Adjuvant stereotactic body radiotherapy±cetuximab following salvage surgery in previously irradiated head and neck cancer.

OBJECTIVES/HYPOTHESIS: Locoregional recurrence remains the primary failure pattern following salvage surgery for previously irradiated head and neck cancer; randomized trials have suggested a complimentary role for adjuvant chemotherapy and conventional reirradiation at the expense of significant increases in toxicity. We aimed to identify if stereotactic body radiotherapy (SBRT) ± cetuximab improves tumor control while reducing treatment-related toxicity following salvage surgery.

STUDY DESIGN: Retrospective review (2005-2011) of 28 patients with high-risk features (positive surgical margins or extranodal extension) following macroscopic complete (R0/R1) salvage surgery treated with adjuvant SBRT±cetuximab.

METHODS: SBRT consisted of 40 to 44 Gy in five fractions over 1 to 2 weeks with concurrent cetuximab (n=7) administered at 400 mg/m2 day -7+250 mg/m2 days 0 and +8. Toxicity was physician recorded, and University of Washington Quality of Life Revised surveys were prospectively collected.

RESULTS: All patients received prior radiotherapy (median, 70 Gy; range, 54-99 Gy) with a median reirradiation interval of 25 months (range, 6-156 months). At a median follow-up of 14 months (range, 2-69 months), the 1-year locoregional control, distant control, disease-free survival, and overall survival were 51%, 90%, 49%, and 64%, respectively. Rates of acute and late severe (≥grade 3) toxicity were low at 0% and 8%, respectively. At a median follow-up survey time of 6 months, 56% of patients reported improved/stable overall quality-of-life scores.

CONCLUSIONS: Adjuvant SBRT±cetuximab following salvage surgery is well tolerated with acceptable oncologic outcomes and little toxicity. Future prospective trials should evaluate adjuvant SBRT±cetuximab versus a wait-and-see approach for recurrent head and neck cancers with high-risk features following salvage surgery.

LEVEL OF EVIDENCE: 4.