Introduction

Tongue cancer is a significant health concern, particularly among adults. It represents a subset of head and neck cancers with high morbidity and mortality rates. Despite advances in treatment modalities, the prognosis for patients with advanced stage disease remains poor. Stage III tongue cancer poses unique challenges due to its aggressive nature and propensity for local invasion and metastasis. Traditional treatments such as surgery, radiation therapy, and chemotherapy have shown limited success in improving long-term survival. These limitations highlight the need for novel therapeutic strategies that can enhance outcomes for these patients.1–3

Immunotherapy has emerged as a promising approach in oncology. Immune checkpoint inhibitors target pathways that tumors exploit to evade immune detection and destruction. By blocking inhibitory signals, these agents can restore the ability of the immune system to recognize and attack cancer cells.4,5 Several studies have demonstrated the efficacy of immune checkpoint inhibitors in various malignancies including melanoma, lung cancer, and renal cell carcinoma.6,7 However, their role in head and neck cancers, specifically tongue cancer, remains underexplored. This gap in knowledge underscores the necessity of investigating the potential benefits of immune checkpoint inhibitors in this patient population.

Camrelizumab, a humanized anti-programmed cell death protein 1 (PD-1) monoclonal antibody, has been approved by the National Medical Products Administration (NMPA) in China for the treatment of multiple malignancies, including classic Hodgkin’s lymphoma, hepatocellular carcinoma, non-small cell lung cancer, and esophageal squamous cell carcinoma. Although not yet formally approved for head and neck squamous cell carcinoma (HNSCC), camrelizumab has been extensively investigated in this setting.8 Recent Phase II trials have demonstrated encouraging efficacy and acceptable safety profiles for camrelizumab-based regimens in both the neoadjuvant/perioperative setting for locally advanced HNSCC and as first-line treatment for recurrent or metastatic HNSCC.9,10 These findings provide a strong clinical rationale for exploring the potential benefit of camrelizumab as an adjuvant therapy in stage III tongue cancer, a specific and under-represented subgroup of HNSCC.

Functional recovery is a crucial aspect of patient care following treatment for tongue cancer. Surgical resection and adjuvant therapies often result in significant functional impairments, particularly in swallowing and speech. These deficits can severely impact quality of life and necessitate comprehensive rehabilitation efforts. Enhancing functional recovery through targeted therapies could not only improve physical well-being but also contribute to better psychological outcomes. Exploring the effects of immune checkpoint inhibitors on functional recovery may reveal additional benefits beyond tumor control. Improved functional outcomes could lead to enhanced patient satisfaction and overall quality of life.11,12

Overall, this study evaluates the impact of adjuvant targeted immune checkpoint inhibitor (TICI) therapy on both oncologic and functional outcomes in stage III tongue cancer. It explores ways to boost survival and recovery and improve quality of life. By focusing on these goals, this study may add to what we know about using immunotherapy in head and neck cancers. More research should look deeper into the reasons behind these findings and find markers that predict success. Such work will help develop better treatments and benefit patients with tongue cancer.

Materials and MethodsPopulation and Criteria

A retrospective analysis was conducted on 67 patients with stage III tongue cancer who underwent surgical treatment at our hospital from April 2017 to March 2020. Inclusion criteria were: (a) age between 18 and 70 years; (b) postoperative pathological confirmation of tongue squamous cell carcinoma (TSCC);13 (c) classified as stage III tongue cancer according to the American Joint Committee on Cancer (AJCC)14 Eighth Edition Cancer Staging System; (d) presence of high-risk factors for postoperative adjuvant therapy, including but not limited to positive surgical margins, extracapsular nodal spread, perineural invasion, vascular emboli, and poorly differentiated tumors; (e) Eastern Cooperative Oncology Group (ECOG)15 performance status score of 0–2; and (f) complete medical records without missing data. Exclusion criteria were: (a) severe dysfunction of vital organs such as heart, lung, liver, or kidney; (b) presence of cerebrovascular diseases, Parkinson’s disease, myasthenia gravis, or primary neurogenic dysphagia due to abnormal throat structure; (c) psychiatric disorders or cognitive impairment; and (d) previous anti-tumor treatment prior to surgery or history of malignancy in other sites.

The AJCC TNM staging system14 evaluates tongue cancer based on three dimensions: T stage (tumor size and local invasion), N stage (lymph node metastasis), and M stage (distant metastasis). Lower TNM stage numbers indicate a better disease status, with smaller tumors, no lymph node metastasis, and no distant spread, while higher numbers signify more severe disease conditions. For stage III tongue cancer specifically, the classification includes T1-2 tumors with N1 nodal disease, or T3 tumors with N0-N1 disease.

