Is intra-arterial infusion chemoradiotherapy more effective than surgery in patients with locally advanced oral squamous cell carcinoma? A systematic review and meta-analysis for the update of the 2019 Japanese oral cancer clinical practice guidelines

This study evaluated the effectiveness of intra-arterial infusion chemoradiotherapy (IACRT) compared to surgery in patients with locally advanced oral squamous cell carcinoma (LAOSCC) as part of the process of updating the 2019 Japanese oral cancer clinical practice guidelines. We searched PubMed, Japana Centra Revuo Medicina Web, and the Cochrane Central Register of Controlled Trials (from 2019 to 2022) to identify articles that evaluated the effectiveness of IACRT and surgery in patients with LAOSCC. Because no randomized controlled trials were identified, we searched observational studies, such as cohort studies and case-control studies. A total of 337 articles were identified, and two studies were selected through the search. The only primary endpoint that was assessed was the locoregional recurrence rate. The hazard ratio for the locoregional recurrence rate was 1.03, with a 95% confidence interval of 0.77-2.18, and the point estimate was slightly in favor of the control group. However, there were large discrepancies between the proportions of early-stage OSCC and LAOSCC in the two articles. The balance between the desirable and undesirable effects of the intervention was not known. The certainty of evidence was very low. In this systematic review, the evidence of a desirable effect was small, and the balance between effectiveness and harms was not known. Some Japanese hospitals have reported good outcomes with IACRT for patients with LAOSCC. We must therefore exercise caution in analyzing this result.