[This corrects the article DOI: 10.3389/fimmu.2025.1576042.].

BACKGROUND:The optimal reconstructive approach following neoadjuvant immunochemotherapy (NICT) and surgery for locally advanced oral squamous cell carcinoma (OSCC) remains debated. This study compared pedicled submental island flap (SIF) and free flap (FF) reconstruction in this contemporary treatment setting. METHODS:We conducted a retrospective comparative study of 212 consecutive patients with locally advanced OSCC treated with NICT followed by surgery. Propensity score matching (1:1) yielded a balanced cohort of 54 SIF and 54 FF patients. Outcomes included disease-free survival (DFS), overall survival (OS), operative time, complications, recovery milestones, and patient-reported quality of life (QoL) assessed via EORTC QLQ-C30/H&N35 at baseline, 3, 6, and 12 months. RESULTS:Operative time and hospital stay were significantly shorter for SIF (4.5 ± 1.1 vs. 6.3 ± 1.4 h, p < 0.001; 8.1 ± 2.5 vs. 11.8 ± 3.1 days, p < 0.001). Flap survival and major complication rates were comparable (p > 0.05). Median follow-up was 38.5 months. No significant differences were observed in DFS (HR = 0.90, 95% CI: 0.41-1.98, p = 0.796) or OS (HR = 0.83, 95% CI: 0.34-2.00, p = 0.678). However, QoL recovery was superior in the SIF group, with significantly greater improvements in Global QoL (81.5 ± 8.2 vs. 73.9 ± 10.1, p < 0.001), physical and social functioning, and head and neck-specific symptoms (swallowing, speech) at 12 months. Linear mixed models confirmed a favorable SIF trajectory over time (time-by-group interaction p < 0.001). CONCLUSION:In patients with locally advanced OSCC undergoing NICT, SIF reconstruction offers comparable oncologic safety to FF while facilitating faster surgical recovery and yielding superior long-term functional and quality of life outcomes.

Achaete-scute homolog 2 (ASCL2), as a transcription factor, is overexpressed in various tumors and considered to be associated with malignant progression and poor prognosis of tumors. However, whether ASCL2 affects head and neck squamous cell carcinoma (HNSCC) progression has not been studied. We reported that ASCL2 was up-regulated in HNSCC tumor tissues compared to normal tissues, and that this increase was associated with adverse clinical outcomes. Cell-based characteristics revealed the pro-oncogenic effect of ASCL2 overexpression in cell proliferation, colony formation, sphere growth and migration/invasion through facilitating epithelial-mesenchymal transition (EMT). Knocking down ASCL2 resulted in growth arrest of HNSCC cells and the inhibition of malignant behaviors. The xenograft tumor model of ASCL2-expressing cells was larger, more prone to lymph node metastasis (LNM), and exhibited more significant characteristics of cancer stem cells (CSCs) (upregulated CD44, OCT4, and NANOG and increased stem cell frequency). Analysis between mRNA-seq and ChIP-seq showed that ASCL2 regulated the function of SNF2 histone-linker PHD-finger RING-finger helicase (SHPRH). SHPRH was inhibited in ASCL2-expressed HNSCC cells. Mechanistically, ASCL2 suppressed the transcriptional activity of SHPRH, subsequently leading to a weakened ability of SHPRH in inhibiting the proliferation, migration, invasion. Overexpressing SHPRH in ASCL2-expressed HNSCC cells alleviated the malignant behavior of tumor cells. In conclusion, our research revealed that ASCL2 promoted the proliferation, EMT and CSC characteristics of HNSCC cells by transcriptionally inhibiting the expression of SHPRH. Targeting this process might be a promising approach for HNSCC therapy.

The 8th edition AJCC TNM (TNM-8) staging framework frequently lacks distinct prognostic discrimination for minor salivary gland carcinomas (mSGCs). This multicenter study was designed to validate the proposed 9th edition (TNM-9) classification, which is tailored to better reflect the biology of these tumors, specifically in oral mSGCs. We conducted a retrospective cohort study encompassing 163 patients with primary oral mSGCs treated with curative intent across four tertiary cancer centers. All cases were re-staged using both TNM-8 and the proposed TNM-9 criteria. The primary endpoint was disease-specific survival (DSS). System performance was compared using the Harrell C-index, Akaike Information Criterion (AIC), categorical Net Reclassification Improvement (NRI), and Decision Curve Analysis. Under the TNM-9 system, survival curves for DSS showed clear and statistically significant separation across all stage groups (p < 0.001). In contrast, TNM-8 failed to significantly differentiate between Stage III and Stage IV outcomes. Advanced TNM-9 stages (IIIA and IIIB) were strong independent predictors of worse DSS. TNM-9 demonstrated superior discriminative ability compared to TNM-8 (C-index: 0.74 vs. 0.68) and a better model fit (AIC: 460 vs. 485). Additionally, TNM-9 correctly reclassified 23

