every year nearly 3.2 million people in europe are diagnosed with some form of cancer , making it one of the major societal challenges .
radiotherapy ( rt ) is a highly potent and cost - effective treatment for tumours , and forms a central part , with surgery , of modern cancer therapy .
rt also plays an important role in symptom control and pain relief for incurable patients .
rt is by far the most cost - effective modality for cancer treatment , with the added advantage of conserving tissue function . in recent years
, there has been increasing evidence that rt with hadrons  such as protons and carbon ions  has the potential to increase the local control rate for many types of tumours , while improving the survival chances and quality of life of treated patients .
hadrons can overcome the limitations of x - ray beams since they deposit most of their energy at the end of their range , in the target .
such ions thus allow for a more appropriate radiation dose distribution , a lower total energy deposition in the body , and better placement of energy to destroy the cancer cells while sparing more of the surrounding healthy tissues .
the next step in rt is to exploit beams of ions heavier than protons , since they have additional properties that can be used in cancer therapy .
indeed light ions , like carbon ions , have unique physical properties and more favourable depth dose distributions than protons .
unlike x - rays and protons , light ions have a lower lateral diffusion and above all a superior radio - biological effectiveness ( rbe ) at the end of their range .
this means that they can produce severe damage to the tumour while sparing healthy tissues , and are less dependent than x - rays and protons on the presence of oxygen to produce cell death in cancers with low oxygen levels ( hypoxia ) .
hypoxic tumours in fact are known to be very resistant to x - rays . around 15% of the tumours requiring rt
can be defined as radio - resistant and could benefit from the use of high - linear energy transfer particles as carbon ions at lower energies . with cancer continuing to be an increasing health risk , europe faces the major challenge of training more competent researchers in the field of rt .
this need was of particular urgency in 2008 when partner started , since two pt facilities were becoming operational : the heidelberg ion therapy centre ( hit , germany ) , and the italian centro nazionale di adroterapia oncologica ( cnao ) in pavia .
in europe , during the financed life of partner , the first dual centres ( i.e. centres which use both proton and carbon - ion beams ) began treating patients , two proton therapy clinical facilities treated their first patients ( the rinecker proton therapy center ( rptc ) in munich , germany , and the proton therapy centre ( ptc ) in prague , czech republic ) , while construction began of dual facilities such as medaustron in wiener neustadt , austria , and the particle therapy center ( ptc ) in marburg , germany , and proton facilities such as the agenzia provinciale per la protonterapia ( atrep ) in trento , italy , and westdeutsches protonentherapiezentrum ( wpe ) in essen , germany .
the long - term plans for advanced accelerator systems in france , poland , the slovak republic , spain , sweden , switzerland and the uk have progressed considerably . the project offered research and training opportunities to 25 young biologists , engineers , physicians and physicists , and allowed them to actively develop modern techniques for treating cancer . for this purpose partner relied on cutting edge research and technology development , effective networking , and open access to national facilities , as well as providing training by specialists in the field .
partner was the first organic attempt of multidisciplinary training of scientists in this rapidly growing field at a pan - european level .
the unique properties of hadron beams raise new challenges for researchers and exciting training opportunities on novel applications .
there is an ever - increasing need for precision when treating cancers in moving organs or very sensitive organs such as the brain - stem .
not only is precision important for accurate delivery but also the dispersion of beam - energy before and after hitting the tumour area is critical for improving the treatment ( therapeutic ratio ) and the resulting outcome .
the principal objective of partner was to educate and train young researchers in ht for the future , and thus help to integrate and develop clinical , biological and technical knowledge .
the training network was inspired by the existing enlight network , a platform from which scientists and specialists in ht disciplines from more than 100 institutes of over 20 different european countries meet regularly and discuss innovations in the field [ 35 ] .
the scientific objectives of the partner training programme were achieved by carrying out the research activities illustrated in table 1 .
the work plan was divided into three main categories : clinical , biological and instrumentation .
each of the institutions in the proposed network already had a scientific programme in one or all of these areas .
partner concentrated on the development of new solutions as well as on the continuation of the existing scientific programmes . 

