ESTRO 2024 - Abstract Book

S2101

Clinical - Sarcoma, skin cancer, melanoma

ESTRO 2024

Ten AYAs and all children received radiotherapy with curative intent, and two AYAs only received palliative radiation due to poor response to chemotherapy and progression of the disease. All AYAs and children who went for surgery, received only adjuvant radiotherapy. AYAs received external radiotherapy with a total dose of 41.4 – 59.4 Gy, in fractions of 1.8 – 2.0 Gy, and children a total dose of 41.4 – 55.8 Gy, in fractions of 1.8 Gy (Table 2). Acute toxicity was reported for seven AYA and eight children, including symptoms of fatigue, nausea and diarrhea. Furthermore, radiation-induced dermatitis was reported in three AYA and six children, and radiation mucotitis in five AYA and three children. In both the AYA and pediatric cohort, three patients presented with a local recurrence within five years after primary treatment. The 5-year survival rate in pediatric patients was 83%, and 0% in AYA patients.

Conclusion:

In this retrospective cohort study, we found that the clinical presentation of AYAs with RMS is less favorable, and that AYAs and children were generally treated according to the same pediatric clinical trial protocols. AYAs received similar radiation doses compared to children, and the reported acute toxicities in our study showed no apparent differences between AYAs and children. However, AYAs had a poorer prognosis and a considerably lower survival rate compared to children. Full investigation of the complete AYA RMS cohort (N=22), including more radiotherapy parameters, will further elucidate the role of radiotherapy in the effectiveness, in terms of local control, survival and (late) toxicity.