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A METHOD OF CURATIVE THERMORADIOTHERAPY
IN SUPERFICIAL TUMORS,
BREAST, HEAD AND NECK AND PROSTATE
James I. Bicher, M.D. and RALPH S. WOLFSTEIN, M.D.
Valley Cancer Institute, Los Angeles,
California U.S.A.
Objectives:
Hyperthermia increases the response of malignant tumors to radiation
therapy in experimental animals and clinical treatment. In our
experience, first in re-treatment of previously radiated fields that
necessitated the use of low dose radiation fractions as adjunct to the
heat treatments, and then progressively “de novo” and eventually with
curative intent, treatment protocols have been devised and tested that
yield positive preliminary data showing superior tumor response rates
and less side effects when compared with historical controls at our
institute. Based on these results and an increasing world literature we
undertook to treat with curative intent superficial heatable tumors of
the breast, prostate and head neck regions in patients that had refused
conventional cancer therapy.
Methods:
The hyperthermia part of the protocol extends the number of heat
treatments to correspond to the number of radiation-fractions. The
number of hyperthermia treatments therefore varies from 25-50 per course
for each treated field. The radiation protocol consists of progressively
decreasing daily doses of radiation therapy. Typically the treatment is
started at a daily dose of 180 cGy gradually reduced to 100 cGy
protracting a typical radiation therapy treatment course from 5000 cGy
in five weeks to 5000 cGy given in over eight weeks; or 7000 cGy in
seven weeks to 7000 cGy in 14 weeks. According to the ELLIS TDF formula,
this results in a 15% or 25% reduction of the effective radiation dose.
The total dose is adapted to the clinical situation. To this effect,
the use of objective end result parameters is introduced, including MRI,
MR Spectroscopy, PET Scanning and Tumor Marker levels. Treatment is
continued until these parameters revert to normal. Forty breast
patients, 27 head and neck and 18 prostate patients were treated with a
follow up period of two to five years. All patients were early stage
(less than III).
Results:
Breast patients showed an
82% complete response rate, head and neck patients 88% complete response
rate and prostate patients 93% complete response rate. Projected 5 year
survival rates were 80% for breast patients, 88% for head and neck, and
87% for prostate patients.
Conclusion:
Protracted hyperfractionation of daily thermoradiotherapy
1 Decreases the radiation dose
by 15 to 25%;
2 Decreases the side effects
of radiation therapy;
3 Allows treating to effect
using objective end point parameters (tumor markers, PET scans, MRI,
etc.);
4 Accomplishes a high
percentage of complete responses in superficial tumors;
5 Accomplishes a high 5-year
survival rate in the 80-90% range in early superficial tumors;
Keywords:
Cancer, head and neck, breast, prostate, hyperthermia, radiation,
survival.
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The Radiological Society of North
America 
