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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
__________________________________________________________________________________________
mentally stressing. The total waiting time consists of delay
before the referral to the specialist, delay from the
referral to the diagnosis, and then the delay before the
treatment.
Material and Methods
The Finnish national Head and Neck Oncology working
group has evaluated the waiting time of head and neck
cancer patients at the university hospital level bi-annually
starting 2012 and taking a two-month period annually. At
Turku University Hospital the waiting times were analysed
in more detail starting from the year 2013 by analysing all
the new patients referred to the tumour board meeting in
October and November each year.
Results
At national level the waiting time from the first referral
to the beginning of the treatment varied depending on the
treatment modality and also depending on the hospital. In
the latest analysed time period the waiting time varied
from 15 to 45 days for patients receiving surgical
treatment and from 31 to 83 days for those having
definitive oncological therapy. In general the waiting time
has slightly decreased from 2012 with a couple of
exceptions. During this period Turku University Hospital
has introduced a diagnostic package for head and neck
cancer patients and the waiting time has decreased
especially for the patients whose diagnosis was known at
the time of referral.
Conclusion
The data from the national follow-up study will be
presented. The presentation includes more detailed data
from Turku University Hospital including the system of
diagnostic package.
PO-064 Normal tissue complication probability model
for tube feeding dependence 6 months after
radiotherapy
N. Kanayama
1
, R.G.J. Kierkels
2
, R.J.H.M. Steenbakkers
2
,
A. Van der Schaaf
2
, M. Miyazaki
1
, T. Fujii
3
, K. Nishiyama
4
,
J.A. Langendijk
2
, T. Teshima
1
1
Osaka Medical Center for Cancer and Cardiovascular
Diseases, Department of Radiation Oncology, Osaka,
Japan
2
University of Groningen- University Medical Center
Groningen, Department of Radiation Oncology,
Groningen, The Netherlands
3
Osaka Medical Center for Cancer and Cardiovascular
Diseases, Department of Otolaryngology- Head and Neck
Surgery, Osaka, Japan
4
Yao Municipal Hospital, Department of Radiation
Oncology, Yao, Japan
Purpose or Objective
A multivariable normal tissue complication probability
(NTCP) model for tube feeding dependence 6 months after
radiotherapy (TUBEM6) was published in “Radiotherapy
and Oncology” 2014. The purpose of this study is to
externally validate the published NTCP model for TUBEM6
and to develop NTCP model for TUBEM6 of our institute.
Material and Methods
This study included 122 patients of pharyngeal or laryngeal
cancer treated by definitive intensity modulated
radiotherapy (IMRT). The median total dose was 69.96
Gy/33 fr and the median dose to elective area was 45
Gy/25 fr. One hundred and one (83%) patients received
chemoradiotherapy. We omitted level Ib, except in case
of deep invasion to the oral cavity or highly suspicious
lymph node for metastasis on level Ib. The organs at risk
relating to swallowing dysfunction (pharyngeal constrictor
muscle, cricopharyngeal inlet, supraglottic larynx, glottis
area, oral tongue and anterior oropharynx) were
contoured according to the consensus guideline published
in 2015. The external validity was assessed by the
calibration curve using the Hosmer-Lemeshow test. The
discriminative ability of the model was calculated using
the area under the curve (AUC) and the (pseudo) explained
variance was measured with the Nagelkerke’s R
2
. A
backward approach was used to select the most predictive
variables in the multivariable logistic regression analysis,
out of variables which were significant in the univariable
analysis.
Results
The prevalence of TUBEM6 was 5.7% in the cohort of our
institute. When we calculate by the published NTCP
model, the mean predicted value of TUBEM6 was 12.2%
(95% CI: 8.3%-16.0%). Using the published NTCP model,
Nagelkerke’s R
2
was 0.06. The AUC was 0.79 and the
Hosmer-Lemeshow chi
2
was 9.3 (
p
= 0.320). One hundred
and six (87 %) patients had bilateral level Ib omitted from
elective nodal area. The group where bilateral level Ib was
omitted (omitting level Ib group) had lower TUBEM6
compared with the group where level Ib was included in
the elective nodal area (including level Ib group; 3.8% vs.
18.8%,
p
= 0.043). In omitting level Ib group, there was
significant reduction in the mean dose to the oral tongue
compared with including level Ib group (35.3 Gy vs. 48.8
Gy,
p
< 0.001). In multivariable analysis, the most
predictive factors for TUBEM6 in our institute were the
mean dose to the supraglottic larynx, the contralateral
parotid, and the oral tongue. In the NTCP model of our
institute, Nagelkerke’s R
2
was 0.36. The AUC was 0.89 and
the Hosmer-Lemeshow chi
2
was 4.64 (
p
= 0.795). 95% CI
of the predicted value of TUBEM6 was 3.7%-7.7%.
Conclusion
The prevalence of TUBEM6 was lower than expected in the
published NTCP model. However, the discriminative
ability and calibration was good. The mean dose to the
supraglottic larynx, the contralateral parotid and the oral
tongue play important role in TUBEM6. Neck irradiation to
the elective nodal area without level Ib contributes to
lower TUBEM6.
PO-065 Survival outcomes in Unknown Primary with
nodal metastases and role of Radiation therapy
A. Srivastava
1
, R. Bhalavat
2
, M. Chandra
2
, V. Pareek
2
1
Jupiter Hospital, Radiation Oncology, Navi Mumbai, India
2
Jupiter Hospital, Radiation Oncology, Thane, India
Purpose or Objective
Unknown primary with neck nodal metastases forms a grey
area in oncology wherein the treatment options are
limited and the outcomes vary with the modality chosen
for the same. Unknown primaries especially in head and
neck carcinoma require thorough evaluation and radiation
therapy to the neck nodal metastases forms an important
treatment in the armamentarium available for better
survival outcomes. In our retrospective study at our
center, we evaluated and present the survival outcomes