A retrospective analysis of tislelizumab and GP regimen neoadjuvant therapy followed by concurrent chemoradiotherapy plus nimotuzumab in patients with high-risk nasopharyngeal carcinoma.

Abstract

e18060 Background: Efficacy of nasopharyngeal carcinoma (NPC) with T4 or N3 remains unsatisfactory due to high-risk of distant metastasis or recurrence, indicating the need of more comprehensive treatment. We aim to analysis the efficacy and safety of tislelizumab and GP regimen in combination with neoadjuvant therapy and concurrent chemoradiotherapy (CCRT) plus nimotuzumab in patients with high-risk NPC. Methods: Our team conducted a retrospective analysis of 44 adult patients with high-risk locally advanced (T4 or N3; M0) nasopharyngeal carcinoma between March 2021 and January 2022, the median follow-up time was 599 days. The patients had received neoadjuvant chemotherapy (gemcitabine,1000 mg/m2, days 1 and 8, cisplatin,80 mg/m2, day 1), and tislelizumab (200mg) on day 1 every 3 weeks for 4 cycles followed by chemoradiotherapy including intensity modulated radiotherapy (IMRT), lobaplatin and nimotuzumab. Lobaplatin was intravenously administered at a dose of 30 mg/m2 on days 1 and 22. Nimotuzumab was intravenously administered at a dose of 200 mg on day 1 every week for 6 weeks. All patients underwent response assessments during neoadjuvant therapy, chemoradiotherapy and follow-up at regular intervals. Results: 44 patients were identified with the median age being 50y(24y-70y). At neoadjuvant treatment period, 44 patients completed 170 cycles of the combination of tislelizumab and GP regimen. During concurrent chemo-radiotherapy period, 42 (95.45%) of 44 patients completed 6 weeks of nimotuzumab treatment and 41 (93.18%) of 44 patients completed 2 cycles of lobaplatin treatment. Overall, 20 patients (45.5%) had a complete response, and 24 (54.5%) had a partial response after neoadjuvant therapy before the start of chemoradiotherapy. At 3 months and 6 months after radiotherapy, 90.9% (40 of 44) and 97.7% (43 of 44) of the patients had a complete response. 42 of the 44 patients were alive (95.5%). 3 events of recurrence(1) or death(2) were recorded. 19 (43.2%) of 44 patients had grade 3-4 treatment-related adverse events, and grade 3-4 immune-related adverse events(irAE) was recorded in 3 patients (6.8%) in the entire treatment. Grade 3-4 irAEs were rash(2) and hypothyroidism(1). Conclusions: Neoadjuvant therapy with tislelizumab and GP regimen followed by concurrent chemoradiotherapy plus nimotuzumab seems to have promising efficacy, lower toxic effects and better treatment compliance, which is a new treatment strategy for high-risk NPC.