What dose and fractionation would you recommend for palliative-intent radiation therapy for cutaneous angiosarcoma in a patient with distant metastases?

For a patient with a fairly short time horizon, 30/10 is totally defensible and appropriate.

Small series have reported on a variety of other palliative regimens, for example:

39 Gy/13 fx

QuadShot

I think one could also consider 5 Gy x 5 or 6 Gy x 5, as we know both of those are safe even in the preop setting in STS.

For a patient with a longer time horizon, it may be worth being more aggressive. The only actual dose-response data for unresected STS that I know of shows a dose-response threshold ...