What dose and fractionation would you recommend for anal melanoma that is localized but refusing surgery?

I have treated patients with 30 Gy / 5 fractions with 2 fractions per week. There is some proctitis, for sure; and this is adapted from the adjuvant experience from MDACC. Patients have tolerated it well. We will then start immunotherapy after the radiation.

On the other hand, if the patient has a B...

I've also treated a patient with metastatic melanoma involving the low rectum, which may have been mucosal subtype, using SBRT 30 Gy in 5 fractions of 6 Gy each, every-other day. Immunotherapy was given concurrently and the patient had a rapid local response and stoppage of her bleeding. This fracti...