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6th ICHNO
6
th
ICHNO Conference
International Conference on innovative approaches in Head and Neck Oncology
16 – 18 March 2017
Barcelona, Spain
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was performed in general anaesthesia using systemic
bleomycin (15.000 IU/m
2
) prior to electroporation with
sequences of 8 pulses of 100µs and 1000 V/cm applied
voltage to electrode distance ratio. Evaluation of tumour
response was assessed from PET/CT-, MRI- scans and
biopsies. Primary objective was tumour response
measured using RECIST criteria. Secondary objectives
included tumour response in the treatment area from MRI
and multiple time point FDG PET scans as well as patient
evaluation of treatment using pain score and quality-of-
life questionnaires (EORTC QLQ-C30 and QLQ-H&N35).
Results
Nineteen patients were included in this ongoing trial and
treated for a recurrent carcinoma in the head and neck
area. Due to large tumours, treatment could in most cases
only be applied to parts of the tumour thereby leading to
a debulking. Thirteen patients were evaluable according
to RECIST criteria at evaluation 8 weeks after treatment.
One patient died before evaluation. Five patients had
cystic tumours at evaluation and therefore not evaluable
according to RECIST criteria. Overall response in the 13
patients evaluable by REICST was 62% (8 of 13 pts): of
these 2 (15%) had complete remission (CR), 6 (46%) had
partial remission (PR), while progression (PD) was
observed in 5 (39%). The MRI and PET results from the
treatment area are currently being assessed.
There was no change in pain score from baseline to
evaluation.
Quality-of-life
questionnaires
only
demonstrated a change in dysphagia.
Conclusion
Electrochemotherapy was feasible in patients with
recurrent head and neck cancer without further standard
treatment options. Overall response rate was 62% with
limited side effects, warranting continuation of the study.
PO-096 Dosimetric evalutation of volumetric modulated
arc therapy (VMAT) in sinonasal cancer raiotherapy
E. Donini
1
, S. Magi
2
, S. Ricci
2
, E. Pasquini
3
, G. Frezza
1
1
Ospedale Bellaria - AUSL Bologna, Radiotherapy,
Bologna, Italy
2
Ospedale Bellaria - AUSL Bologna, Medical Physics,
Bologna, Italy
3
AUSL Bologna, Ear- Nose and Throat Metropolitan Unit,
Bologna, Italy
Purpose or Objective
To assess dosimetric parameters of volumetric modulated
arc therapy (VMAT) for nasosinusal malignancies with
regard to the coverage of planning target volume (PTV)
and the sparing of organs at risk (OAR).
Material and Methods
Nine patients with naso sinusal malignancies were treated
with postoperative radiotherapy (VMAT, 2-3 non coplanar
arcs) between 2015 and 2016. Seven patients were
treated on primary target volume only (tumor bed), two
patients required also nodal irradiation. Planning goals
were the following: PTV: > 98% volume covered by >95%
of prescribed dose; >107% of prescribed dose to < 2% PTV
volume; for organs at risk (OARs): maximum doses
(D(max)) < 60 Gy to the brainstem, < 54 to the optic
chiasm, < 50 to the optic nerves, <40 Gy to the eyes and <
5 Gy to the lenses. Dose was prescribed to the median dose
according to ICRU 83. Dose-volume histogram, the
maximum, minimum, and mean doses to the target
volumes and organs at risk, and monitor units (MUs) were
evaluated.
Results
VMAT offered a good tumor volume coverage and provided
a good sparing of OARs (mean Dmax ipsilateral optic
nerve:45,8 Gy, mean Dmax contralateral optic nerve:
43,3; mean Dmax optic chiasm: 46,4 Gy; mean Dmax
brainstem: 37,9 Gy; mean Dmax ipsilateral eye: 47,6 Gy;
mean Dmax contralateral eye: 33,3 Gy). VMAT showed low
MUs (mean MUtot: 583,7) and low treatment delivery.
Conclusion
VMAT's plans further reduce doses to critical structures
that are in close proximity to the target volume, and
reducing treatment delivery time, decrease the effects of
intrafractional uncertainties that can occur because of
patient movement during treatment delivery.
Poster: Biology, HPV and molecular targeting
PO-097 Droplet Digital PCR for detection of circulating
tumour DNA in blood of head and neck cancer patients
J.H. Van Ginkel
1
, M.M.H. Huibers
1
, R.J.J. Van Es
2
, R. De
Bree
3
, S.M. Willems
1
1
UMC Utrecht, Pathology, Utrecht, The Netherlands
2
UMC Utrecht, Oral and Maxillofacial Surgery and Head
and Neck Surgical Oncology, Utrecht, The Netherlands
3
UMC Utrecht, Head and Neck Surgical Oncology, Utrecht,
The Netherlands
Purpose or Objective
During posttreatment surveillance of head and neck
cancer patients, imaging is insufficiently accurate for the
early detection of relapsing disease. Free circulating
tumor DNA (ctDNA) may serve as a novel biomarker for
monitoring tumor burden during posttreatment
surveillance of these patients. In this exploratory study,
we investigated whether low level ctDNA in plasma of
head and neck cancer patients can be detected using
droplet digital PCR (ddPCR).
Material and Methods
TP53
Mutations were determined in surgically resected
primary tumor samples from 6 patients with high stage (II-
IV), moderate to poorly differentiated head and neck
squamous cell carcinoma (HNSCC). Subsequently,
mutation specific ddPCR assays were designed.
Pretreatment plasma samples from these patients were
examined on the presence of ctDNA by ddPCR using the
mutation-specific assays. The ddPCR results were
evaluated alongside clinicopathological data.
Results
In all cases, plasma samples were found positive for
targeted
TP53
mutations in varying degrees (absolute
quantification of 4.2 – 422 mutational copies/ml).
Mutations were detected in wild-type
TP53
background
templates of 7,667 – 156,667 copies/ml, yielding
fractional abundances of down to 0.03%.
Conclusion
Our results show that detection of tumor specific
TP53
mutations in low level ctDNA from HNSCC patients using
ddPCR is technically feasible and provide ground for future
research on ctDNA quantification for the use of diagnostic
biomarkers in the posttreatment surveillance of HNSCC
patients.