Purpose. Relatively few results are available in the literature about the radiation response of unresectable
sarcomas in relation to their histology. Therefore, an attempt was made to summarize the present situation. Materials and methods. This report is based on a review of the literature and the author's own experience. Adult-type
soft tissue sarcomas,
chondrosarcomas, and
chordomas were analyzed. Radioresponse was mainly associated with the degree of
tumor shrinkage, that is, objective responses. Histopathologic responses, that is, the degree of
necrosis, are only discussed in relation to
radiation treatment reports of
soft tissue sarcomas as a group. Results.
Radiation therapy alone leads to major responses in about 50% of lipo-, fibro-, leiomyo-, or
chondrosarcomas. The response rate is less than 50% in
malignant fibrous histiocytomas, synovial, neurogenic, and other rare
soft tissue sarcomas. The response rates may increase up to 75% through the addition of radiosensitizers such as halogenated
pyrimidines or
razoxane, or by the use of high-LET irradiation.
Angiosarcomas become clearly more responsive if biologicals, angiomodulating, and/or
tubulin affinic substances are given together with
radiation therapy.
Razoxane is able to increase the duration and quality of responses even in difficult-to-treat
tumors like
chondrosarcomas or
chordomas. Conclusions. The available data demonstrate that the radioresponsiveness of
sarcomas is very variable and dependent on histology, kind of radiation, and various concomitantly given drugs. The rate of complete sustained remissions by
radiation therapy alone or in combination with drugs is still far from satisfactory although progress has been made through the use of sensitizing agents.