430 / 1173
EQD
2
late
=
24 4
+
3
2
+
3
!
"
#
$
%
& =
33.6
Considering late injury, using
α/β
= 3
Gy,
Therefore, giving the rest of the treatment as
would give
equal late injury
as 35 × 2 Gy.
70 – 33.6
=
36.4
Gy
in 2 Gy fractions
In practice, 36.4 ÷ 2 ≈
18
(maybe 19) fractions.