Abstract 415P
Background
Although immunotherapy has been the standard treatment for recurrent head and neck cancer, patients have limited benefit from this treatment. It is better to combine with radiotherapy, especially pulsed low dose rate radiotherapy (PLDR), since researches have confirmed that PLDR is the best way to treat recurrent tumors as well as to magnify immune response.
Methods
Clinical locoregional recurrent HNSCC patients were enrolled in the study. All the tumors were unresectable either for wrapping around the vessels or old ages. Patients received pulsed radiation therapy concurrent with 3 cycles of tislelizumab (200mg Q3W) followed by an additional 32 cycles of tislelizumab maintenance therapy. The primary endpoint was the objective response rate (ORR).
Results
Between Sep 2022 and Dec 2023, 12 patients (6 oral cavity, 3 hypopharynx and 3 larynx) were enrolled. The median age was 62 (53-80) years, 75.0% smoking history, 75.0% alcohol history and 83.3% male. The median long diameter of the primary lesion was 7.4 cm (2.6-12 cm). All patients completed radiotherapy with the CR rate was 58.3% (7/12), and the PR rate of 41.7% (5/12). At a median follow-up of 13.7 months, the median PFS or OS was not reached and 1-year PFS rate was 50.9 %. The most common adverse events were mucositis (100%) and G3-4 mucositis was found in 1 patient (8.3%). All patients with adverse events in this study were managed well.
Conclusions
The efficacy and safety of PLDR with tislelizumab is superior to standard of care (immunochemotherapy) and deserves further exploration.
Clinical trial identification
NCT05595590.
Editorial acknowledgement
Legal entity responsible for the study
Tianjin Medical University Cancer Institute & Hospital.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.