Recurrent high-grade salivary gland carcinomas (SGCs) have limited treatment options, and immunotherapy’s role remains unclear. This study evaluated radiologic and pathologic responses to immunotherapy in resectable recurrent high-grade SGCs. We retrospectively analyzed 108 patients from a tertiary center: 41 received neoadjuvant immunotherapy, while 67 underwent upfront surgery. Radiologic response (RECIST 1.1) and pathologic response (immune-related criteria) were discordant—34.1% showed partial radiologic responses, but only 9.8% achieved partial pathologic responses, with no complete responses. PD-L1 amplification correlated with response (25% vs. 8.1% in non-responders, p=0.042), whereas B2M loss (29.3% post-treatment, p=0.032) and TP53/PIK3CA co-mutations (37.8% in non-responders) were linked to resistance. Survival did not differ between groups (3-year event-free survival: 19.5% vs. 23.9%, p=0.447; overall survival: 26.8% vs. 31.3%, p=0.593). These findings highlight immunotherapy’s limited pathologic efficacy in recurrent high-grade SGCs, with response rates lower on pathologic than radiologic assessment. PD-L1 and B2M alterations underscore the need for biomarker-driven strategies. This study provides a foundation for improving outcomes in this aggressive disease.

This study aimed to investigate the impact of varying distant metastatic burdens on prognosis in oral squamous cell carcinoma (OSCC) and to propose a novel staging system for distant metastasis. We retrospectively enrolled patients with primary stage IVc OSCC at diagnosis or those who developed confirmed distant metastasis within six months after curative treatment. These patients were divided into training and validation cohorts. The prognostic accuracy of the 8th edition AJCC staging system and our proposed staging system was evaluated based on overall survival (OS). Among the 586 patients analyzed, 317 were assigned to the training cohort. OS was significantly influenced by the number of metastatic foci and the number of affected anatomic sites, but not by the size of the metastatic foci. Compared to stage IVc1 (defined as ≤ 3 metastatic foci within a single anatomic site), stage IVc2 (4–5 metastatic foci in one site or 2–5 foci across two sites) and stage IVc3 (all other distant metastasis patterns) were associated with hazard ratios of 1.35 (95

BackgroundWhile circulating tumor DNA (ctDNA) assessment after surgery has emerged as a promising biomarker for minimal residual disease detection in solid tumors, its clinical utility for guiding the selection between postoperative radiotherapy (PORT) and chemoradiotherapy (POCRT) in head and neck squamous cell carcinoma (HNSCC) remains poorly characterized. We evaluated whether ctDNA-directed stratification could optimize locoregional control in HNSCC patients following neoadjuvant chemoimmunotherapy.MethodsIn this comparative cohort study, consecutive HNSCC patients treated with neoadjuvant chemoimmunotherapy were stratified into two management groups: a ctDNA-guided cohort where tumor-informed ctDNA testing determined POCRT administration given only for detectable ctDNA, and a traditional cohort where all patients received PORT, with postoperative chemotherapy decisions made by multidisciplinary team review based on pathologic response status and pretreatment imaging findings. The primary endpoint was 3-year locoregional control, with secondary analysis of POCRT utilization rates.ResultsAmong 257 patients who completed neoadjuvant chemoimmunotherapy, 209 (81.3%) underwent surgery with 187 (72.8% of treated patients) achieving major pathological response and comprising our study population. Of these, 69 (36.9%) received ctDNA-guided management, while 118 (63.1%) followed traditional protocols. POCRT utilization was significantly lower in the ctDNA-guided group (27.5% [19/69] vs 42.4% [50/118]; absolute difference -14.9%, p=0.042). ctDNA positivity rates were comparable between groups (ctDNA-guided: 27.5% [19/69] vs traditional: 29.6% [35/118], p=0.867). ctDNA-guided management demonstrated superior outcomes, with a 15% reduction in locoregional recurrence risk (adjusted HR 0.85, 95%CI 0.70-0.94; p=0.013) versus traditional management. Among ctDNA-positive patients, POCRT benefit was significantly greater in the ctDNA-guided cohort (HR 0.73, 95%CI 0.57-0.83; p=0.026) compared to ctDNA-positive patients receiving traditional management (HR 0.87, 95%CI 0.73-0.93; p=0.047; interaction p=0.039).ConclusionPostoperative ctDNA analysis identifies HNSCC patients who benefit most from POCRT, enabling a 41% relative reduction in treatment utilization while maintaining superior locoregional control. The enhanced therapeutic effect observed in ctDNA-guided patients supports ctDNA’s role as a decision-modifying biomarker for personalization management following neoadjuvant chemoimmunotherapy.

