Neoadjuvant immunochemotherapy and new radiomic predictor for resectable locally advanced oral squamous cell carcinoma.
Authors: Liu Lei , Li Yi , Li Chunjie , Xz Xiang , Zhang Zhuoyuan , Xie Huixu , Tang Yueyang , Zhang Bowen , Tan Chenfeng , Zhao Guile , Zeng Yuanyuan , Wang Jun , Xiong Wenju , He Mingmin 
Published: July 2024

6090 Background: The effectiveness of neoadjuvant immunochemotherapy (NAIC) in treating resectable locally advanced oral squamous cell carcinoma (LAOSCC) remains uncertain, with a notable lack of precise prognostic markers for NAIC outcomes. Methods: A single-arm prospective phase II trial was performed to assess the efficacy and safety of NAIC, consisting of 2 cycles of intravenous camrelizumab (200 mg), albumin paclitaxel (260 mg/m²), and cisplatin (75 mg/m²) administered every 3 weeks prior to radical surgery in LAOSCC patients. Adjuvant radiotherapy or chemoradiotherapy was determined by post-surgical pathology. Patients with previously untreated, stage III-IVB LAOSCC (the 8th edition of UICC/AJCC staging system), aged 18-75 years were enrolled. The primary endpoints were major pathological response (MPR, defined as ≤10% residual viable tumour (%RVT) cells) and safety, the second primary point was objective response rate (ORR) according to RECIST 1.1. To identify potential radiomic markers predictive of NAIC benefit, oscillating-gradient spin-echo (OGSE) magnetic resonance imaging sequences were obtained before and after NAIC. Results: From Feb 1, 2023 to Jan 1, 2024, 30 patients were enrolled, among which, 26 patients have received NAIC followed by surgery. The MPR rate was 65.4% (17/26), including a 34.6% (9/26) pathological complete response. Patients with PD-L1 (Combined Positive Score) ≥ 1 had higher MPR (80.0%, 16/20) than those with PD-L1 < 1 (16.7%, 1/6). NAIC was well-tolerated, without adverse effects on subsequent surgery, only two patients experienced grade 3 or 4 adverse events during NAIC, including one with grade 4 neutropenia (3.8%), and one with grade 3 thrombocytopenia (3.8%). The ORR was 80.8% (21/26), with 15.4% (4/26) complete response, 65.4% (17/26) partial response, and with no cases of progressive disease observed. The mean cell diameters of the whole tumor were calculated based on the OGSE sequences, twenty patients completed the OGSE scaning pre- and post-NAIC treatment. Pearson correlation analyses found that small post-NAIC mean cell diameter significantly related with fewer %RVT ( p = 0.026), supporting its potential as new radiomic predictors of NAIC efficacy. Among patients with MPR, the cell diameters were significantly decreased after NAIC, with a mean cell diameter of 18.87 ± 2.49 μm and 14.77 ± 1.85 μm for pre- and post-NAIC tumor, respectively ( p = 0.001). Conclusions: Camrelizumab combined with albumin paclitaxel/cisplatin as NAIC for LAOSCC demonstrates promising MPR and well safety. Mean cell diameter of tumor, derived from OGSE sequences, emerges as a potential new radiomic marker for predicting NAIC efficacy. Ongoing follow-ups on long-term survival and the development of a bio-radiomic prediction model integrating pathological features with OGSE data are underway. Clinical trial information: ChiCTR2200066119.