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S17
ESTRO 36 2017
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testicular classic seminoma (CS) treated with RT and
prospectivelly evaluated by abdominal vascular
ultrasonography.
Material and Methods
Forty-two CS patients (median age 34 years, range 16-56)
who had undergone radical inguinal orchiectomy were
enrolled in this study. Twenty-six patients underwent
post-surgery RT (median total dose 25.2 Gy, range 25.05–
43.2), 2 of them also received chemotherapy (CHT), and
16 patients were treated with surgery alone or by surgery
followed by CHT (control group).For RT group, dose
volume histograms (DVHs) for contoured structures
(abdominal arteries and kidneys) were extracted and near
maximum dose (D
2%
) and mean dose (D
mean
) metrics
analyzed. The presence of stenosis in an abdominal vessel
and renal resistive index (RRI) were evaluated by
abdominal echo-color Doppler and considered as
indicators of vascular damage. The presence and severity
of stenosis was classified according to validated criteria
reported in table 1.
The average RRI (aRRI) over the left and right kidneys was
also computed. Statistical analysis was performed first
comparing RT group and control-group by Chi-square and
Mann-Whitney tests. For RT group, univariate logistic
regression analysis was performed by Spearman’s rank
correlation coefficient (Rs) to evaluate correlations
between different factors with the incidence of stenosis
and with RRI. The impact of artery dosimetric factors was
analyzed comparing the stenotic arteries versus normal
ones. Similarly, the kidney dosimetric analysis was
performed on each kidney separately. The area under the
Receiver Operator Characteristic (ROC) curve (AUC) was
used to evaluate the test accuracy.
Results
After a median follow-up of 77.4 months (range 48-120
months), stenosis was observed in 8 patients (31%) in the
RT group but none in the control group (p=0.016). A
significantly higher median aRRI was also observed in the
RT group compared with control group (0.63 vs 0.60,
p=0.032). Age at RT was the only clinical risk factor for
stenosis (Rs=-0.529, p=0.005). Artery mean dose was
correlated with stenosis [Rs=0.238, p=0.008, AUC=0.85,
95%CI 0.77-0.91] and kidney mean dose with dichotomized
RRI variable using its mean value (0.62) [Rs=0.417,
p=0.013, AUC=0.76, 95%CI 0.58-0.89], respectively. ROC
curves are displayed in figure 1.a and 1.b.
Conclusion
Late vascular damage represents a potential effect of
abdominal RT even at moderate-low radiation dose.
Younger age at irradiation as well as artery and kidney
mean doses are associated with increased risk.
Ultrasound-based follow-up may allow for early detection
of asymptomatic vascular radiation-induced damage,
helping to prevent severe vascular events.
Poster Viewing : Session 1: Haematology / Paediatrics /
Sarcoma
PV-0042 Fractionated-TBI schedules prior to allograft:
Study from the Acute Leukemia Working Party (EBMT)
Y. Belkacemi
1
, M. Labopin
2
, S. Giebel
3
, L. MiszyK
4
, G.
Loganadane
5
, M. Michallet
6
, G. Socié
7
, N. Schaap
8
, J.
Cornelissen
9
, I. Yakoub-Agha
10
, A. Nagler
11
1
Universite Paris Est Creteil, Radiation Oncology-
Hôpitaux Universitaires Henri Mondor- INSERM U955 Eq7,
Créteil, France
2
EBMT Paris study office, CEREST-TC- Paris- France.
Department of Hematology- Saint Antoine Hospital,
Paris, France
3
Maria Sklodowska-Curie Memorial Center Center and
Institute of Oncology-, Bone marrow transplantation and
Onco-hematology, Gliwice Branch, Poland
4
Maria Sklodowska-Curie Memorial Center and Institute
of Oncology, Radiation Oncology, Gliwice Branch, Poland
5
Universite Paris Est Creteil, Department of Radiation
Oncology- Hôpitaux Universitaires Henri Mondor, Créteil,