Grouping and Ethics

Based on the different postoperative adjuvant treatment protocols, the 67 patients were defined into the convention group (n=36) and the targeted immune checkpoint inhibitor (TICI) group (n=31). The convention group was defined as patients who received only standard adjuvant therapy after surgery, including postoperative radiotherapy (PORT) or concurrent chemoradiotherapy (CCRT) with cisplatin. PORT was delivered at a total dose of 60 Gy in 30 fractions over 6 weeks, administered five times per week. CCRT involved intravenous infusion of cisplatin (approved drug number H37021356, produced by Qilu Pharmaceutical Co., Ltd., Shandong Province) at 75 mg/m2 during the first and fourth weeks of PORT. The TICI group was defined as patients who, in addition to standard adjuvant therapy, received additional PD-1 inhibitor (camrelizumab) treatment. The regimen for camrelizumab involved intravenous infusion every 3 weeks (approved drug number S20190027, Suzhou Shengdia Biopharmaceutical Co., Ltd, China) at 200 mg, completing a total of 6 cycles. All patients were followed up starting from the day of completion of postoperative adjuvant therapy, with a duration of 5 years.

Treatment allocation was not randomized. Patients in the TICI group were selected based on multidisciplinary team (MDT) consensus, patient preference, absence of contraindications to immunotherapy, availability of camrelizumab after its introduction into our hospital formulary in mid-2019, and financial capacity. Patients in the convention group were those treated before camrelizumab became available or those who declined immunotherapy. All consecutive patients meeting the eligibility criteria during the study period were included.

This study protocol has been approved by the Institutional Review Board (IRB) of our institution with the decision of “approval to conduct retrospective research, waiving informed consent” (Approval Number: 2023DZKY-068-02). The waiver was based on the exemption criteria outlined in the “Ethical Review Measures for Biomedical Research Involving Human Subjects (2023 Edition)”, which states that the use of anonymized retrospective data, where the research findings do not directly relate to individual privacy and the risk is below minimal risk, qualifies for exemption. This study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki.

Observation OutcomesRecurrence-Free Survival (RFS)

RFS was defined as the time from the completion of postoperative adjuvant treatment to the first occurrence of tumor recurrence/metastasis or the end of follow-up.

Recovery of Swallowing Function

Swallowing function was assessed using the 10-item Eating Assessment Tool (EAT-10) before and 1 month, 3 months, 6 months, and 12 months after treatment. This scale consists of 10 items related to daily eating, with each question scored on a Likert scale from 0 to 4, where 0 indicates normal swallowing and 4 indicates severe impairment. The total score ranges from 0 to 40, with lower scores indicating better swallowing function, and a score of ≥3 suggests clinically significant dysphagia. The Cronbach’s α coefficient for this scale is 0.96.16

Recovery of Speech Function

Speech function was assessed using the Radboud Dysarthria Assessment (RDA) scale before and 1 month, 3 months, 6 months, and 12 months after treatment. This scale evaluates six dimensions: respiratory support, phonation, resonance, articulation, prosody, and speech intelligibility. Each dimension is scored on a Likert scale from 0 to 3, where 0 indicates normal function and 3 indicates severe impairment. The total score ranges from 0 to 18, with lower scores indicating better speech function. The Cronbach’s α coefficient for this scale is 0.90.17

Quality of Life

Quality of life was assessed using the University of Washington Quality of Life (UW-QOL) scale before and 1 month, 3 months, 6 months, and 12 months after treatment. This scale scores 12 items including appearance, swallowing, speech, eating, taste, pain, activity, social disability, psychological distress, saliva, recreation, and return to work. Each item is scored on a scale from 0 to 100 (0 = worst state, 100 = best state). The total score is calculated by summing the scores of the 12 items and then dividing by 12 (total score range 0–100), with higher scores indicating better overall quality of life. The Cronbach’s α coefficient for this scale is 0.85.18

Safety

Treatment-related adverse events (AEs) were documented throughout the follow-up period and graded according to the Common Terminology Criteria for Adverse Events (CTCAE- Version 5.0).19 Immune-related adverse events (irAEs) were specifically recorded for the TICI group, including skin reactions (rash, reactive cutaneous capillary endothelial proliferation [RCCEP]), endocrine disorders (thyroiditis, hypothyroidism), gastrointestinal symptoms, pneumonitis, hepatitis, and infusion-related reactions. Treatment delays (defined as > 7 days between scheduled cycles) and permanent discontinuations due to toxicity were also recorded.