table 1.research activities hosted at partner 's institutesnetwork participant  researchers and projectscern , european organization for nuclear research , switzerland 
 1 researcher in simulation and dosimetry3 researchers in grid hadron therapy test bedfondazione cnao , italy 
 1 researcher in clinical studies1 researcher in epidemiology and patient selection1 researcher in image guided hadron therapy1 researcher in novel gantry designgsi , gesellschaft fr schwerionenforschung , germany 
 2 researchers in radiobiologyhit , heidelberg ion therapy , germany 
 1 researcher in clinical studies1 researcher in epidemiology and patient selection1 researcher in simulation and dosimetrykarolinska institutet , sweden 
 2 researchers in radiobiology1 researcher in pet prototype , in - situ monitoringebg medaustron , austria 
 2 researchers in treatment planninguniversity of surrey , uk 
 1 researcher in radiobiology1 researcher in treatment planningtera foundation , italy 
 1 researcher in in - situ monitoring1 researcher in novel accelerator studyion beam applications , belgium 
 1 researcher in treatment planningsiemens medical solutions , germany 
 1 researcher in simulation and dosimetry1 researcher in image guided hadron therapyassociated partnersetoile project , franceifimed project , spain research activities hosted at partner 's institutes 1 researcher in simulation and dosimetry 3 researchers in grid hadron therapy test bed 1 researcher in clinical studies 1 researcher in epidemiology and patient selection 1 researcher in image guided hadron therapy 1 researcher in novel gantry design 2 researchers in radiobiology 1 researcher in clinical studies 1 researcher in epidemiology and patient selection 1 researcher in simulation and dosimetry 2 researchers in radiobiology 1 researcher in pet prototype , in - situ monitoring 2 researchers in treatment planning 1 researcher in radiobiology 1 researcher in treatment planning 1 researcher in in - situ monitoring 1 researcher in novel accelerator study 1 researcher in treatment planning 1 researcher in simulation and dosimetry 1 researcher in image guided hadron therapy the ambitious scientific objectives achieved through partner are : 
 enhancement of clinical research by expanding the first cohort of european patients treated with common protocols;production of knowledge , through experiments and modelling , about the biological mechanisms and the molecular players that are involved in the response of healthy and tumour tissues to light ions , to better identify which tumours are suitable for proton and carbon ion therapy;use of the most recent developments in the field of e - health to provide a common system of clinical records able to be used by all the european facilities for the recruitment and the follow - up of the patients , including those from far - away hospitals of countries which do not yet have a hadron therapy centre;development of synergy and commonality of design for various proposed projects , in particular regarding the delivery system and the treatment planning system ( tps ) , so as to achieve better quality control while giving european industry a lead in the manufacture of crucial components of future hadron therapy facilities;development of a second generation of in - beam pet detectors , which can map more precisely the space distribution of the positron - emitting isotopes produced during patient treatment with carbon ions and proton beams , leading to improvement in the quality control of the treatment;study and design of carbon - ion rotating gantries  based on the experience obtained at hit with the only ion gantry currently in existence  affordable for other centres because of the lower cost and energy consumption;development of the european common demonstration platform , starting with the most advanced facilities , in particular hit in heidelberg , and cnao in pavia .
enhancement of clinical research by expanding the first cohort of european patients treated with common protocols ; production of knowledge , through experiments and modelling , about the biological mechanisms and the molecular players that are involved in the response of healthy and tumour tissues to light ions , to better identify which tumours are suitable for proton and carbon ion therapy ; use of the most recent developments in the field of e - health to provide a common system of clinical records able to be used by all the european facilities for the recruitment and the follow - up of the patients , including those from far - away hospitals of countries which do not yet have a hadron therapy centre ; development of synergy and commonality of design for various proposed projects , in particular regarding the delivery system and the treatment planning system ( tps ) , so as to achieve better quality control while giving european industry a lead in the manufacture of crucial components of future hadron therapy facilities ; development of a second generation of in - beam pet detectors , which can map more precisely the space distribution of the positron - emitting isotopes produced during patient treatment with carbon ions and proton beams , leading to improvement in the quality control of the treatment ; study and design of carbon - ion rotating gantries  based on the experience obtained at hit with the only ion gantry currently in existence  affordable for other centres because of the lower cost and energy consumption ; development of the european common demonstration platform , starting with the most advanced facilities , in particular hit in heidelberg , and cnao in pavia .
