Identification and management of recurrent oral squamous cell carcinoma in the clinical presentation of osteoradionecrosis: a single-center case series for treatment experience sharing.

[INTRODUCTION] Radiotherapy is an integral component of the comprehensive and sequential treatment approach for advanced oral squamous cell carcinoma (OSCC). One of the significant complications associated with radiotherapy is osteoradionecrosis (ORN), which most frequently affects the mandible. Differentiating between osteoradionecrosis (ORN) and recurrent oral squamous cell carcinoma (ORSCC) can be challenging when relying solely on clinical and radiologic characteristics. The diagnosis becomes even more difficult when bone necrosis of jaw presents as the first clinical symptom.

[OBJECTIVES] This study aims to present the clinical manifestations and treatment processes of patients at our institution who have developed bone necrosis of jaw after radiotherapy and subsequently diagnosed with recurrent oral squamous cell carcinoma (ORSCC).

[CASE PRESENTATION] We have collected six patients with recurrent oral squamous cell carcinoma (ORSCC) who developed bone necrosis of jaw after radiotherapy. These patients subsequently underwent surgical repair and reconstruction and were eventually diagnosed with ORSCC. We present a case series reviewing their basic characteristics, radiological reports, surgical treatment, and pathological diagnosis. All six patients initially presented with oral or facial pain and were diagnosed with osteoradionecrosis (ORN) through imaging studies. All patients underwent surgical treatment, with free flaps used to repair postoperative defects. Among them, five patients were diagnosed with tumor recurrence through preoperative or intraoperative frozen biopsy, and one patient was confirmed with recurrence in the osseous resection through postoperative examination.

[CONCLUSION] Identified ORSCC in the suspected ORN of the jaw following radiotherapy is relatively rare, yet it poses identification challenges and can significantly impact treatment decisions. Consequently, surgeons must remain vigilant and ensure clear pathological diagnoses for suspicious patients, either before or during surgery.