Improved local control and survival outcomes with RADPLAT in T4 oropharyngeal cancer: a retrospective study

Standard treatments for locally advanced oropharyngeal cancer (OPC) include surgery and chemoradiotherapy (CRT). While surgery offers good tumor control, it often results in significant postoperative functional impairments. Conversely, intravenous chemoradiotherapy (IV-CRT) is less effective in controlling primary tumors in T4 OPC cases and offers limited options for salvage surgery after recurrence. RADPLAT, a treatment involving intra-arterial cisplatin combined with radiotherapy, has demonstrated favorable results for other cancers and may offer an alternative treatment for OPC.

This retrospective study compared the efficacy and safety of RADPLAT and IV-CRT in the patients with T4 OPC treated at Hokkaido University Hospital between 2003 and 2022. The primary endpoint was local recurrence-free survival (LRFS), and the secondary endpoint was overall survival (OS).

Fifty-six patients were included, with 29 in the RADPLAT group and 27 in the IV-CRT group. The RADPLAT group showed significantly better LRFS (2-year LRFS: 82.3%) and OS (5-year OS: 73.8%) compared to the IV-CRT group (2y-LRFS: 66.0%, 5y-OS: 45.7%). Multivariate analysis identified RADPLAT as an independent favorable prognostic factor for both LRFS and OS. There was no significant difference in the incidence of adverse events between the two groups, although grade 3 or higher mucositis was more common in the RADPLAT group. Swallowing function and tracheostomy rates were similar between the groups.

RADPLAT provides superior local control and survival outcomes compared to IV-CRT for T4 OPC, with comparable safety and functional preservation. These findings suggest that RADPLAT may be a promising alternative to IV-CRT for cases with T4 OPC.