additional objectives that complemented the network are equally important , and can be summarized as follows : 
 transformation of the existing co - ordinated network , enlight , into a promoter of r&d and training programs;organization of courses and demonstrations for european clinicians and medical physicists;creation of bridges between academics and commercial enterprises while maintaining the uniqueness of each institution , thus avoiding antagonism and promoting complementarity and most of all : creation of long - term collaborations among the young researchers who will become the leading scientists of tomorrow 's ht .
transformation of the existing co - ordinated network , enlight , into a promoter of r&d and training programs ; organization of courses and demonstrations for european clinicians and medical physicists ; creation of bridges between academics and commercial enterprises while maintaining the uniqueness of each institution , thus avoiding antagonism and promoting complementarity and most of all : creation of long - term collaborations among the young researchers who will become the leading scientists of tomorrow 's ht .
it should be noted that such an extensive collaboration , incorporating as many scientific and technological aspects and as much expertise as enlight   does , and consequently partner does , is unique in the field of ht , not only in europe but worldwide .
europe is playing an emerging role in particle rt , which could put this geographic area in the leading position throughout the coming years .
institutions involved in the network share the responsibility this entails , and are putting considerable effort into designing the training programme .
the result has been to propose a series of activities complementing conventional phd programmes , including a balanced variety of courses ranging from more general courses through sectorial to subject - specific and hands - on training .
the innovation of the research programme was based on close interaction between the numerous and diverse research fields , being practised in parallel by clinical radiation oncologists , radiobiologists , medical physicists , accelerator and detector physicists , and engineers ( see fig .
the originality was in the intrinsic translational character of all the research programmes , which were conceived in such a way as to bring benefits to the cancer patients .
some of the original publications resulting from the research performed in the framework of the project are following in this special issue dedicated to partner .
the unique properties of hadron beams raise new challenges for researchers and exciting training opportunities on novel applications .
there is an ever - increasing need for precision when treating cancers in moving organs or very sensitive organs such as the brain - stem .
not only is precision important for accurate delivery but also the dispersion of beam - energy before and after hitting the tumour area is critical for improving the treatment ( therapeutic ratio ) and the resulting outcome .
the principal objective of partner was to educate and train young researchers in ht for the future , and thus help to integrate and develop clinical , biological and technical knowledge .
the training network was inspired by the existing enlight network , a platform from which scientists and specialists in ht disciplines from more than 100 institutes of over 20 different european countries meet regularly and discuss innovations in the field [ 35 ] .
the scientific objectives of the partner training programme were achieved by carrying out the research activities illustrated in table 1 .
the work plan was divided into three main categories : clinical , biological and instrumentation .
each of the institutions in the proposed network already had a scientific programme in one or all of these areas .
partner concentrated on the development of new solutions as well as on the continuation of the existing scientific programmes . 

