Post-irradiation soft tissue sarcoma.

From 1975 to 1993, 11 of 375 patients treated for soft tissue sarcoma presented with post-irradiation sarcoma. The mean time interval between irradiation therapy and onset of the second neoplasm was 15.8 years (4-31 years). The total radiation dosage ranged from 12 to 60 Gy with a mean of 40 Gy. All patients had complete staging including CT or MRI of the tumour site, and CT of the lung. Surgical resection was the treatment of choice. Wide margins could be achieved in 10 patients. One had a marginal resection. Tumours included malignant fibrous histiocytoma, haemangiosarcoma, rhabdomyosarcoma, malignant schwannoma, fibrosarcoma and undifferentiated sarcoma. All patients were reassessed in our outpatient clinic. After a mean follow-up of 4.7 years (1.0-11.5 years), only 1 patient had died because of the tumour. Although post-irradiation sarcomas are rather infrequently observed, these tumours must be suspected when alterations or symptoms occur in a previously irradiated region. Early detection provides the chance of curative, wide margin resection.