 microgram should be
administrated 24 hours before scanning. These results
suggest that
111
In-girentuximab-F(ab’)
2
is a promising
tracer, in ongoing studies we will assess the tracer’s
applicability for treatment selection and monitoring.
PO-0966 Prognostic value of tissue necrosis,CD34 MVD
and CA-IX in head and neck cancer patients
D. Ou
1,2
, I. Garberis
3
, J. Adam
3
, P. Blanchard
1
, F.
Nguyen
1
, A. Levy
1
, O. Casiraghi
3
, P. Gorphe
4
, I. Breuskin
4
,
F. Janot
4
, S. Temam
4
, J. Scoazec
3
, E. Deutsch
1
, Y. Tao
1
1
Institut Gustave Roussy, Department of Radiation
Oncology, Villejuif, France
2
Fudan University Shanghai Cancer Center, Department
of Radiation Oncology, Shanghai, China
3
Institut Gustave Roussy, Department of Pathology,
Villejuif, France
4
Institut Gustave Roussy, Department of Head and Neck
Oncology, Villejuif, France
Purpose or Objective
Tumor hypoxia is adversely correlated to patient
prognosis. The aim of the present study was to investigate
the role of three hypoxia-related biomarkers in patients
with locally advanced head and neck squamous cell
carcinoma
(HNSCC)
treated
with
concurrent
chemoradiotherapy or bioradiotherapy.
Material and Methods
In tumor tissue material from 100 patients with known HPV
status, we evaluated the extent of tumor necrosis, the
expression level of CA-IX and the microvascular density
(MVD) measured as the density of CD34+ vascular
structures. The Kaplan–Meier method, univariate and
multivariate analyses, were used to analyze the
correlations
between
biomarker
status
and
clinicopathological characteristics and treatment
outcomes.
Results
We found a significant correlation between MVD and
overall stage (p=0.02) and T classification (p = 0.05). CA-
IX was significantly correlated with overall stage (p=0.03)
and N classification (p=0.04). There was a significant
inverse correlation between MVD and CA-IX expression (r=-
0.22, p = 0.03). Multivariate analysis showed that low MVD
combined with high CA IX-expression was a significant
independent prognostic factor for worse loco-regional
control (HR=2.6, 95%CI 1.1-5.0, p = 0.02) in the whole
population. However, in the p16-positive subgroup, the
difference was not significant (85.7% vs. 89.7%, p=0.73).
Patients treated with CRT had a better LRC than those
with BRT independent of MVD or CA-IX expression.
Conclusion
The combination of MVD and CA-IX status might give
additional prognostic information in HNSCC patients with
known HPV status.
PO-0967 Analysis of tumour microenvironment using
multi-parametric PET/MR imaging in HNSCC xenograft
models
S. Boeke
1
, R. Winter
2
, A. Menegakis
1
, P. Mena-Romano
2,3
,
M. Krueger
4
, E.C. Sezgin
1
, G. Reischl
4
, B. Pichler
4
, D.
Zips
1
, D. Thorwarth
2
1
University Hospital Tübingen, University Department of
Radiation Oncology, Tübingen, Germany
2
University Hospital Tübingen, University Department of
Radiation Oncology - Section for Biomedical Physics,
Tübingen, Germany
3
Pontificia Universidad Católica de Chile, Institute of
Physics, Santiago, Chile
4
Werner Siemens Imaging Center, Department of
Preclinical Imaging and Radiopharmacy, Tübingen,
Germany
Purpose or Objective
Hypoxia is a major determinant of outcome in
radiotherapy (RT) especially in head and neck squamous
cell carcinoma (HNSCC). Non-invasive imaging of tumour
microenvironment with multi-parametric PET/MRI, using
e.g. hypoxia specific tracers, is a potentially powerful
technology for personalisation of RT. The aim of this study
is to investigate simultaneously fMRI and hypoxia PET in
HNSCC xenografts during the course of fractionated RT.
Material and Methods
FaDu tumours (n=7) were xenografted on the right hind leg
of immunodeficient nude mice. After a growth period of
4-6 weeks multi-parametric FMISO-PET/MRI (7T, Bruker)
was performed before and after RT (10 x 2 Gy in two
weeks, small animal image guided RT platform, SAIGRT,
Dresden, Germany). Following the second imaging,
tumours were excised after injection of Pimonidazole and
Hoechst for further histological analysis. The imaging
protocol included a 80-90 min dynamic FMISO-PET
acquisition, anatomical T2w and diffusion-weighted MRI
(DWI, 9 b-values from 0 to 800 s/mm²) as well as DCE MRI.
T2w anatomical MRI data was used for precise manual
segmentation of the actual tumour region of interest
(ROI). Within each tumour ROI, mean and maximum
tumour-to-muscle ratios (TMR, TMR
max
) as well as mean
ADC values were analysed prior and post fractionated RT
treatment.
Results
Two animals presented with very small tumor volume (<
10 mm³) which did not allow for ROI-based analysis before
(n=1) or after (n=1) RT, respectively. The mean (SD)
volume was 479.3 (651.7) and 808.0 mm³ (1146.3), mean
ADC was 760.0 (138.3) and 950.0 10-³mm²/sec (176.9),
mean TMR at 80 min post injection (pi) was 1.42 (0.27) and
0.98 (0.17) and mean TMR
max
at 80 min pi was 2.47 (0.18)
and 1.75 (0.75) before and after 2 weeks of RT
respectively (cf. figure 1). Mean changes (SD) during the
two weeks of irradiation were 25.0% (71.64%), 19.7%
(24.0%), -31.7% (10.5%), -21.5 % (86.9%) for tumour
volume, ADC, TMR and TMR
max
, respectively.