J.J. Broerse, Radiobiological Institute TNO, Rijswijk, The Netherlands,
and T .J. MacVittie, Armed Forces Radiobiology Research Institute,
Bethesda, MD, USA. During the past decade, relatively few new studies
have been initiated on the response of different species to high-dose,
total-body irradia- tion. For information on the LDSO/30d (the dose
which produces 50 percent lethality within 30 days), one is generally
referred to the older literature (e. g., Bond, Fliedner and Archambeau,
1965). Compari- son of experimental data reveals considerable variations
in LDSD values even after total-body irradiation with conventional X
rays, ranging from 4 to 6 Gy in the monkey, 7.1 to 9 Gy in the rat and
from 6.4 to 9 Gy in the mouse (see also Hall, 1978). Part of the
discrepancy in the LDso values can possibly be attributed to
inadequacies in the dosimetry procedures and exposure arrangements
employed. As far as clinical experience is concerned, there is now an
appreciable amount of information available about the effect of total-
body irradiation as a conditioning treatment for bone marrow transplan-
tation in patients suffering from leukaemia or aplastic anaemia. The
results from different centres, including the incidence of complications
such as radiation pneumonitis, are considerably different. This can part
I y be connected with the application of different radiation sched-
ules: large single dose versus fractionated or protracted irradiation.