In 1984, when the CHART regime was devised, it was predicted that acute rea
ctions in skin and mucosae would be more severe but that there would be a c
onsiderable reduction of late effects in normal tissues. The findings from
the pilot study conducted from 1985 to 1990 and from the randomized trials,
which entered cases from 1990 to 1995, are reviewed. With CHART, it was fo
und that acute mucosal reactions were more severe but tolerable and recover
able. Unexpectedly, acute skin reactions were reduced rather than increased
. Late reactions in the central nervous system have led to a dose restricti
on of 40 Gy. Effects in other normal tissues were significantly reduced but
the sparing effect was less than that predicted. This can perhaps be expla
ined by a half-time of repair of sublethal injury in human tissues in exces
s of 4 h.