Salvage skull base surgery after proton beam therapy for recurrent sinonasal malignancies: A retrospective study

BackgroundThis study aimed to examine treatment outcomes and postoperative complications associated with salvage skull base surgery following radical proton beam therapy (PBT).MethodsNine patients who underwent salvage skull base surgery following curative PBT as the initial treatment at our institution between September 2002 and May 2023 were retrospectively reviewed.ResultsThe cohort comprised four males and five females with a mean age of 48.1 years. The average proton dose administered during initial therapy was 68.5 Gy (relative biological effectiveness). Among the salvage surgeries, eight were anterior skull base surgeries, and one was an anterior middle skull base surgery. No local recurrences or perioperative deaths were observed. Postoperative complications occurred in three patients (33.3%), all experiencing surgical site infections, with one also having cerebrospinal fluid leakage.ConclusionThe study demonstrates that salvage skull base surgery after PBT effectively achieves local control and safety in patients with recurrent sinonasal malignancies.