BackgroundTo assess the oncologic outcomes in patients with oral squamous cell carcinoma (SCC) who underwent treatment with radiotherapy (RT) or chemoradiation therapy (CRT) following neoadjuvant immunochemotherapy and surgery.MethodsData from patients who underwent neoadjuvant immunochemotherapy, surgery, and adjuvant therapy were collected prospectively and analyzed retrospectively. The primary outcomes assessed were 3-year overall survival and locoregional control. Secondary endpoints included the objective response rate (ORR), rates of pathologic complete response (pCR) and major pathologic response (MPR), as well as safety.ResultsA total of 137 patients were included in the analysis. Neoadjuvant therapy yielded an ORR of 81.7%, with pCR and MPR achieved in 47 and 73 patients, respectively. Grade III and IV adverse events were rare, comprising only 1.6% of all events. The addition of adjuvant chemotherapy to RT did not show a significant reduction in the risk of locoregional recurrence. However, with regards to overall survival, the hazard ratios were 0.85 (95% CI: 0.73-0.96) for the MPR group and 0.66 (95% CI: 0.37-0.89) for the pCR group, both significantly higher than that in patients with incomplete pathologic response. The addition of adjuvant chemotherapy to RT was associated with a 5% reduction in the risk of mortality (95% CI: 1%-14%), the protective effect of CRT was the most obvious in patients with MPR.ConclusionNeoadjuvant immunochemotherapy demonstrated high safety and efficacy in oral SCC. CRT was superior to RT in terms of overall survival especially in patients with MPR when administered following neoadjuvant immunochemotherapy and surgery.

Our objective was to examine the impact of elective neck dissection (END) on the prognosis of patients with cT2N0 maxillary sinus squamous cell carcinoma (MS-SCC) and to determine factors that predict the occurrence of occult metastasis in this patient population. A retrospective analysis was conducted using data from the SEER database. Patients with cT2N0 MS-SCC were included in the study and divided into two groups: those who received END and those who did not. The impact of END on disease-specific survival (DSS) and overall survival (OS) was assessed using propensity score matching. Multivariate logistic regression analysis was performed to determine predictors for occult metastasis. A total of 180 patients were included in the study, with 40 cases receiving END. Following propensity score matching, patients treated with END and those without showed similar DSS and OS rates. Occult metastasis was observed in 9 patients, corresponding to a rate of 22.5%. High-grade tumors were independently associated with a higher risk of occult metastasis compared to low-grade tumors (hazard ratio 1.52, 95% confidence interval 1.17-2.00). cT2 MS-SCC carries an occult metastasis rate of 22.5%, with histologic grade being the primary determinant of occult metastasis. END does not confer a significant survival benefit in this patient population.

Sentinel lymph node biopsy (SLNB) has gained considerable attention in the management of head and neck cutaneous squamous cell carcinoma (HNcSCC). The aim of this study was to compare the oncologic outcomes between observation and SLNB in cN0 high-risk HNcSCC patients. We retrospectively enrolled patients from the SEER database and evaluated the impact of observation versus SLNB on disease-specific survival (DSS) and overall survival (OS) using a Propensity Score Matching (PSM) analysis. A total of 9804 patients were included, with 1169 cases treated by SLNB. Successful retrieval of the sentinel lymph node was achieved in 1130 procedures. After PSM and subsequent multivariate analysis, SLNB was found to be an independent predictor for improved DSS, with a hazard ratio of 0.70 (95

