Purpose: Hyperfractionated and accelerated radiotherapy without a split was
performed to improve the local control probability of early glottic carcin
omas. We analyzed the results of this regimen by using the Ki-67 index.
Methods and Materials: Over a 12-year period, 85 T1N0M0 glottic cancers and
50 T2N0M0 glottic cancers were treated with conventional fractionation (CF
) from 1984 to 1989 and with accelerated fractionation (AF) since 1990, The
CF program consisted of five daily fractions of 2 Gy per week, for a total
of 64 Gy, The AF program consisted of 1.72 Gy per fraction, two fractions
per day, 5 days a week, for a total of 55 or 58 Gy, The specimens, taken be
fore radiotherapy, were immunohistochemically stained with anti-Ki-67 antib
Results: The 5-year local control probability for T1 tumors was 79.6 +/- 6.
9% with CF treatment, whereas with AF it was 86.9 +/- 5.6%. For T2 tumors i
t was 62.7 +/- 12.2% with CF, whereas it was 74.7 +/- 7.8% with AF. The dif
ference between CF and AF did not reach the point of statistical significan
ce. However, when T1 tumors had a Ki-67 index lower than 50%, the local con
trol rate achieved with AF was significantly better than that with CF (p =
0.018). When the tumors had a Ki-67 index that was 50% or more, there was n
o difference in the local control rate between CF and AF, whether they were
T1 or T2, The peak mucosal reactions at the larynx and/or hypopharynx were
much more severe and appeared at smaller doses and earlier in AF than in C
F, The patients with AF showed no severe late complications.
Conclusions: AF could not obtain statistically significant improvement in l
ocal control probability of T1 or T2 glottic carcinomas. (C) 2000 Elsevier