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Postirradiation sarcomas of the head and neck.

We discuss four cases of postirradiation sarcomas of the head and neck. Two cases were metachronous sarcomas that appeared after operation and irradiation for primary sarcomas, 1 case was a mandibular malignant fibrous histiocytoma that developed on the opposite side of the jaw from a malignant histiocytic neoplasm that was irradiated 8 years previously, and 1 case was a laryngeal tumor that appeared 5 years after combined operative and radiation therapy for a laryngeal squamous carcinoma. Immunohistochemical studies more precisely defined and classified these tumors, and assisted in determining a therapeutic protocol. The therapy for postirradiation sarcomas includes extirpative operation when possible, but the role of chemotherapy is uncertain. The aggressive behavior of these neoplasms was attested to by the death of three patients within 18 months of their operations.