We report the results of phase I/II studies of preoperative multidisci
plinary treatment of 14 patients with soft tissue sarcoma using hypert
hermia from November 1990 to April 1995. The preoperative treatment wa
s conducted with thermo-radio-chemotherapy in 11 cases of stage III, a
nd with thermo-radiotherapy as well as thermo-chemotherapy in three ca
ses of stages I and II. Hyperthermia was carried out twice a week with
totals ranging from 4 to 14 times (average: 8.4 times); each session
lasted 60 min. Radiotherapy was administered four or five times per we
ek, and the dose was 1.8-2Gy/fraction, with a total of 30-40 Gy in a f
our week period. Chemotherapy was mainly in the form of MAID regimen (
2-mercaptoethanesulphonic acid (mesna), adriamycin, ifosfamide and dac
arbazine). The tumors were surgically resected in all patients after c
ompleting the preoperative treatment. The efficacy rate, as expressed
by the percentage of either tumors in which reduction rate was 50% or
more, or tumors for which post-treatment contrast enhanced CT image re
vealed low density volumes occupying 50% or more of the total mass, wa
s 71% (ten of the 14 tumors). The mean tumor necrosis rate in the rese
cted specimens was 78%. The tumor necrosis rate was significantly high
(P <0.05) in patients whose Time greater than or equal to 42 degrees
C was of long duration. Postoperative complications were observed in s
ix patients; among these, two patients developed wound infection that
required surgical treatment as a complication of surgery performed in
the early stage following the preoperative treatment. After a mean pos
toperative follow-up of 27 months, distant metastasis occurred in four
patients resulting in three fatalities. The three-year cumulative sur
vival rate was 64.3%. No local recurrence was observed in any patient
during the follow-up, thus confirming our hypothesis that preoperative
multidisciplinary treatment has an excellent local efficacy. We think
that it would be valuable to conduct, at many facilities, phase III s
tudies on the treatment of soft tissue sarcoma by a combination of sur
gery and preoperative multidisciplinary treatment using hyperthermia,
paying close attention to the interval between these two modalities.