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6th ICHNO
page 49
6
th
ICHNO Conference
International Conference on innovative approaches in Head and Neck Oncology
16 – 18 March 2017
Barcelona, Spain
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Pretreatment OPN levels were higher in patients with
advanced T stage compared with early stage (p=0.024).
There was no correlation between N stage and OPN
(p=0.58). Median plasma levels of OPN measured before
(67.9 ng/ml) and after (97.8 ng/ml) treatment differed
(p=0.0001). OPN levels before treatment were
significantly related to overall survival (OS) ratio in both,
univariate (p=0.019) and multivariate analysis
(0.001). Posttreatment OPN levels (97.8 ng/ml) were also
associated with survival time in univariate analysis
(p=0.04). Additionally, OPN after treatment was
significantly higher in patients with distant metastasis
(p=0.015).
Conclusion
High levels of OPN before therapy have been associated
with advanced stage and adverse prognosis. OPN after
therapy may play important role in the process of tumor
development and metastasis. OPN concentrations increase
during treatment may reflect acute mucosal reaction after
radiotherapy. Pretreatment OPN is an independent
prognostic determinant of survival.
PO-102 EGFR detection in saliva as an easy diagnostic
and prognostic tool in oral squamous cell cancer
C. Piazza
1
, A. Paderno
1
, L. Zanotti
2
, E. Bandiera
2
, F. Del
Bon
1
, C. Romani
2
, P. Perotti
1
, E. Bignotti
2
, N. Montalto
1
,
R. Morello
1
, F.E. Odicino
2
, P. Nicolai
1
, A. Ravaggi
2
1
University of Brescia, Otorhinolaryngology - Head and
Neck Surgery, Brescia, Italy
2
University of Brescia, "Angelo Nocivelli" Institute of
Molecular Medicine - Division of Gynecologic Oncology,
Brescia, Italy
Purpose or Objective
Epidermal growth factor receptor (EGFR) is a type I
transmembrane glycoprotein widely expressed on
epithelial cells and required for their development and
proliferation. The extracellular domain of EGFR can be
released by proteolytic cleavage and shed from tumor
cells surface, thus representing a potential tumor marker.
EGFRs have been frequently found to be overexpressed in
a wide variety of malignancies, including oral squamous
cell carcinoma (OSCC). Our objective was to assess the
EGFR diagnostic and prognostic values in OSCC,
investigating its expression in serum and saliva of a
homogeneous group of patients in comparison with that of
healthy subjects.
Material and Methods
Serum and saliva samples were collected from a cohort of
OSCC patients before surgery and a matched group of
healthy subjects. A written consent was obtained in all
cases. Serum EGFR concentration was determined by an
enzyme-linked immunosorbent assay (ELISA), according to
manufacturer’s instructions. Saliva EGFR concentration
was determined with a modified protocol of the same
immunoassay. Sixty-three naïve patients affected by OSCC
(cases) and 60 healthy individuals (controls) were included
in the study.
Results
Regarding serum EGFR levels, OSCC patients (mean, 47.6
ng/ml; range, 29.9-82.5) evidenced significantly lower
values (p<0.001) when compared with controls (mean,
53.7 ng/ml; range, 38.6-70.7). Conversely, salivary EGFR
concentrations were significantly higher (p=0.001) in OSCC
patients (mean, 8.2 ng/ml; range, 0.9-37.8) than in
controls (mean, 4.4 ng/ml; range, 0.6-20.6). Salivary EGFR
levels were also significantly related with tumor pT
classification (p=0.02). Considering 9.0 ng/ml (75°
percentile) as the cut-off, patients with higher values of
salivary EGFR had a worse prognosis in terms of disease
specific survival (p=0.017) (Fig. 1), even when limiting the
evaluation to pT4 tumors only (p=0.05).
Conclusion
Salivary EGFR can be considered a potential tumor marker
for OSCC detection, with both diagnostic and prognostic
values. Serum EGFR, on the other hand, was significantly
lower in patients but did not show any prognostic impact.
Determination of these markers requires a non-invasive
sampling procedure and is based on a low-cost technique.
PO-103 Oropharyngeal cancer patient-derived
xenografts: Characterization and radiosensitivity.
J. Lilja-Fischer
1
, B. Ulhøi
2
, J. Alsner
1
, P. Lassen
1
, V.
Nielsen
3
, J. Overgaard
1
1
Aarhus University Hospital, Department of Experimental
Clinical Oncology, Aarhus, Denmark
2
Aarhus University Hospital, Department of Pathology,
Aarhus, Denmark
3
Aarhus University Hospital, Department of
Otorhinolaryngology, Aarhus, Denmark
Purpose or Objective
Oropharyngeal squamous cell carcinoma (OPSCC) is now
the most common type of head and neck cancer. HPV,
tobacco smoking or a combination of the two are the
major etiologic factors.
After radiotherapy-based treatment, prognosis is superior
for patients with purely HPV-associated OPSCC compared
to patients with tobacco-associated HPV-negative disease.
As an explanation, it has been hypothesized that HPV-
associated tumors are more radiosensitive. Patients with
overlapping etiologies (i.e., both HPV and tobacco
smoking) appear to have an intermediate prognosis,
something that is currently unexplained.
Since OPSCC is heterogeneous in disease biology and
treatment sensitivity, further personalization of
treatment is needed, which is the focus of ongoing clinical
trials. However, adequate pre-clinical models and
biomarkers reflecting treatment sensitivity are lacking.
Purpose of this study was to create a number of patient-
derived xenografts (PDX) reflecting the heterogeneity of
OPSCC and compare the models with the corresponding
original human tumors. Also, we wished to determine if
the PDX model is suitable for radiotherapy research.
Material and Methods
Fresh tumor biopsies from patients with primary,
untreated OPSCC were implanted subcutaneously in
immunodeficient mice. PDX tumors were serially
transplanted and expanded, producing generations of PDX
tumors with identical origin.
Xenograft tumors and human originals were compared
using histology and immunohistochemistry for p16,
cytokeratin AE1/AE3 and CD45. To characterize
radiosensitivity, PDX tumors were subjected to low-dose
irradiation in a growth delay assay (4 - 8 Gy, single
fraction).