The IMRiS Trial: A Phase II Study of Intensity-Modulated Radiotherapy in Extremity Soft Tissue Sarcoma.

PURPOSE: Primary soft tissue sarcoma (STS) is rare, with many tumours occurring in extremities. Local management is limb-sparing surgery and pre-operative/post-operative radiotherapy (RT) for patients at high risk of local recurrence. We prospectively investigated late normal tissue toxicity and limb function observed after intensity modulated RT (IMRT) in extremity STS. METHODS AND MATERIALS: Patients with extremity STS, age ≥16 years. Two treatment cohorts: IMRT 50Gy in 25 × 2Gy fractions (pre-operative) or 60/66Gy in 30/33 × 2Gy fractions (post-operative). Primary endpoint was rate of ≥ grade 2 late subcutaneous fibrosis at 24 months after IMRT (RTOG late radiation morbidity scoring). RESULTS: One hundred and sixty-eight patients were registered between March 2016-July 2017. Of those, 159 (95%) received IMRT (106, 67% pre-operative RT and 53, 33% post-operative RT) with a median follow-up of 35.2 months (IQR: 32.9 to 36.6); 62% male; median age 58 years. Of 111 patients assessable for primary endpoint at 24 months, 12 (10.8%, 95%CI: 5.7%-18.1%) had ≥ grade 2 subcutaneous fibrosis. The overall rate at 24 months of RTOG late skin, bone and joint toxicity was 7/112 (6.3%), 3/112 (2.7%) and 10/113 (8.8%), respectively, and for Stern's scale oedema was 6/113 (5.3%). More wound complications were observed with pre-operative than post-operative RT (29.2% vs 3.8%). Overall survival at 24 months was 84.6%, and local recurrence event rate at 24 months was 10%. CONCLUSIONS: The rate of ≥ grade 2 subcutaneous fibrosis at 24 months after IMRT was 10.8%, consistent with other recent trials of IMRT, and lower than historical reported rates in patients treated with 3D-CRT. This trial provides further evidence for the benefits of IMRT in this patient population.

Current approaches to management of bone sarcoma in adolescent and young adult patients.

Bone tumors are a group of histologically diverse diseases that occur across all ages. Two of the commonest, osteosarcoma (OS) and Ewing sarcoma (ES), are regarded as characteristic adolescent and young adult (AYA) cancers with an incidence peak in AYAs. They are curable for some but associated with unacceptably high rates of treatment failure and morbidity. The introduction of effective new therapeutics for bone sarcomas is slow, and to date, complex biology has been insufficiently characterized to allow more rapid therapeutic exploitation. This review focuses on current standards of care, recent advances that have or may soon change that standard of care and challenges to the expert clinical research community that we suggest must be met.