In a patient treated with chemoradiation therapy for anal cancer 10+ years ago who presents again with localized anal squamous cell carcinoma, would you consider repeat chemoradiation for organ preservation instead of APR since so much time has passed since the first treatment?

No.

Usually no, and APR would be the most appropriate treatment option once all factors are considered. However, for small localized tumors, brachytherapy for local control may be considered but discussion regarding sphincter control is paramount as it may be compromised post reirradiation.

Usually no, but dependent on whether the new lesion is anal canal vs anal margin, size of lesion, and prior dose/fractionation of irradiation for the prior cancer. For a small superficial lesion, local excision may actually be a surgical option as shown in a small group of patients in a Mayo Clinic ...