Randomized, controlled phase II study of post-surgery radiotherapy combined with recombinant adenoviral human p53 gene therapy in treatment of oral cancer

The aim of this study is to evaluate clinical benefits of recombinant adenoviral human p53 (rAd-p53) gene therapy combined with radiotherapy in prevention of oral cancer recurrence after a radical resection. A total of 51 patients with tongue cancer (TCa) and 56 patients with gingival carcinoma (GCa) satisfying the inclusion criteria were randomly assigned to two groups: the experiment group (EG) and the control group (CG). The EG group received multipoint injections of rAd-p53 into the surgical wound surface at a dose of 1 × 10¹² viral particles after a radical resection. Patients in both EG and CG were given radiotherapy at a total dose of 60 Gy at 3 weeks after surgery. All these patients were followed up for at least 3 years. Two cases (2/27) of TCa and 2 (2/30) in GCa patients had a local recurrence in EG, but 8 (8/24) TCa and 8 (8/26) GCa patients in CG had a local recurrence. Both recurrent rates of TCa (33.3%) and GCa (30.8%) in CG are statistically significantly higher than those of TCa (7.4%) and GCa (6.7%) in EG, respectively. The overall recurrent rate in EG is 7%, which is also statistically significantly lower than that (32%) in CG. The 3-year overall survival (OS) rate and 3-year disease-free survival (DFS) rate of EG is 100% and 93%, respectively. The 3-year OS and DFS rates of CG are 94 and 68%, respectively. Mild or medium fever and flu-like symptoms were more frequently observed in EG and were considered to be associated with application of rAd-p53. Post-tumorectomy wound surface injection of rAd-p53 combining with radiotherapy is a safe and effective regimen for the patients with TGa or GCa.