186 / 1082
S173
ESTRO 36 2017
_______________________________________________________________________________________________
time to complete chemoradiation (CRT), and were more
likely to receive standard fractionation vs BID or
concomitant boost (see table). With a median follow-up
of 35.7 months, PBC improved 3yr locoregional control
(LRC) [91.6 vs 69.1%], distant metastasis-free survival
(DMFS) [88.9 vs 71.6%], and cause-specific survival (CSS)
[94.1 vs 80.0%] compared to C225 [all p<0.001— see A-C
on figure]. Median time to distant failure (DF) was shorter
for the C225 group (7.1 vs 17.2 months, p=0.006). On MVA
the use of C225 increased the risk of locoregional failure
(LRF) [HR 4.099, 95%CI 1.949-8.621, p<0.001], DF [HR
3.438, 95%CI 1.684-7.016, p=0.001], and cause-specific
mortality (CSM) [HR 4.076, 95%CI 1.894-8.771, p<0.001].
On subgroup analysis the use of carboplatin trended
toward decreased DF (p=0.100) compared to C225,
although the rates of LRF were similar. When including
only the C225 patients, UVA showed a strong trend toward
increased LRF associated with ≥T3 tumors [p=0.066] and
standard fractionation [p=0.100 — see D on figure 1];
additionally, advanced nodal stage (≥N2b-N3) predicted
for increased DF [p=0.029] and CSM [p=0.035]. On MVA of
this subgroup, standard fractionation [HR 2.994, p=0.09]
and ≥T3 tumors [HR 2.633, p=0.056] continued to trend
strongly in predicting for LRF as did advanced nodal stage
for DF [HR 5.917, p=0.064] and CSM [HR 6.586, p=0.077].
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. Sun
1
, Y. Tao
2
, A. Auperin
3
, C. Sire
4
, L. Martin
5
, C.
Khoury
6
, P. Maingon
7
, E. Bardet
8
, M. Lapeyre
9
, Y.
Pointreau
10
, N. Ollivier
3
, A. Cornely
2
, O. Casiraghi
11
, J.
Bourhis
12
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