Memo to H Amols, Et Al, Subject: Notes on Meeting, February 15, 1977

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A general pion biomedicalmeeting warn held a t 11 a.m. on February 15, Oncology Studies, of which he is a member, has established a particle therapy committee chaired by Dt. Herman S u i t of Worrnachwetts General, which is conaidering 8 proposal tothe National Cancer Institute to reco-nd $400 million for lOIyear funding for national particle therapy studies. persona on the CROS favor neutron studies only, as they feel that plo lu are limited t o an oxygen enhancement advantage, and that neutrons have a lower OEB than pions. tohis group, chaired by Dr. Max hone,to recoasider data concerning pions, heavy ions, and protons. A meeting of the CROS w i l l be held on Feburary 2425 in Betheoda, and will be followed by a two-day meeting of Dr. Boone'o group, a t which time Dr. KligerPron and Dr. Yuhas will present pion biological gives evidence that pion0 have advantages other than a change inthe OER. He said he would ask Dr. Yuhae t o present his data t o the UNH/LASL group next week before he goes t o Bethesdo. Dr. KligerPan told the group that the national Cond tte e on Radiation Dr. Kligetm~ns aidDr. Yuhaa will be presenting data tothe group which Dr. Kligerman said he had received from the NCX a copy of the critique of the renewal application for clinical otudiea of pion radiotherapy (CA-16127). He said that the report was favorable and adequate funding warn rec ded by the review groups, although the NCI staff has requested that the budget be cut substantially because of a shortage of available funding for radiation studies. He also noted that renewal was approved for two years, rather than the three requested, so that the termination vould coincide with that for the pre clinical grant (CA-14052) and the two could be coalesced intoa single grant after that time. critique to each program chief for then t o review with their staff. H e said he was sending pertinent extracts of the Dr. Kligerman posed a question as t o whether the combined biological effects of high, medium, and low LET radiotion within a given microscopic volume might be greater than would be expected for high LET alone. noted that probability of cell kill is a function of physical dose. Dr. Kligerman said he feels something additional may be occurring which would better correlate the clinical, biological, and microdosimetric results. The group pointed out some problem and discussed aspects of the physlcal interactions that needed t o be considered, e.g., ionization density per unit time, spatial distribution of ionizations. ionization density along particle tracks, relationship of density t o physical dose, and relationship of density of ionization to subcellular recovery.

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ware zulv be- mde; Dr. Dicello noted that they were made in 8 2-alcron cube. DNA molecule (50-60 angstroms) vould be ideal. firm8d by Dr. Yuha8, who maid that any attempt tomas urea smaller volume would be du lr able, even if the group couldn't get dom tothe 50-60 .ngstrom working for 10 yams 011 rur u ren ents of such a small size, urd there are no meaoura a volume am ull as 250 angst rou. help, par it cula rly since Dr. Yuhae' doe. response data indic8teo inhibition of DNA repair with PIOM. Dr. Kligemaa said h. felt8 volume equivalent t o the approximte rize of a.. Dr. Di cello mid that Dr. Harold Roesi of Columbia Univerrity ha8 been He did note, however, that he mlght be able t o Dr. Kligerman said that would The pomsibility of accepting patients with other than head aad neck o r subcutaneous lesions v u 8ddressed. and Drn. Kelsey and Smith noted that beams are now available for penetration of 11, 15, 21, and 25 em. Dr. K liger ~ n said he would see If some appropriate pelvic cases mlght be available for the coming run, since head and neck cases are difficult to access. The meeting was 8djourned a t noon. A meeting will be scheduled for next week ata time when Dr. Yuhrs can make his presentation t o the group.