Do you treat early-stage dupuytrens disease with radiotherapy?

Yes. Below are excellent references with long-term results and descriptions of technique.

1. Betz, N., Ott, O.J., Adamietz, B. et al. Radiotherapy in Early-Stage Dupuytren's Contracture: Long-term results after 13 years. Strahlenther Onkol (2010) 186: 82-90.

2. Seegenschmiedt M.H., Keilholz L., Wielp¼tz M., Schubert C., Fehlauer F. (2012) Long-Term Outcome of Radiotherapy for Early Stage Dupuytren's Disease: A Phase III Clinical Study. In: Eaton C., Seegenschmiedt M., Bayat A., Gabbiani G., Werk...

Yes, and continue to look for updates from Europe where this is more common and under study. We published results and "How to suggestions" in 2017

Meredith R, Carlisle J, Dover L, López-Araujo J, Benhabib S, Brezovich I. Dosimetric comparison of radiation methods for palmar fiborsis. J ClinRadiat Oncol 2017; 2(1):1-3;

doi:10.14312/2397-8511.2017-1