SAN ANTONIOAccelerated radiation therapy given concomitantly
with mitomycin C (Mutamycin) produced significantly improved results
over standard radiation in patients with advanced head and neck
cancer, Werner H. Dobrowsky, MD, reported at the at 41st Annual
Scientific Meeting of the American Society for Therapeutic Radiology
Large, hypoxic tumors appeared to receive the most benefit from the
addition of mitomycin. Thus, mitomycin might overcome some of
the problems due to hypoxia in head and neck cancers, said Dr.
Dobrowsky, of the Department of Radiotherapy and Radiobiology,
University of Vienna.
The study included 229 patients, predominantly male (median age, 56),
with squamous cell cancer of the head and neck region. Most had very
advanced disease. Most patients had actually been considered
inoperable by the referring surgeons. About 85% had T3/T4 tumors, and
almost 80% had lymph node metastasis, he said.
This three-arm randomized trial was conducted between October 1990
and December 1997, and consisted of the following groups:
A conventional fractionation arm receiving 70 Gy in 35 fractions over
An accelerated fractionation arm receiving 2.5 Gy on day 1 and two
fractions of 1.65 Gy at least 6 hours apart on days 2 to 17, for a
total dose of 55.3 Gy.
An accelerated fractionation arm as above with the addition of
mitomycin given on day 5 at a dose of 20 mg/m².
The results with standard radiotherapy alone were comparable to those
with hyperfractionated accelerated radiotherapy alone. So we
can conclude that 70 Gy in 7 weeks is comparable to 55.3 Gy in 17
consecutive days. That is, you can save some dose by shortening
treatment time, Dr. Dobrowsky said.
Both local tumor control and survival were significantly improved in
patients treated with combined accelerated radiotherapy and mitomycin
Local tumor control was 31% after standard radiation, 34% after
accelerated radiation, and 48% following accelerated radiation
administered concomitantly with mitomycin. Two-year survival was 27%
with standard radiation, 28% with accelerated radiation, and 39% with
accelerated radiation administered concomitantly with mitomycin.
All patients developed mucositis at the end of the second treatment
week, with marked toxicity, especially in those patients treated with
accelerated fractionation, with and without mitomycin, Dr. Dobrowsky
reported, but the total duration of the mucositis did not differ
among the three treatment groups.
Dr. Dobrowsky and his colleagues concluded that the addition of
mitomycin to the accelerated radiation therapy regimen improved
results significantly with regard to local tumor control and to
actuarial overall survival. From our results, we also conclude
that hypoxia is a major factor for local failure, and this can, in
part, be overcome by administration of mitomycin, which is more toxic
to hypoxic cells, he said.