Statistical Analysis

Statistical analysis was performed using SPSS software (version 29.0; developed by SPSS Inc., Chicago, IL, USA). Initially, normality tests were conducted, and it was confirmed that all continuous variables in this study followed a normal distribution, thus they were expressed as mean ± standard deviation (M±SD) and compared between groups using independent samples t-tests. For longitudinal functional outcomes (EAT-10, RDA, and UW-QOL), linear mixed-effects models (LMM) were employed with group, time, and group-by-time interaction as fixed effects and patient-specific random intercepts. This approach accounts for within-subject correlations and uses all available data under the missing-at-random assumption. Categorical variables were expressed as frequencies and percentages [n (%)] and compared between groups using the χ2-test. A p-value less than 0.05 was considered statistically significant. Subsequently, a multivariate Cox proportional hazards regression analysis was conducted on RFS to explore the independent risk factors affecting RFS. Additionally, a multivariate logistic regression analysis was performed on poor swallowing function recovery (EAT-10 ≥ 3 points) to identify the independent risk factors affecting poor functional recovery.

Given the exploratory nature of this study, no formal sample size calculation was performed a priori. A post hoc power analysis was subsequently conducted using G*Power 3.1 to evaluate the adequacy of the cohort. For RFS, the study achieved approximately 82% power to detect the observed hazard ratio (HR=0.689) at α=0.05. To minimize the risk of overfitting in the multivariate regression models, we limited the number of covariates to three (TICI use, T stage, and N stage) based on the number of events available (31 for RFS, 28 for swallowing recovery), ensuring an events-per-variable ratio exceeding the recommended threshold of 10 for Cox regression and approximately 9 for logistic regression. Multiple comparisons were performed across four postoperative time points for swallowing, speech, and quality-of-life assessments. To control the family-wise error rate, the Benjamini–Hochberg false discovery rate (FDR) procedure was applied within each outcome domain. All reported results remained statistically significant after FDR correction.

ResultsGeneral Data

Comparing the demographic characteristics between the Convention group and the TICI group (Table 1), no significant differences were found for age, gender, BMI, smoking history, drinking history, diabetes mellitus, hypertension, or ECOG scores (all P>0.05). These results indicated that the two groups were largely similar in demographic and clinical characteristics.

Table 1 Comparison of Demographic Characteristics Between Two Groups

In comparing the clinical features between the Convention group and the TICI group (Table 2), no significant differences were found for tumor size (P=0.761), T stage (χ2=0.433, P=0.805), N stage (χ2=0.104, P=0.747), total number of lymph node metastases (P=0.612), or any high-risk factors for postoperative adjuvant therapy (all P>0.05). The distribution of conventional adjuvant therapy types (PORT vs CCRT) was also similar (χ2=0.083, P=0.774).

Table 2 Comparison of Clinical Features Between Two Groups

RFS

Median follow-up duration was 36 months (interquartile range [IQR]: 29–42). During follow-up, 22 (61.11%) patients in the convention group and 9 (29.03%) patients in the TICI group developed recurrence or metastasis. The median RFS was not reached in the TICI group and was 30 (95% confidence interval [CI]: 24–35) months in the convention group (log-rank P<0.001, Figure 1). Patients without recurrence were censored at the date of last follow-up or at the end of the 5-year observation period. There was no significant difference in censoring rates between groups (P=0.412).

Figure 1 RFS Kaplan–Meier curve.

Abbreviations: RFS, Recurrence-Free Survival; TICI, Targeted Immune Checkpoint Inhibitor.

Recovery of Swallowing Function

In comparing EAT-10 scale scores between the Convention group and the TICI group (Figure 2), no significant difference was observed at baseline (15.36 ± 3.25 vs 15.42 ± 3.18, t=0.076, P=0.939). However, significant differences emerged over time. One month after treatment, the TICI group had a lower score than the Convention group (11.23 ± 2.76 vs 12.75 ± 2.94, t=2.171, P=0.034). This trend continued at three months (7.82 ± 2.15 vs 9.17 ± 2.31, t=2.463, P=0.016), six months (4.65 ± 1.52 vs 5.79 ± 1.67, t=2.903, P=0.005), and twelve months post-treatment (2.78 ± 0.92 vs 3.55 ± 1.04, t=3.171, P=0.002). Additionally, LNM analysis demonstrated significant main effects of treatment group (P=0.011) and time (P<0.001), as well as a significant group × time interaction (P=0.014), indicating that the improvement over time was greater in the TICI group.

