ESTRO 36 Abstract Book

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S311 ESTRO 36 2017
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Poster: Clinical track: Head and Neck
PO-0603 Metachronous Second Primary Head and Neck
Squamous Cell Carcinoma
S.Y. Wu1
1 Taipei Medical University Hospital, No.111- Section 3
Department of Radiation Oncology, Taipei, Chinese
Taipei
Purpose or Objective
The optimal therapeutic decisions for metachronous
second primary head and neck squamous cell carcinomas
(mspHNSCCs) are unclear. We examined the treatment
outcomes of a national cohort to determine suitable
treatments and prognostic factors in patients with
mspHNSCCs at different stages and sites.
Material and Methods
We analyzed data of >20-year-old patients with HNSCC at
American Joint Committee on Cancer clinical stages I–IV
without metastasis collected from Taiwan Cancer Registry
databases. Our protocols were reviewed and approved by
the institutional review board at Taipei Medical University
( TMU-JIRB No. 201402018). The patients were categorized
into four groups based on the treatment modality: Group
1 (control arm, chemotherapy [CT] alone), Group 2
(reirradiation [re-RT] alone with intensity modulation
radiotherapy [IMRT]), Group 3 (concurrent
chemoradiotherapy [CCRT] alone [irradiation with IMRT]),
and Group 4 (salvage surgery with or without RT or CT)
Results
We enrolled 31 762 HNSCC patients without mspHNSCCs
and 1741 mspHNSCCs patients without distant metastasis .
Univariate and multivariate Cox regression analyses
revealed that surgery, CCRT, Charlson comorbidity index
(CCI) ≥6, stage of second HNSCC, stage of first HNSCC, and
duration from first primary HNSCC of >3 years were
significant independent prognostic risk factors for overall
survival. After adjustment, adjusted hazard ratios (aHRs;
95% confidence intervals [CIs]) for overall mortality at
mspHNSCCs clinical stages I and II were 0.91 (0.42-01.98,
P = .806), 1.34 (0.78-2.29, P = .284), and 0.60 (0.38-0.96,
P = .033) in Groups 2, 3, and 4, respectively; those for
overall mortality at mspHNSCCs clinical stages III and IV
were 0.72 (0.40-1.82, P = .255), 0.52 (0.35-0.75, P < .001),
and 0.32 (0.22-0.45, P < .001) in Groups 2, 3, and 4,
respectively. A Cox regression analysis indicated that a re-
RT dose of ≥6000 cGy was an independent protective
prognostic factor for treatment modalities.
Conclusion
Salvage surgery is recommended for mspHNSCCs if a
patient is operable. However, if the patient is inoperable,
CCRT is recommended rather than re-RT or CT alone. A re-
RT dose of ≥6000 cGy may be necessary for mspHNSCCs.
PO-0604 A PET-based nomogram to predict survival in
oropharyngeal cancers radiotherapy
J. Castelli1, A. Depeursinge2, V. Ndoh1, J.O. Prior3, M.
Ozsahin4, A. Devillers5, E. Chajon1, R. De Crevoisier 1, N.
Scher4, F. Jegoux6, E. Vauleon7, B. De Bari 4, J. Bourhis 4
1 Centre Eugène Marquis, Radiation Oncology, Rennes
CEDEX, France
2 University of Applied Sciences Western Switzerland,
University of Applied Sciences Western Switzerland,
Sierre, Switzerland
3 CHUV, Nuclear Medicine and Molecular Imaging
Department, Lausanne, Switzerland
4 CHUV, Radiation Oncology, Lausanne, Switzerland
5 Centre Eugène Marquis, Nuclear Medicine and Molecular
Imaging Department, Rennes CEDEX, France
6 CHU Rennes, Head and Neck department, Rennes,
France
7 Centre Eugène Marquis, Oncology, Rennes CEDEX,
France
Purpose or Objective
Purpose: In locally advanced oropharyngeal cancer (LAOC)
treated with definitive radiotherapy (RT), the aims of this
study were: (1) to identify PET-FDG parameters correlated
with overall survival from a first training patients and
therefore to compute a prognostic score; and (2) to
validate this scoring system in a second independent
cohort of patients.
Material and Methods
A training cohort including 76 consecutive LAOC patients
treated with chemoradiotherapy or with cetuximab in a
first Cancer Center were analyzed. A predictive model of
loco-regional control (LRC) and overall survival (OS) was
built based on PET-FDG parameters. After internal
calibration and validation of the model, a nomogram and
a scoring system were developed, and tested in a
validation cohort of 46 consecutive patients treated in a
second Cancer Center.
Results
The two populations differed notably concerning age
(mean 59.2 vs 63.3 years [p = 0.02]) the tumor volume
(GTV: 45.8 cm3 vs 25.6 cm3 [p <0.001]), p16 status (p16+:
18% vs 37%, [p = 0.001]) for the training and validation
cohort, respectively. The median follow-up for the
training cohort and validation cohort were 38 (range, 2-
80) and 23 months (range, 3- 57 months), respectively
(p<0.001). The 2-year OS rate was 58% (95% CI: 46-70%)
and 85% [74-99%] for the training and the validation
cohort, respectively (p=0.001). In multivariate analysis,
the metabolic tumor volume (MTV) of the primary tumor
and the lymph nodes were independent predictive factors
for LRC and OS. Internal calibration showed a very good
adjustment between the predicted OS and the observed
OS at 24 months. A prognostic score was calculated, based
on the β-parameter from the Cox model. A normalization
was applied to obtained a score ranging from 0- 5. Using
the predictive score, two risk groups (cut-off = 1.33) were
identified (median OS 42 vs 14 months, p<0.001) and
confirmed in the validation cohort (median OS not reached
vs 26 months, p=0.008) (Figure).
Conclusion
Conclusions: This is the first report of a PET-based
nomogram in oropharyngeal cancer. Interestingly, it
appeared stronger than the classical prognostic factors
and was validated in independent cohorts markedly
diverging in many aspects, which suggests that the
observed signal was robust.
PO-0605 Factors associated with late dysphagia and
xerostomia in (chemo)radiation for head and neck
cancer.
F. Duprez1, L. De Witte2, S. Nuyts3, S. Deheneffe4, D. Van
Gestel 5, M. Voordeckers6, H. Thierens2, W. De Neve7, K.
De Ruyck2
1University Hospital Ghent, Radiation Oncology, Gent,
Belgium
2Ghent University, Basic Medical Sciences - Medical
Physics, Ghent, Belgium