2739 - Salvage Surgery Followed by IORT for Locoregionally Persistent or Recurrent Head and Neck Cancer
Presenter(s)
A. N. Elguindy1,2, K. N. Dibs1, N. Peters1, A. Koempel1, S. Zhu3, E. Gogineni1, S. J. Ma1, D. J. Konieczkowski1, M. Bonomi4, P. Bhateja4, K. VanKoevering5, N. Seim5, B. Klamer6, S. Kang5, C. T. Haring5, D. L. Mitchell1, M. Old5, A. Agrawal5, E. Ozer5, R. Carrau5, J. W. Rocco5, J. C. Grecula1, S. Baliga1, and D. M. Blakaj1; 1Department of Radiation Oncology, James Cancer Hospital/Wexner Medical Center, The Ohio State University, Columbus, OH, 2Department of Radiation Oncology, El-Demerdash Hospitals, Ain Shams university, Cairo, Egypt, 3Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, OH, 4Department of Medical Oncology, The Ohio State University Wexner Medical Center, Columbus, OH, 5The Ohio State University Department of Otolaryngology - Head & Neck Surgery, Columbus, OH, 6The Ohio State University Wexner Medical Center, Center for Biostatistics, Columbus, OH
Purpose/Objective(s): Patients with persistent or recurrent head and neck squamous cell carcinoma (rHNSCC) typically have poor survival outcomes. Salvage surgery with adjuvant external beam radiotherapy (EBRT) +/- chemotherapy remains the primary treatment approach but is associated with high rates of surgical morbidity and radiation toxicity. Intraoperative radiation therapy (IORT) delivers precise radiation doses to the tumor bed and minimizes exposure of radiation to normal tissues
Materials/Methods: In a retrospective single institution study, we aimed to assess the efficacy and safety of IORT after salvage surgery in rHNSCC. We captured all patients with rHNSCC who underwent salvage surgery and electron IORT from May 2001 to June 2024 at our NCI-Designated Cancer Center. All patients previously received EBRT as a component of their definitive or adjuvant therapy. Clinical outcomes were retrospectively reviewed, and univariate analysis was performed using log-rank test to correlate clinical outcomes with clinic-pathologic characteristics. Toxicity was reported based on CTCAE V5. Kaplan-Meier survival analysis was used to assess progression free survival (PFS), overall survival (OS), and local control (LC).
Results: We had 130 patients with a median follow up 15 months (IQR, 7.1-32.6) after IORT. The median IORT dose was 12.5 Gy (range, 7.5-17.5). Thirty percent had additional post-salvage radiation with median 44 Gy (IQR, 40-49.5), and 11% had concurrent chemoradiation. Regarding margin assessment, 60 patients (49%, n=60/123) had positive margins, and 14 (24%, 14/59) had extranodal extension (ENE) after neck dissection for regional recurrence. The median OS, PFS, and LC were 18.8, 8.7, and 18.2 months, respectively. The 1-year OS, PFS, and LRC were 63%, 40% and 59%, respectively. The 2-year OS was 42%. Patients with ENE had inferior 1-year OS compared to those without ENE (43% vs 69%, p= 0.02). The 1-year PFS was also significantly lower for patients with ENE (22% vs 55%, p=0.02), positive margins (30% vs 50%, p= 0.005), and LVSI (HR=2.09, 95%CI: 1.2-3.5, p=0.02). The rate of acute CTCAE V5.0 Grade = G3 toxicity was 7.6%. One patient (0.7%) had Grade 5 toxicity.
Conclusion: The combined salvage surgery with IORT is associated with acceptable local control and toxicity, which compares favorably to Janot et al. (2008). Importantly, treatment related death was low in our series (0.7%) compared to Janot (4%, n=5/130). Survival and progression were worse with positive ENE, positive margins, and LVSI, respectively.