Figure 2 Comparison of EAT-10 scale between two groups (scores). ns: no significant difference; *:P<0.05; **: P<0.01.

Abbreviations: EAT-10, 10-Item Eating Assessment Tool; TICI, Targeted Immune Checkpoint Inhibitor.

Recovery of Speech Function

In comparing the RDA scale scores between the Convention group and the TICI group (Table 3), there was no significant difference in RDA scale scores between the two groups at baseline (10.25 ± 2.36 vs 10.31 ± 2.41, t=0.093, P=0.926). One month after treatment, the TICI group showed a lower score compared to the Convention group (7.56 ± 1.98 vs 8.69 ± 2.15, t=2.216, P=0.030). This trend continued at three months (5.47 ± 1.58 vs 6.43 ± 1.72, t=2.369, P=0.021), six months (3.85 ± 1.23 vs 4.63 ± 1.35, t=2.455, P=0.017), and twelve months post-treatment (2.74 ± 0.81 vs 3.46 ± 0.99, t=3.249, P=0.002). Additionally, LNM analysis demonstrated significant main effects of treatment group (P=0.017) and time (P<0.001), as well as a significant group × time interaction (P=0.021), indicating that the improvement over time was greater in the TICI group.

Table 3 Comparison of RDA Scale Between Two Groups (Scores)

Quality of Life

Comparing the UW-QOL scale scores between the Convention group and the TICI group (Table 4), no significant difference was found at baseline (58.36 ± 8.45 vs 57.92 ± 8.63, t=0.211, P=0.834). One month after treatment, the TICI group had a higher score than the Convention group (66.47 ± 7.35 vs 62.65 ± 7.92, t=2.036, P=0.046). This trend continued at three months (73.25 ± 6.52 vs 69.43 ± 6.84, t=2.330, P=0.023), six months (79.38 ± 5.64 vs 75.72 ± 5.97, t=2.563, P=0.013), and twelve months post-treatment (83.76 ± 4.87 vs 79.85 ± 5.23, t=3.144, P=0.003). Additionally, LNM analysis demonstrated significant main effects of treatment group (P=0.008) and time (P<0.001), as well as a significant group × time interaction (P=0.010), indicating that the improvement over time was greater in the TICI group.

Table 4 Comparison of UW-QOL Scale Between Two Groups (Scores)

Safety

In the TICI group, treatment related AEs of any grade occurred in 30 of 31 patients (96.77%) (Table 5). The most common events were RCCEP (48.39%), fatigue (32.26%), rash (25.81%), and hypothyroidism (19.35%). Grade 3 or 4 AEs occurred in 5 of 31 patients (16.13%), including immune mediated hepatitis (n=2), pneumonitis (n=1), and severe rash (n=2). No grade 5 (fatal) treatment related AEs were observed. Permanent discontinuation of camrelizumab due to toxicity occurred in 2 patient (6.45%). Dose delays (>7 days between cycles) occurred in 4 patients (12.90%), primarily due to grade 2–3 skin toxicity or transaminase elevation; all these patients subsequently completed the planned 6 cycles after appropriate management. In the convention group, grade 3 or 4 AEs were observed in 10 of 36 patients (27.78%), predominantly myelosuppression (n=5) and severe oral mucositis (n=9). No treatment related deaths occurred in either group.

Table 5 Comparison of AEs Between Two Groups [n(%)]

Multivariate Regression Analysis

The multivariate Cox proportional hazards regression analysis (Table 6) revealed that TICI was a protective factor against RFS shortening (P=0.008, HR=0.689, 95% CI: 0.572–0.830). Conversely, higher T stage (T3) (P=0.003, HR=1.587, 95% CI: 1.321–1.907) and N stage (N1) (P=0.002, HR=1.796, 95% CI: 1.495–2.158) were significant risk factors for RFS shortening.

Table 6 Multivariate Cox Proportional Hazards Regression Analysis of Risk Factors Affecting RFS

The multivariate logistic regression analysis (Table 7) showed that TICI was a protective factor (P=0.004, OR=0.612, 95% CI: 0.485–0.772). Higher T stage (T3) (P=0.002, OR=1.698, 95% CI: 1.346–2.142) and N stage (N1) (P=0.002, OR=1.865, 95% CI: 1.479–2.351) were significant risk factors for poor swallowing function recovery.

