Background：Neoadjuvant chemoimmunotherapy (NACI) shows promise in oral squamous cell carcinoma (OSCC), but reliable noninvasive biomarkers for predicting pathologic complete response (pCR) remain scarce. Radiomics integrating intratumoral and peritumoral heterogeneity across multi-sequence MRI may offer novel insights into treatment response evaluation.

Methods: The data of 212 patients with OSCC after NACI were retrospectively collected and analyzed. Among these patients, 56 (26.4%) achieved pCR after NACI. Intratumoral and peritumoral habitat imaging (HI) was achieved using the K-means clustering algorithm applied to T1-weighted imaging (T1WI), axial T2-weighted imaging with fat suppression (T2WI), and contrast-enhanced T1-weighted imaging with fat suppression (T1C). Moreover, intratumoral and peritumoral HI models were constructed and compared using the receiver operating characteristic (ROC) curve. Five-fold cross-validation was performed to mitigate model overfitting.

Inclusion Criteria:

• Histopathologically confirmed OSCC at the initial diagnosis;
• No treatment received prior to the first MRI examination;
• Receipt of NACI;
• Underwent MRI examination after NACI;
• Underwent surgical intervention.

Exclusion Criteria:

• Absence of clinical data and postoperative pathological results;
• MRI image artifacts significantly affecting image quality.

This study comprehensively reviewed the clinical information of OSCC patients who underwent NACI at two institutions from March 2020 to December 2023.