Abstract Background The study aimed to assess the impact of parotid lymph nodes (LNs) on the prognosis of patients with cutaneous squamous cell carcinomas of the head and neck (HNcSCC), and to develop an alternative LN assessment method to enhance locoregional control (LRC) and overall survival (OS) stratification. Methods We retrospectively enrolled patients with surgically treated HNcSCC. Primary outcome variables were LRC and OS. The influence of parotid LNs and different LN assessment methods on prognosis was analyzed using Cox models, and comparisons were made using the C-index, Akaike Information Criterion, and Bayesian Information Criterion. Results A total of 126 patients were included. Both intraparotid and periparotid LN statuses significantly linked with prognosis. The presence of extranodal extension (ENE) in cervical LNs, rather than parotid LNs, was predictive of decreased LRC and OS. In the Cox analysis, only N3 of the AJCC N classification, when compared to N0, showed reduced LRC and OS. In comparison to N0P1, only N0P3/N1P1 and N2P2/N2P3 of the O’Brien staging system tended to predict poorer LRC, with no subgroup emerging as an independent predictor for OS. The proposed LN assessment method, based on the number of metastatic LNs and ENE status in cervical LNs, demonstrated superior performance in terms of C-index, Akaike Information Criterion, and Bayesian Information Criterion compared to other systems. Conclusion Parotid LNs were significant determinants of prognosis in metastatic HNcSCC. The novel LN assessment method proposed (1–2 vs. 3–4 vs. 5 + or ENE) displayed similar survival stratification to the AJCC N and O’Brien staging systems.

OBJECTIVE:To evaluate the oncologic safety and quality of life associated with the use of sentinel lymph node biopsy (SLNB) as compared to elective neck dissection (END) in patients with cT1/2N0 maxillary squamous cell carcinoma. METHODS:This study constituted a retrospective analysis of consecutively treated patients who underwent SLNB or END, with data collected prospectively. We analyzed the impact of the different neck procedures on regional control and disease-specific survival via the Cox model. Patients in both groups completed the University of Washington Quality of Life questionnaire. RESULTS:We included a total of 130 patients, with 47 receiving SLNB. In all cases, the sentinel lymph node could be identified, and of these, 5 had a positive result, yielding a sensitivity of 83.3 %, a specificity of 100 %, a false negative rate of 16.7 %, and a negative predictive value of 97.6 %. The sensitivity, specificity, false negative rate, and negative predictive value of END in detecting occult metastasis were 64.3 %, 100 %, 35.7 %, and 93.2 %, respectively. In comparison to END after propensity score matching, SLNB exhibited no significant difference in its effects on regional control (p = 0.519, HR: 1.05, 95 % CI: 0.52-1.93) and disease-specific survival (p = 0.634, HR: 1.22, 95 % CI: 0.53-1.99). Patients in SLNB group showed significantly higher mean scores of shoulder and taste domains at 3 months, 6 months, and 12 months postoperatively compared to those in END group. CONCLUSION:SLNB could act as a viable alternative to END in cT1/2N0 maxillary squamous cell carcinoma with comparable prognosis and better quality of life.

OBJECTIVE:Our objective is to assess the oncologic outcomes of observation, elective neck dissection (END), and elective neck irradiation (ENI) in the neck management of head and neck cutaneous squamous cell carcinoma (HNcSCC) with parotid metastasis (P+) and to evaluate the quality of life (QoL) of patients who received END or ENI. METHODS:Patients with P+ HNcSCC were retrospectively enrolled. The impact of observation, END, and ENI on regional control (RC) and overall survival (OS) was analyzed using Cox proportional hazards model with presentation via hazard ratio (HR) with a 95% confidence interval (CI). QoL was evaluated using the University of Washington Quality of Life questionnaire. RESULTS:A total of 134 patients were included in our analysis. In the Cox model for RC, both END and ENI had decreased HRs of 0.27 (95% CI: 0.15-0.69) and 0.34 (95% CI: 0.18-0.86), respectively, in comparison with observation. In the Cox model for OS, both END (p = 0.001, HR: 0.22, 95% CI: 0.10-0.72) and ENI (p = 0.006, HR: 0.30, 95% CI: 0.17-0.83) were superior to observation. In patients with three or more positive parotid lymph nodes, END resulted in significantly better RC (p < 0.001) and OS (p = 0.001) compared with ENI. The two groups were found to be comparable in all 12 domains of the University of Washington Quality of Life questionnaire. CONCLUSION:In the neck management of P+ HNcSCC, observation is not recommended. END is the preferred option, but ENI is an alternative method without compromise to survival or QoL, except in cases with three or more metastatic parotid lymph nodes.

