Low dose radiotherapy (LDRT) has been used for non-malignant conditions including Dupuytren's disease (DD). The DEPART clinical trial randomized hands to either Observation (Obs) or LDRT to assess impact on disease progression (trial registration ACTRN12618000951257). Here we report toxicity and quality of life (QOL) for the first 36 months of follow-up.

Key eligibility criteria included a clinical diagnosis of DD, a patient reported history of disease progression over the last six months and written informed consent. Hands were randomized 1:1 to Obs or LDRT to a dose of 30Gy in 10 fractions. Patients were scheduled to be assessed at baseline, 6, 12, 24, 36, 48, 60, 84 and 108 months post treatment, with specific toxicities graded (CTCAE v4.03). For QOL, QuickDash, URAM and pain were recorded at baseline and subsequently scheduled for 6, 12, 36, 60, 84 and 108 months. HREC approval: 2018-02-134-PVR-1.

Between 2018-24, 404 hands (202 Obs, 202 LDRT) were randomized, with this analysis at the current median follow-up of 36 months (IQR 24-48). 162 patients experienced a toxicity (4 obs, 158 LDRT [most commonly dermatitis, reduced sweating and localized oedema]), with 96.6% grade 1 and no grade 3 events. Of the 14 grade 2 (moderate) toxicities recorded, only 1 (reduced sweating) persisted up to 24 months. For QOL lower scores translates to less symptoms. Median baseline scores were equivalent between arms, but improved over time for the LDRT arm. 36 month scores for Obs v LDRT were: QuickDASH (17.8 v 10.9 [p=0.013]), URAM (4.8 v 3.1 [p=0.056]) and Pain (2.1 v 1.0 [p=0.001]).

Multicentre randomized controlled trials assessing radiotherapy for non-malignant conditions are feasible, and critical to establish efficacy and risks. LDRT for DD is well-tolerated, with minimal ongoing toxicities. QOL is possibly improved by LDRT. Follow-up is ongoing to assess longer term toxicities, QOL and LDRT's impact on disease control.