ESTRO 36 Abstract Book

S152

ESTRO 36

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there is still some room for serendipity: an example of this

will presented with flash-RT.

Symposium: New paradigm in HNSCC

SP-0291 Modern biomarkers for therapeutic strategy:

radiation dose or volume modification

M. Krause

TU Dresden- Med. Faculty Carl Gustav Carus, Dresden,

Germany

Decisions on radiotherapy indication, dose or combined

treatments are today based on tumour stage and

localisation as well as surgical factors. Over the last years,

an increasing number of translational studies has shown

biological parameters that are associated with

locoregional tumour recurrences, metastases and/ or

patient survival. Most prominent and already in clinical

Intervention trials is Human Papillomavirus (HPV) subtype

16, which is present in a high percentage of head and neck

squamous cell carcinoma (HNSCC) and has been shown to

lead to radiosensitivity of tumours in preclinical as well as

in clinical studies. Other biomarkers like hypoxia related

markers or putative cancer stem cell markers are

expected to indicate a higher radioresistance of tumours.

Such biomarkers, after systematic validation in

independent datasets, may build a basis for interventional

trials with different radiation doses for different risk-

stratified patient groups.

Less data is currently available on biomarkers predicting

the efficacy of radiotherapy to different treatment

volumes, e.g. unilateral versus bilateral neck Irradiation

or selective inclusion of different lymphnode levels. Such

data are harder to generate as they need to base on

patient groups that have been treated using different

treatment volumes.

The talk will give an overview on current clinical evidence,

translational studies and promising biomarkers evaluated

within clinical Trials.

SP-0292 The changing role of head and neck surgeon

in HPV-positive oropharyngeal squamous cell

carcinoma, or do we still need surgery?

C. Simon

Centre Hospitalier Universitaire Vaudois, Lausanne

Vaud, Switzerland

HPV-positive oropharyngeal squamous cell carcinomas

(OPSCCs) are delineating a separate disease entity with an

overall better prognosis and different biology in

comparison to HPV-negative OPSCCs. The role of the

surgeon for this disease remains to be elucidated and

depends on the outcome of surgical trials, i.e the “Best-

of” EORTC 1420 trial, that is comparing IMRT with trans-

oral surgery in early-stage OPSCCs. Also for advanced-

stage disease trials are currently underway to better

define adjuvant treatment after surgery (PATHOS, ECOG

3311) or compare surgery-based treatments for operable

advanced OPSCCs with RT-strategies (ORATOR). It will

depend on the outcome of these trials, which role the

surgeon will play in the future in the treatment of HPV-

positive OPSCCs.

SP-0293 Radiation de-escalation strategies in HPV-

positive squamous cell carcinoma

J. Giralt

Hospital Universitario Vall d'Hebron, Barcelona, Spain

Human papillomavirus-related (HPV+) oropharyngeal

cancer is a rapidly emerging diseasein many countries that

differs from tobacco-related and alcohol-related (HPV–

)oropharyngeal cancer. HPV+ oropharyngeal carcinoma is

now established as a distinctbiological entity, being

prognosis significantly superior than HPV negative

tumor.Although their survival is excellent, standard RT-CT

regimens produce substantial

toxicity.In

that scenario

strategies for de-intensification have been

developed.De

intensification is to modify the standard treatment in

order to reduce the long-termtoxicities associated with

radiation / chemotherapy while maintaining the high cure

rates.Prognostic factors allow us to select patients with

excellent outcomes that can benefits from de-

intensification strategies. This factors are: Oropharyngeal

cancer, P16 +, minimalsmoking history, non bulky primary

and non-extensive nodal spread (not N2c-N3).Strategies

for de-intensification are: Select chemo responders and

reduce RT dose or thevolume, reduce RT dose and

cisplatin, replace cisplatin with cetuximab, use

TORSresection and reduce adjuvant RT dosePublished de-

escalation clinical trial will be presented and discussed as

well as the mostimportant ongoing

trials.As

conclusions:

radiation de-escalation is experimental and should be

conducted in clinicaltrials, appropriate candidates for de-

escalation are well defined, there are differentstrategies

for de-intensification, preliminary data show efficacy but

the effect on long-termtoxicity reduction need to be

proved.

Symposium with Proffered Papers: Costs and value of

radiotherapy innovations: how to assess

SP-0294 Health Technology Assessment: what’s in a

word?

A. Aggarwal

London School of Hygiene and Tropical Medicine, Health

Services Research and Policy, London, United Kingdom

Health Technology Assessments (HTA) aim to ensure

rational and fair decisions are made on resource allocation

for new health interventions. The advantage of HTAs are

their universality when making decisions regarding which

treatments across all medical specialities represent the

best value to society. However, few if any countries

internationally use HTA in the evaluation of radiation

technologies. Instead these processes have largely

focussed on new cancer drugs, informing reimbursement

policy for public health systems.

In the absence of HTA processes, low regulatory barriers

have resulted in the relentless diffusion of increasingly

expensive radiotherapy innovations which offer ever-

marginal gains in the therapeutic ratio. Without a rational

and evidence based approach to evaluation the costs of

delivering cancer care will continue to rise exponentially.

I will discuss how a commitment to HTA processes is

imperative in order to avoid many of the entrenched

interests and inefficient practices that have manifest in

high income countries due to differences in cancer care

delivery, and health system financing. I will also highlight

the challenges in establishing HTA for radiotherapy

interventions, given the diversity in innovation, and

limitations within the evidence base to enable

comparative effectiveness research.

In addition I will offer insights into the challenges of

implementing HTA decisions in practice, using the

experiences of the UK National Institute for Health and

Clinical Excellence (NICE) as an example. Specifically, the

impact of political, public and media pressure on HTA

assessments of cancer therapies as well as the negative

consequences of bypassing these value driven approaches

to reimbursement policy.