OBJECTIVE:To examine the distribution of non-sentinel lymph nodes (SLNs) and to determine the feasibility of omitting elective neck dissection (END) in cases of cT1/2N0 oral cancer presenting with SLN metastasis. METHODS:A prospective cohort of patients with cT1/2N0 oral cancer underwent SLN biopsy using a γ-probe alongside methylene blue staining, followed by subsequent END. The primary outcome variable was non-SLN metastasis, with its predictors evaluated through logistic regression analysis. RESULTS:A total of 200 patients with detectable SLNs were analyzed. Logistic regression revealed a significant odds ratio of 4.28 [95 % confidence interval: 2.11-14.56] for predicting non-SLN metastasis when comparing a depth of invasion greater than 4.0 mm to a DOI of 4.0 mm or less. Among the six cases of non-SLN metastasis, three patients with negative SLN biopsy results exhibited metastasis; one was found in ipsilateral level V and two in contralateral level Ib. In contrast, all three patients with positive SLN biopsy results had a DOI surpassing 4.0 mm, presenting with at least two positive SLNs. Non-SLN metastasis was detected in ipsilateral level III for one patient and at level IV for two others. CONCLUSION:END may be judiciously omitted in cases where only one positive SLN is identified in early-stage oral cancer with a depth of invasion of ≤ 4.0 mm.

This study aimed to assess the impact of the number and ratio of metastatic lymph nodes (LNs) on prognosis in submandibular gland cancer. To this end, patients were selected from the Surveillance, Epidemiology, and End Results database retrospectively. The effect of the number and ratio of metastatic LNs and the American Joint Committee on Cancer (AJCC) N stage on disease-specific survival (DSS) and overall survival (OS) was analyzed. In addition, prognostic models based on LN evaluation methods were developed to predict the OS and DSS. A total of 914 patients were included. Binary recursive partitioning analysis determined the optimal cut-off number of metastatic LNs (0 vs. 1-2. vs. 3+). The presence of 3+ metastatic LNs carried the greatest impact on prognosis, followed by 1-2 positive LNs occurrences. The ratio of metastatic LNs was an independent factor for DSS and OS. The model had a higher likelihood ratio and C-index than those in the Cox model based on the AJCC N stage. Quantitative LN burden and ratio of metastatic LNs provides better survival stratification than the AJCC N stage.

Introduction: Survival significance of parotid lymph node (LN) factors in parotid cancer remains unclear, our goal was to assess the impact of number, size, and extranodal extension (ENE) of metastatic parotid LNs on prognosis in parotid cancer. Materials and methods: Patients with surgically treated parotid cancer were retrospectively enrolled. Primary outcome variable was recurrence-free survival (RFS) and overall survival (OS). The hazard ratios (HRs) of main predictive variables including the number, size, and ENE of positive parotid LNs on RFS and OS were analyzed using Cox model. The secondary outcome variable was ENE of metastatic parotid LN, its association with clinicopathologic variables were evaluated using Chi-square test. Results: In total, 453 patients (186 male and 267 female) were included. The 10-year RFS and OS rates were 73% (95%CI: 69%-77%) and 61% (95%CI: 55%-67%), respectively. In Cox model, compared none parotid LN metastasis, one metastatic parotid LN did not offer additional compromise of RFS (p = 0.224) or OS (p = 0.135), but two or more positive LNs decreased the control of RFS (HR: 2.017; 95%CI: 1.378-4.632) and OS (HR: 2.173; 95%CI: 1.367-4.275). When accounting for the number of metastatic LNs, LN size or ENE was no longer related to RFS or OS. ENE of parotid LN tended to develop if there was presence of T3/4 stage, lymphovascular invasion, high histologic grade, N2/3 stage, and three or more positive parotid LNs. Conclusion: Quantitative parotid LN burden but not ENE or LN size is an important determinant of survival in patients with parotid cancer. (c) 2023 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Objective The aim of this study is to identify the risk factors associated with orocutaneous fistula (OCF) formation after free flap reconstruction for oral squamous cell carcinoma (SCC). Methods Patients undergoing free flap reconstruction for oral SCC were retrospectively enrolled. The relationship between clinicopathologic variables and OCF formation was analyzed by univariate and multivariate analyses. Results A total of 87 OCFs occurred in 856 patients. Univariate analysis revealed cachexia, tumor at the tongue/floor of the mouth (TFOM), T4 stage, preoperative hemoglobin level, pull-through procedure, preoperative albumin level, and surgical site infection were associated with the formation of OCF. Multivariate analysis confirmed the independence of cachexia, TFOM, T4 stage, and surgical site infection in predicting OCF development. Conventional wound care could achieve successful fistula closure in 82.4% of the patients with a median time of 28 days. Conclusions OCF formation was common after free flap reconstruction. The presence of cachexia, TFOM tumor site, T4 stage, and surgical site infection significantly increased the risk of OCF formation. Although it required a long period, conventional wound care can obtain satisfactory outcomes in OCF management.

