Is there a role for reirradiation for SCC oral tongue with high-risk features (i.e., PNI, close margins) following surgery?

Consider in patients with ENE, positive margins, deeply infiltrative tumors (>1 cm), or T4. Avoid if <6 mo from prior RT, ongoing wound healing issues in target, or pre-existing severe toxicity (e.g., ORN, severe fibrosis), though this is conditional.

While re-irradiation of gross unresectable recurrent cancer has obvious DFS and survival benefits, the therapeutic ratio of adjuvant re-irradiation is less clear. Data about the interval since the previous RT, and the size of the re-RT PTV, may help. In our experience, where 38% of patients were treated postoperatively, both factors significantly affected the risks of severe toxicity, when treated as continuous predictors and when dichotomized: Patients who had intervals > 20 months between the radiation courses and PTV < 100 ccs, had 95% probability of being alive and free of severe toxicity at 2 years (Lee et al., PMID 27531870). While the interval between the radiation courses cannot be controlled, the CTV may be minimized postoperativel...