How would you manage a patient with recurrent, high-grade leiomyosarcoma involving the pelvis after salvage exenteration, but who has a focally positive anterior margin?

She had pelvic radiation 2 years ago. She initially had a 12 cm tumor resected to R1, and was treated with docetaxel/gemcitabine followed by adjuvant pelvic radiation 50.4 Gy/28fx. A multifocal pelvic recurrence occurred one year later, invading the pelvic floor and mesorectal fascia, with genomic testing revealing NF1, PTEN, and TP53 mutations. She had doxorubicin/trabectedin chemotherapy followed by a salvage pelvic exenteration. Post-operative pathology confirmed persistent disease invading the pelvic soft tissues, rectal layers, and vaginal submucosa, with a positive (focally involved) anterior surgical margin.