[Results of radiotherapy in recurrences of soft tissue sarcomas]

Published data for radiotherapy in soft tissue sarcomas refer in most of the cases to the use of irradiation for primary tumors. Experiences of radiotherapy in local recurrences are limited. The own treatment results of a multimodal treatment approach in a large number of patients will be analyzed for local tumor control rates, survival rates, side effects and prognostic factors and will be compared to the literature.

At the University Hospital Hamburg-Eppendorf a total of 98 patients with local recurrences of soft tissue sarcomas were irradiated between 1980 and 1993. The median age of the patients was 55 years. There was a large variety of different histologies. Grading was evaluable in 95 cases: G1 24 patients, G2 21 patients and G3 50 patients. Localisation was dominated by the extremities with 64.3%. Recurrences were reclassified: 21 patients had rT1-tumors and 77 patients had rT2-tumors. Twelve cases showed lymph node metastases and 9 patients distant metastases. Generally treatment included surgery and postoperative irradiation. R-classification showed R0 in 25, R1 in 20 and R2 in 48 cases. Neutrontherapy was prefered in 57 cases and neutron- and photontherapy in 22 cases. Local tumor control rates and survival rates were calculated using the Kaplan-Meier method. Side effects were scored using the RTOG/EORTC scoring system. Univariate and multivariate analyses were applied to evaluate prognostic factors.

Local tumor control rates at 5 years were 56.4%, for G1 75.2%, G2 52.5%, G3 47.1%, rT1 66.0%, rT2 53.6%, R0 63.4%, R1 42.3% and R2 53.2%, N0 61.1% vs. N1 31.7%. Survival rates at 5 years were 45.2%, for G1 64.8%, G2 66.9%, G3 25.0%, rT1 60.0%, rT2 41.5%, R0 64.2%, R1 49.3% and R2 32.7%. Acute side effects were scored as grade 1 and grade 2. The rate of grade 3 and 4 late effects was about 6%. Lymph node status was a significant factor for local control. Grade, residual tumor status, type of irradiation and the applied neutron dose were significant factors for survival.

Nowadays no standard treatment exists for local recurrences of soft tissue sarcomas. Treatment should be interdisciplinary. Local recurrences should be avoided by the consequent use of surgery and radiotherapy. It is important that local recurrences should be detected early. Neutrontherapy may bring advantages for local control of recurrences with macroscopic tumor residuals.