82 Advances in hadrontherapy

82 Advances in hadrontherapy

$23 80 81 FAST ~KlrrRON RADIOTHKRAPY IN T I ~ UNITED STATICS: WEI]FJ~ HAV8 W E BHEN AND wlq~RIK AIISt WIE C.,OI~G? B O R O N N u u r g O N CAF]URE...

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FAST ~KlrrRON RADIOTHKRAPY IN T I ~ UNITED STATICS: WEI]FJ~ HAV8 W E BHEN AND wlq~RIK AIISt WIE C.,OI~G?

B O R O N N u u r g O N CAF]URE TIIERAFY (BNCT}

G.E. Lar~or¢ Ph.D., M.D., Department of Radia60a Onoology, Unive~ity of Washington Medical Ce~¢x, Box 356043, Seattle, WA, 98195-6043, U .q.A. In the 1970s and 1980s the Natioml Cancer Institute of the United States spent approximately $"/0M in studying tbc clinical ~ of fastn ~ m m radiothora~ in the tmatm~t of vatom haman malignities. Cooperative clinicaltrialsw c m conducted first under tl~ auspices of the Radiation Tlm'apy Oncokagy G r o ~ (RTOG) umng for the n a ~ part ~ t r e a u ~ t facilities that we~ originslly constructed for physics research purposes and later by t i t Neutron Therapy CoUaborati~ Working Grcop (NrCWG) using more sophisticated hospital-based treatment facilities. Reaul~ to date show ~ d loeal/mgional ~ for inoperable salD'ary gland tumors and locally-advanced ptoslal¢ cancers with there also being strong indicaLiona (not based on randomized studies) of imp~ovo:l ~nttol for lnopmable sarcomas of bc~c and soft tLssue. For sqoamons c,eal minors of tbe lung them may be improved survival based upon a stlbsct analysis of a randomized, clinical vial, For other mamf systems such as ~uarnous call minors of the head and neck. cervical cancer, bladdec cancer, esophageal canc~, glioblastoma multiformc, and pancreatic canoer was no improvement ow.r tl~ resales of omv~ational photon radiation. At the present firm governmental support for oow,ron studies h Limited to maintaining a data bas= of trrated pabe.~ in order to provide iaformation on late effects inch~in~, soo~d mtlignanc~. Patle~ being treated with neutrons are billed on a "fee for servlee" be~s just m for other fcDmmof medical t x r ~ e a L C~'cnt ~ inl~tcSts of the. n'a'n~iningatetmn insdttaions Jn the United States lie mainly in I/~ possible applicntioo of a boron aeutroo capture (BNC) boost to ~ a m m tlm effccdw.ae.ss of fast .etanm radiollam~ and perha~ e.xlr.ad its cliaical ..srLulmss.

WoUgangSauc~ein Unive~si~ts-S'trahlenklinik Essen, Germany

BNCT Is based on the high cross section of 10B to capture thermal neutrons producing an a petticle and a IJ--nucleus [10B(n,ct)TIj]. For a useful clinic-,d application, this high LET radiation which has a very low range of about [0 pm should be selectively produced in tumor cells, in the past, the mod-.dity filled due to the lack of appropriated drugs, the deficiency of neutron beams able to defivcr thermal neurrotts at depth and the mm-~xisten(.'e of properly guided clinical trials. Nowadays, 2 drugs arc available for clinical trials (BPA and BSH) which shows some accuumulation in tumors. Some reactors were rebuUt to produce high intensity epithermal neutrons beams, Trials following "good clinical practice" were starred in the LIS -qnd are ready to start in Europe. The European phase i trial intends to evaluate the maxim',d. toleramd dose in patients suffering for glioblastoma. Very complex beams axe applied, containing photons, fast nozrrons and a high amount of therma.I neutrons which will produce high I.ET components In the target [i.c. 14N(n,p)]4C and 10B(n,a)7Li]. The absorbed dose D as a macroscopic quantity being the basic p a r a m e t e r for prescribing, recording and reporting a r=tdiothet-,rpeutic procedure cannot be easily used. The concept of the European protocol is to report the applied dose by describing the absorbed dose of each dose c o m p o n e n t and by introducing a single "biologically weighted dose (Dwu)" the unit of which, is called

"WLP('triple U'}. This approach will be presented tn open the cliscu~don to come to a consensus about dose spocilication and recording and reporting OFdoe= in BNCT.

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82 ADVANCES IN HADRONTEIERAPY. U. Amaldi, CERN, Geneva, Switzerland The first part of the report will be devoted to a brief overview on the European strategies in the fight against tumours, in particular in the field of radiotherapy. In the second part the principal centrcs for hadrontherapy are described, which are at present operating all over the world. In the third part, the Italian Hadrontherapy Programme will be presented, which, financed by the TERA Foundation, by INFN and ISS, foresees three independent and yet coherent activities: (i) the construction of a big "National Centre for Oncological Hadrontherapy" (CNAO), with four rooms for proton treatment, one room for ion treatment and one room for irradiation with thermic neutrons; (ii) the design and construction of comparatively cheap "compact accelerators" for protontherapy centres; (iii) a multimedia information net (RITA) for the selection of patients, capable to connect the many associated centres to CNAO and to the protontherapy ccntrcs. Underway is at present the set-up of a Consortium among IRCCS, Hospitals and TERA, for the implementation of the CNAO in Milan, on some estates owned by the Policlinico. Special attention will be focused on compact accelerators; this is an activity which involves, beyond the TERA Foundation, the lstituto Superiore di SanitA and the ENEA.

PROTON RADIATION THERAPY IN ADULTS WITH L O W - G R A D E CHONDROSARCOMAS OF THE CRANIAL BASE

NJ Licbsch, LG Renard, M Krengli, JE Munzenridcr, EB Hug, HD Suit Massachusetts General Hospital, Boston, USA

Since 1974, 160 adultpatientswith low-grade chondrosarcomas of the cranial base have received postoperative high-dose fractionatcdconformal proton radiation therapy with curative intentat Massachusetts General Hospitaland Harvard Cyclotron Laboratory. The median prescribed dose was "I'D= 68.4 Gy in 38 fractions.The median follow-up is 30 months. The local tumor control = freedom from tumor progression is 97% at 5 and 10 years.None of the patientsdeveloped metastaticdisease. 8% of the patientshad serioustreatment-relatedcomplications. Management of low-grade chondrosarcomas of the cranialbase requires a carefullyplanned interdisciplinaryapproach: cranial base surgery with the aim of (I) establishing a reliabletissue diagnosis of the tumor and (2) improving the tumor geometry, i.e. removing those tumor components that significantly compromise neighboring critical anatomic structures, in combination with postoperativefractionatcdprecisionhigh-dose radiationtherapy.