ESTRO 36 Abstract Book

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S175 ESTRO 36
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Conclusion
Our findings strongly favor use of cisplatin in CRT
treatment of locally advanced p16+ OPC. Until results of
randomized trials evaluating cisplatin versus cetuximab
are available, off-trial use of C225 in this population as an
effort to reduce morbidity should be discouraged,
especially in patients with advanced tumor and nodal
stage disease. In cases where cisplatin is contraindicated,
the use of carboplatin as an alternative option may reduce
DF compared to C225. When C225 is used, altered
fractionation radiotherapy may be beneficial for LRC.
OC-0332 Impact of HPV on effect of chemotherapy in
SCCHN : results of the GORTEC 2007-01 randomized
trial
X. Sun1, Y. Tao2, A. Auperin3, C. Sire4, L. Martin5, C.
Khoury 6, P. Maingon7, E. Bardet8, M. Lapeyre 9, Y.
Pointreau10, N. Ollivier3, A. Cornely2, O. Casiraghi11, J.
Bourhis12
1 CHRU- Besançon and Hôpital du Nord Franche Comté-,
radiotherapy, Montbéliard, France
2 Institut Gustave Roussy, Radiation Oncology, Villejuif,
France
3 Institut Gustave Roussy, Biostatistics, Villejuif, France
4 CH de Bretagne Sud, radiotherapy, Lorient, France
5 Centre Le Conquerant, radiotherapy, Le Havre, France
6 Centre Saint Louis, radiotherapy, Toulon, France
7 Centre GF Leclerc, radiotherapy, Dijon, France
8 Centre Gauducheau, radiotherapy, Nantes, France
9 Centre Perrin, radiotherapy, Clermont, France
10 Jean Bernard centre - Victor Hugo clinic, radiotherapy,
Le Mans, France
11 Institut Gustave Roussy, Pathology, Villejuif, France
12 CHUV, radiation oncology, Lausanne, Switzerland
Purpose or Objective
Chemo-radiotherapy (CT/RT) and cetuximab-RT (cetux-
RT) were established as standard treatments in non-
operated locally advanced (LA) SCCHN. The GORTEC 2007-
01 randomized trial was restricted to patients (pts) with
no or limited nodal spread (N0-N2a and non palpable N2b).
The results showed that the addition of concomitant CT
with cetux-RT backbone markedly improved both PFS and
LRC (Bourhis et al ASCO 2016 ) with no significant benefit
on overall survival. The impact of p16 expression on the
treatment effect of these patients was not available at the
time of the first presentation.
Material and Methods
The 1:1 randomization between cetux-RT (arm A) and
cetux-CT/RT (arm B) was done by minimization on
centers, N and T stages. Cetuximab was given as a loading
dose of 400 mg/m2 followed by weekly 250 mg/m2 during
RT. RT total dose was 70 Gy (2 Gy/day, 5 days/week).
Concurrent CT was 3 cycles of carboplatin 70mg/m²/d +
5FU 600mg/m²/d, D1-4. About 2/3 of the patients had
oropharyngeal cancers (OPC) and HPV status was
determined in these patients using p16 expression as a
surrogate (immunohistochemistry). Smoking status was
also collected. Primary endpoint was progression free
survival (PFS).
Results
Between Feb 2008 and Feb 2014, 406 pts were randomized
with 265 (65%) OPC. The median follow-up was 4.4 years.
Overall, p16 was assessed in 236 OPC (89%) patients (115
pts in arm A and 121 in arm B), and p16+ was found in 21%
of each arm (24 patients in arm A and 25 arm B). 15 out
the 49 (31%) p16+ patients were non-smokers, while 5/187
(3%) p16- patients were non-smokers. A significant
improvement in PFS was found in p16+ compared to p16-
OPC (p= 0.0002). A significantly improved PFS was
observed with cetux-CT/RT (arm B) compared with cetux-
RT (arm A) in p16- OPC (HR: 0.63, 95% CI: 0.44 – 0.91) as
well as in p16+ (HR: 0.23, 95% CI: 0.07 – 0.73), and the
interaction between p16 and treatment modality was not
significant (p=0.13). For loco-regional control, a similar
effect was found in both p16- and p16+ OPC in favor of
arm B (HR= 0.33 [95%CI 0.19 – 0.56] and 0.16 [95%CI 0.02
– 1.36] respectively; interaction test p=0.51).
Conclusion
The large majority of OPC patients randomized in this trial
were p16- and smokers. The addition of concomitant
chemotherapy to cetux-RT markedly improved PFS and
LRC in patients with OPC regardless of p16 status.
OC-0333 Prognostic impact of HPV and smoking in RT
of oropharyngeal cancer: the MARCH-HPV project
P. Lassen1, B. Lacas2, A. Trotti3, B. Zackrisson4, Q.
Zhang5, J. Overgaard1, J.P. Pignon2, P. Blanchard6
1Aarhus University Hospital, Department of Experimental
Clinical Oncology, Aarhus C, Denmark
2Gustave-Roussy Paris-Saclay University Ligue Nationale
Contre le Cancer meta-analysis platform, Biostatistics
and Epidemiology Department, Villejuif, France
3Moffitt Cancer Center, Department of Radiation
Oncology, Tampa- Florida, USA
4Umeå University, Department of Radiation Sciences -
Oncology, Umeå, Sweden
5NRG Oncology Statistics and Data Management Center
formerly RTOG, NRG Oncology Statistics and Data
Management Center formerly RTOG, Philadelphia- PA,
USA
6Gustave-Roussy Paris-Saclay University, Radiotherapy
Department- INSERM-U1018-CESP, Villejuif, France
Purpose or Objective
HPV is a favorable prognostic factor in radiotherapy (RT)
of HNSCC but whether HPV is predictive of response to
altered fractionated RT remains controversial. We aimed
to assess the potential prognostic and predictive impact of
HPV in altered fractionated RT and moreover to evaluate
the combined prognostic impact of HPV and smoking.
Material and Methods
The MARCH-HPV project is based on the first update of the
Meta-Analysis of Radiotherapy in HNSCC (MARCH), which
included 33 trials and 11833 patients. HPV status was
determined according to p16 immunohistochemistry. The
HPV analysis was restricted to oropharyngeal cancer (OPC)
and performed using a Cox model stratified by trial and
adjusted on gender, age, T-stage, N-stage, type of RT
schedule, p16 (positive, negative) and smoking status
(never/former, current). The potential prognostic and
predictive effects of HPV-status were estimated for
progression-free survival (PFS) and overall survival (OS).
Moreover, the combined prognostic impact of HPV and
smoking were assessed for PFS and OS.
Results