Table 7 Multivariate Logistic Regression Analysis of Risk Factors Affecting Poor Swallowing Function Recovery

Discussion

The use of TICI as adjuvant therapy in stage III tongue cancer patients has shown promising outcomes in improving RFS and functional recovery. This study provides valuable insights into the potential benefits of incorporating TICI into postoperative treatment protocols, highlighting its impact on various aspects of patient care including RFS, swallowing function, speech function, and quality of life. We acknowledge that this study was not designed to investigate the underlying biological mechanisms. We did not perform immune cell profiling, cytokine measurements, tissue biomarker analysis, or functional imaging. Consequently, all mechanistic interpretations presented in this discussion are hypothesis-generating rather than conclusive. Future studies incorporating correlative biospecimen analyses are needed to validate these speculative links.

The observation that TICI-treated patients experienced longer RFS compared to those receiving conventional adjuvant therapy underscores the importance of immunotherapy in preventing disease recurrence. The underlying mechanism likely involves the modulation of immune checkpoints such as PD-1/PD-L1 pathways, which are known to inhibit T-cell activation and effector functions. By blocking these inhibitory signals, TICI can enhance the anti-tumor immune response, leading to more effective elimination of residual tumor cells following surgery. TICI may also influence the tumor microenvironment by promoting infiltration of cytotoxic T lymphocytes and reducing the presence of immunosuppressive cells such as regulatory T cells and myeloid-derived suppressor cells. These changes collectively contribute to a more robust immune surveillance.20,21 Furthermore, TICI may stimulate the production of cytokines like interferon-gamma (IFN-γ), which not only enhances the cytotoxic activity of immune cells but also upregulates MHC class I molecules on tumor cells, making them more recognizable by the immune system. Another important aspect is the role of TICI in inducing immunological memory, where activated T-cells persist in the body and provide long-term protection against tumor recurrence. This sustained immune response could be particularly beneficial in preventing metastatic spread and secondary tumors, contributing to prolonged RFS.22,23

Swallowing function recovery is another critical aspect of patient care, especially after surgical interventions for tongue cancer. Our findings indicate that patients treated with TICI exhibited better recovery of swallowing function over time compared to those receiving conventional therapy. This improvement could be attributed to several mechanisms. The enhanced immune response facilitated by TICI might reduce inflammation and promote faster wound healing, which is essential for restoring normal swallowing function. TICI may mitigate the adverse effects of radiation therapy, commonly used in conventional adjuvant treatments, which can cause fibrosis and scarring in the head and neck region. Reduced fibrosis would allow for better muscle coordination and movement, crucial for effective swallowing.24,25 The anti-inflammatory properties of TICI could alleviate mucositis, a common side effect of chemoradiotherapy, thereby supporting better functional recovery. Additionally, TICI may promote angiogenesis in damaged tissues, enhancing oxygen and nutrient supply, which is crucial for the regeneration of muscle fibers and nerves involved in swallowing.26,27

Similarly, speech function recovery was observed to be superior in the TICI group. Speech impairment following tongue cancer treatment is often due to tissue damage and subsequent fibrosis. The enhanced immune response induced by TICI could facilitate tissue repair and reduce fibrotic changes, allowing for better articulation and voice quality. TICI can promote the resolution of inflammation through the induction of regulatory T cells and the production of anti-inflammatory cytokines like IL-10 and TGF-β. These cytokines help to modulate the inflammatory response and prevent excessive fibrosis, which is a major contributor to speech impairment.28 Additionally, the reduction in systemic inflammation mediated by TICI might lessen the burden on the vocal cords and surrounding structures, further aiding in speech recovery. Another important mechanism is the promotion of neuroplasticity, where TICI may enhance the regrowth and reorganization of neural circuits involved in speech control. This neuroplasticity is supported by the increased availability of growth factors and neurotrophins, which are stimulated by the improved immune environment created by TICI therapy. These improvements highlight the potential of TICI not only in controlling tumor growth but also in mitigating the collateral damage caused by aggressive treatments.29,30

Quality of life is a paramount concern for cancer survivors, and our results suggest that TICI therapy positively impacts this domain. Improved RFS and functional recovery likely contribute to better psychological well-being and overall health status. Moreover, the reduced need for repeated hospitalizations and intensive follow-up treatments associated with lower recurrence rates can significantly enhance patients’ daily functioning and social interactions. The holistic approach of combining immunotherapy with traditional treatments thus offers a comprehensive strategy for improving both clinical outcomes and patient-reported outcomes.31,32

