2902 - Cervical Osteomyelitis with Head and Neck Cancer Radiotherapy: Single Institutional Experience

Purpose/Objective(s): Cervical osteomyelitis (OM) is a rare complication of head and neck cancer (HNC) treatment. OM has been linked to surgical intervention of the posterior pharyngeal wall; the impact of radiotherapy (RT) is unknown. One institutional experience is here presented.

Materials/Methods: A health system patient registry was screened for HNC patients receiving radiotherapy; direct record text search supplemented by in-house large language model (LLM) queries for cervical osteomyelitis, discitis, and spondylo(disc)itis defined the evaluable cohort, with subsequent manual chart review capturing patient demographics and oncologic characteristics.

Results: 3,635 unique HNC patients undergoing RT between 2013 and 2024 were identified. Text-based search yielded 47 potential cases, with multiple LLM evaluations identifying 21 cases for review. 11 patients were MR-confirmed; 2 with pre-HNC OM were excluded, as were 3 non-H&N related cases of OM following treatment (1 T-spine, 2 L-spine). All resultant 6 cases were squamous cell carcinoma (2 female; median age 59 [48-78]; 2 oropharynx, 2 oral cavity, 1 nasopharynx, and 1 larynx receiving total laryngectomy; 3 stage T3+N1+). Comorbidities included vascular disease (4), type 2 diabetes (2), poorly controlled HIV (1), and prior non-H&N malignancy (2). 5 patients received surgery prior to radiotherapy. 4 received adjuvant 60-66 Gy/30fx, 2 definitive 70 Gy/35fx (1 NPX, 1 recurrent oral cavity); 4 received concurrent chemotherapy. 4 patients experienced recurrence, including the definitive cases treated with subsequent re-resection in one (OC) and resection with a non-invasive stereotactic radiosurgery instrument and then 50 Gy / 5fx SBRT (NPX) in another. One patient experienced stenotic trachea with resection and reconstruction; another multiple reconstruction with tracheostomy. 2 had notable wound healing complications. 2 patients developed OM prior to RT. For post-RT OM cases, median time to symptoms was 267 days (19 days - 4.8 years, n=4) and 204 days (26 days – 5.11 years, n=6) post-surgery. OM occurred in skull base (1), C2-3 (1), C3-4 (1), C3-6, and C5-6 levels, with neck pain the most common presenting symptom. 2 patients experienced quadriplegia due to OM development. 4 patients in this cohort had died at time of writing, with 2 from osteomyelitis complications.

Conclusion: Cervical osteomyelitis is a rare but severe complication in HNC, with cases possible years after treatment. Overall rate in this series was 0.2%. Disease recurrence with repeat complex surgeries and comorbidities worsening wound healing suggest a multifactorial etiology. The contribution of radiotherapy is unclear but may increase OM likelihood in subsequent repeat interventions for toxicity or recurrence. Early recognition and aggressive management are crucial to improving outcomes.