table 1.research activities hosted at partner 's institutesnetwork participant  researchers and projectscern , european organization for nuclear research , switzerland 
 1 researcher in simulation and dosimetry3 researchers in grid hadron therapy test bedfondazione cnao , italy 
 1 researcher in clinical studies1 researcher in epidemiology and patient selection1 researcher in image guided hadron therapy1 researcher in novel gantry designgsi , gesellschaft fr schwerionenforschung , germany 
 2 researchers in radiobiologyhit , heidelberg ion therapy , germany 
 1 researcher in clinical studies1 researcher in epidemiology and patient selection1 researcher in simulation and dosimetrykarolinska institutet , sweden 
 2 researchers in radiobiology1 researcher in pet prototype , in - situ monitoringebg medaustron , austria 
 2 researchers in treatment planninguniversity of surrey , uk 
 1 researcher in radiobiology1 researcher in treatment planningtera foundation , italy 
 1 researcher in in - situ monitoring1 researcher in novel accelerator studyion beam applications , belgium 
 1 researcher in treatment planningsiemens medical solutions , germany 
 1 researcher in simulation and dosimetry1 researcher in image guided hadron therapyassociated partnersetoile project , franceifimed project , spain research activities hosted at partner 's institutes 1 researcher in simulation and dosimetry 3 researchers in grid hadron therapy test bed 1 researcher in clinical studies 1 researcher in epidemiology and patient selection 1 researcher in image guided hadron therapy 1 researcher in novel gantry design 2 researchers in radiobiology 1 researcher in clinical studies 1 researcher in epidemiology and patient selection 1 researcher in simulation and dosimetry 2 researchers in radiobiology 1 researcher in pet prototype , in - situ monitoring 2 researchers in treatment planning 1 researcher in radiobiology 1 researcher in treatment planning 1 researcher in in - situ monitoring 1 researcher in novel accelerator study 1 researcher in treatment planning 1 researcher in simulation and dosimetry 1 researcher in image guided hadron therapy the ambitious scientific objectives achieved through partner are : 
 enhancement of clinical research by expanding the first cohort of european patients treated with common protocols;production of knowledge , through experiments and modelling , about the biological mechanisms and the molecular players that are involved in the response of healthy and tumour tissues to light ions , to better identify which tumours are suitable for proton and carbon ion therapy;use of the most recent developments in the field of e - health to provide a common system of clinical records able to be used by all the european facilities for the recruitment and the follow - up of the patients , including those from far - away hospitals of countries which do not yet have a hadron therapy centre;development of synergy and commonality of design for various proposed projects , in particular regarding the delivery system and the treatment planning system ( tps ) , so as to achieve better quality control while giving european industry a lead in the manufacture of crucial components of future hadron therapy facilities;development of a second generation of in - beam pet detectors , which can map more precisely the space distribution of the positron - emitting isotopes produced during patient treatment with carbon ions and proton beams , leading to improvement in the quality control of the treatment;study and design of carbon - ion rotating gantries  based on the experience obtained at hit with the only ion gantry currently in existence  affordable for other centres because of the lower cost and energy consumption;development of the european common demonstration platform , starting with the most advanced facilities , in particular hit in heidelberg , and cnao in pavia .
enhancement of clinical research by expanding the first cohort of european patients treated with common protocols ; production of knowledge , through experiments and modelling , about the biological mechanisms and the molecular players that are involved in the response of healthy and tumour tissues to light ions , to better identify which tumours are suitable for proton and carbon ion therapy ; use of the most recent developments in the field of e - health to provide a common system of clinical records able to be used by all the european facilities for the recruitment and the follow - up of the patients , including those from far - away hospitals of countries which do not yet have a hadron therapy centre ; development of synergy and commonality of design for various proposed projects , in particular regarding the delivery system and the treatment planning system ( tps ) , so as to achieve better quality control while giving european industry a lead in the manufacture of crucial components of future hadron therapy facilities ; development of a second generation of in - beam pet detectors , which can map more precisely the space distribution of the positron - emitting isotopes produced during patient treatment with carbon ions and proton beams , leading to improvement in the quality control of the treatment ; study and design of carbon - ion rotating gantries  based on the experience obtained at hit with the only ion gantry currently in existence  affordable for other centres because of the lower cost and energy consumption ; development of the european common demonstration platform , starting with the most advanced facilities , in particular hit in heidelberg , and cnao in pavia .
additional objectives that complemented the network are equally important , and can be summarized as follows : 
 transformation of the existing co - ordinated network , enlight , into a promoter of r&d and training programs;organization of courses and demonstrations for european clinicians and medical physicists;creation of bridges between academics and commercial enterprises while maintaining the uniqueness of each institution , thus avoiding antagonism and promoting complementarity and most of all : creation of long - term collaborations among the young researchers who will become the leading scientists of tomorrow 's ht .
transformation of the existing co - ordinated network , enlight , into a promoter of r&d and training programs ; organization of courses and demonstrations for european clinicians and medical physicists ; creation of bridges between academics and commercial enterprises while maintaining the uniqueness of each institution , thus avoiding antagonism and promoting complementarity and most of all : creation of long - term collaborations among the young researchers who will become the leading scientists of tomorrow 's ht .