The safety profile of camrelizumab in our cohort was consistent with previously reported data, with RCCEP being the most frequently observed irAEs—a known class-effect of this specific PD-1 inhibitor.33 Importantly, the rate of grade 3–4 adverse events did not differ significantly with the TICI group than in the conventional chemoradiotherapy group, suggesting that the addition of immunotherapy did not exacerbate overall severe toxicity, although this comparison is limited by the non-randomized design. The low permanent discontinuation rate indicates acceptable tolerability of the TICI regimen in the adjuvant setting. Nevertheless, clinicians should remain vigilant for potentially serious irAEs such as pneumonitis and hepatitis, which required prompt intervention in a small subset of patients. These safety findings, together with the observed improvements in RFS and functional recovery, support the clinical feasibility of integrating camrelizumab into adjuvant protocols for stage III tongue cancer, pending confirmation in larger prospective trials.

Despite the promising findings, it is important to acknowledge the limitations of this study. First, as a non-randomized, retrospective study, selection bias cannot be excluded. The decision to administer TICI was influenced by temporal availability, clinician judgment, and socioeconomic factors such as insurance coverage, rather than by randomization. These factors may confound comparisons between groups, despite adjustment for baseline characteristics in multivariate analyses. Second, this study is limited by its modest sample size and retrospective design. Although post hoc power analysis suggested adequate power for the primary endpoint, the relatively small cohort may limit the generalizability of subgroup findings. Furthermore, despite applying FDR correction, the risk of Type I error inherent to multiple comparisons cannot be entirely excluded. These limitations underscore the need for larger, prospective, randomized trials to confirm our findings. Third, the absence of systematic biomarker analysis to predict differential responses to TICI versus conventional therapy is a significant limitation. Future prospective trials should incorporate pre-treatment and on-treatment biospecimen collection to identify and compare candidate biomarkers—such as PD-L1 combined positive score (CPS), tumor mutational burden (TMB), circulating tumor DNA (ctDNA), and immune cell subset dynamics—between the two groups. Such investigations would not only refine patient selection but also unravel the complex interplay between the tumor immune microenvironment and therapeutic efficacy, thereby moving the field towards truly personalized adjuvant strategies for stage III tongue cancer. Finally, this study highlights the potential of TICI as an adjuvant therapy for stage III tongue cancer patients, demonstrating its positive impact on RFS, functional recovery, and quality of life. While these findings are encouraging, they underscore the need for further validation through prospective studies and detailed mechanistic investigations. Future investigations should move beyond clinical endpoints to explore the biological determinants of functional recovery after TICI therapy. Correlative studies that assess dynamic changes in tumor-infiltrating lymphocytes, PD-L1 expression, circulating immune subsets, and inflammatory cytokines before, during, and after treatment could reveal whether enhanced immune activation directly promotes tissue repair, reduces radiation-induced fibrosis, or facilitates neuroplasticity. Such integrated clinic-biological approaches would not only validate our clinical observations but also guide the development of combination strategies that maximize both antitumor efficacy and functional preservation.

Conclusion

In summary, this exploratory retrospective cohort study suggests that adjuvant anti-PD-1 (camrelizumab) therapy may improve RFS in patients with stage III tongue cancer, particularly those with T3 or N1 disease, and is associated with more rapid recovery of swallowing and speech function and enhanced quality of life. The safety profile was manageable. Given the inherent limitations of the retrospective design—including potential selection bias and the lack of biomarker data—these findings should be interpreted as hypothesis-generating. Prospective, randomized controlled trials with standardized functional outcome assessment and biomarker correlatives are warranted to confirm the risk-benefit profile of adjuvant anti-PD-1 therapy in this understudied population.

Data Sharing Statement

The datasets used during the present study are available from the corresponding author upon reasonable request.

Ethics Approval and Consent to Participate

This study protocol has been approved by the Institutional Review Board (IRB) of Jinling Hospital, Affiliated Hospital of Medical School, Nanjing University with the decision of “approval to conduct retrospective research, waiving informed consent” (Approval Number: 2023DZKY-068-02). The waiver was based on the exemption criteria outlined in the “Ethical Review Measures for Biomedical Research Involving Human Subjects (2023 Edition)”, which states that the use of anonymized retrospective data, where the research findings do not directly relate to individual privacy and the risk is below minimal risk, qualifies for exemption.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Funding

This work was supported by grants from the Jiangsu Commission of Health Medical Research Project (No.MQ2025011).

Disclosure

The authors report no conflicts of interest in this work.

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