it should be noted that such an extensive collaboration , incorporating as many scientific and technological aspects and as much expertise as enlight   does , and consequently partner does , is unique in the field of ht , not only in europe but worldwide .
europe is playing an emerging role in particle rt , which could put this geographic area in the leading position throughout the coming years .
institutions involved in the network share the responsibility this entails , and are putting considerable effort into designing the training programme .
the result has been to propose a series of activities complementing conventional phd programmes , including a balanced variety of courses ranging from more general courses through sectorial to subject - specific and hands - on training .
the innovation of the research programme was based on close interaction between the numerous and diverse research fields , being practised in parallel by clinical radiation oncologists , radiobiologists , medical physicists , accelerator and detector physicists , and engineers ( see fig .
the originality was in the intrinsic translational character of all the research programmes , which were conceived in such a way as to bring benefits to the cancer patients .
some of the original publications resulting from the research performed in the framework of the project are following in this special issue dedicated to partner .
the partner network provided important outcomes in various aspects : it contributed to important scientific results , it provided valuable and much needed education , and it guaranteed the training of the quality personnel necessary for the new centres .
the partner collaborators made important and crucial contributions to all scientific fields in cancer rt .
these significant advances are resulting in optimization of the ht that will be used in the years to come . in parallel ,
the network offered a unique opportunity to learn and to solve problems that are of paramount importance to the understanding of the medical use of ionizing radiation .
young researchers , normally specialized and trained in specific backgrounds , learned from clinicians , physicists and engineers how to work , interact and collaborate with a multidisciplinary team and to communicate effectively at all levels . finally , the very specific goal of partner was to perform r&d and to train relevant personnel for the various european centres and existing facilities ( heidelberg , pavia , gsi , cern , karolinska and the uk micro - beam facility ) , in such a manner that the patients will be able to be treated with optimal efficiency and without delay as the new centres become operational .
the goal of providing new and experienced personnel to ht centres was successfully achieved even before the conclusion of the project , when the first researchers were recruited as staff of existing and soon - to - become operational facilities .
the existing ht centres in europe are running on less than maximal capacity ( both with respect to clinical services and r&d ) and they need to increase patient throughput .
many of the facilities are limited by manpower , and recruitment is not easy due to the limited availability of experienced / trained personnel .
industries in ht are also limited in their capacity for delivery and installation , mainly due to restricted manpower .
partner has been a successful initiative that has provided a considerable number of researchers in the field , however the 25 trainees of the first programme alone can not solve the current problem .
the experience gathered through partner should be utilized and become a benchmark for future similar initiatives .
this work was supported by the european community 's seventh framework programme [ fp7/2007/-2013 ] under grant agreement no .
 partner ( particle training network for european radiotherapy ) is a project funded by the european commission 's marie curie - itn funding scheme through the enlight platform for 5.6 million euro . 
 partner has brought together academic institutes , research centres and leading european companies , focusing in particular on a specialized radiotherapy ( rt ) called hadron therapy ( ht ) , interchangeably referred to as particle therapy ( pt ) . 
 the ultimate goal of ht is to deliver more effective treatment to cancer patients leading to major improvement in the health of citizens . in europe , 
 several hundred million euro have been invested , since the beginning of this century , in pt . in this decade , the use of ht is rapidly growing across europe , and there is an urgent need for qualified researchers from a range of disciplines to work on its translational research . in response to this need , the european community of ht , and in particular 10 leading academic institutes , research centres , companies and small and medium - sized enterprises , joined together to form the partner consortium . 
 all partners have international reputations in the diverse but complementary fields associated with pt : clinical , radiobiological and technological . 
 thus the network incorporates a unique set of competencies , expertise , infrastructures and training possibilities . 
 this paper describes the status and needs of pt research in europe , the importance of and challenges associated with the creation of a training network , the objectives , the initial results , and the expected long - term benefits of the partner initiative . 
INTRODUCTION
Overall objectives
Development and implementation of the scientific programme
RESULTS
CONCLUSION AND OUTLOOK
FUNDING