ObjectiveTo determine predictors of malignancy in surgically treated Bethesda category III nodules.MethodsPatients with surgically treated thyroid nodules classified as Bethesda category III were retrospectively enrolled. The association between clinical/sonographic features and postoperative pathology was evaluated using univariate and multivariate analyses.ResultsA total of 188 nodules from 184 patients were included. The overall malignancy rate was 54.3%. In univariate analysis, male sex, aspect ratio >1, microcalcification, unclear boundary, BRAFV600E mutation, and nuclear atypia were significantly associated with malignant disease in Bethesda category III nodules. Multivariate analysis confirmed that male sex, aspect ratio >1, microcalcification, and BRAFV600E mutation were independent predictors of malignant disease.ConclusionsMalignant disease was common in Bethesda category III nodules, and surgical treatment was strongly indicated in the presence of male sex, aspect ratio>1, microcalcification, and BRAFV600E mutation.

Background Both fine-needle aspiration biopsy (FNAB) and frozen section (FS) examination are reliable methods for assessing cervical lymph node (level II-V) metastasis (LNM) in papillary thyroid carcinoma (PTC). Our goal was to compare the diagnostic accuracy of FNAB and FS in clinically positive neck (cN+) PTC patients. Methods Altogether, 264 lymph node samples from 220 patients were prospectively enrolled. Samples were assessed by FNAB cytology (FNAB-C), thyroglobulin (Tg) FNAB needle wash testing (FNAB-Tg), and FS simultaneously. Diagnostic performance of the different methods were analyzed by the Chi-square test. Results The sensitivity and specificity of FNAB-C alone in predicting LNM was 87.4% and 85.7%, respectively. Combined with FNAB-Tg, the sensitivity and specificity of FNAB-C increased to 98.9% and 81.6%, respectively. The sensitivity and specificity of FS in predicting LNM was 92.4% and 81.1%, respectively. FNAB-C and FNAB-Tg had better sensitivity than FS when applied to solid lymph nodes, and comparable sensitivity when applied to cystic and cystic-solid lymph nodes. Conclusion The utilization of FNAB-Tg significantly improved the diagnostic ability of FNAB-C. FS can be replaced by preoperative FNAB combined with FNAB-Tg without compromising diagnostic accuracy.

Objectives To compare the oncologic outcomes in patients with cT1N0 tongue squamous cell carcinoma (SCC) who underwent different neck management strategies stratified by sonographic depth of invasion (DOI). Methods The included patients were retrospectively enrolled, and divided into two groups: observation (OBS) and elective neck dissection (END). The regional control (RC) and disease-specific survival (DSS) rates were compared and stratified by sonographic DOI. Results The mean sonographic and pathologic DOIs were 3.8 and 3.7 mm, respectively; the two DOIs were significantly correlated (Spearman correlation coefficient 0.974. p <0.001). In patients with sonographic DOI <4.0 mm, the 5-year RC rates were 73 and 89% in the OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year RC rate was significantly different between the OBS (57%) and END (80%) groups (p = 0.031). In patients with sonographic DOI <4.0 mm, the 5-year DSS rates were 79 and 89% in OBS and END groups, respectively, and were not significantly different. However, in patients with sonographic DOI ≥4.0 mm, the 5-year DSS rate was significantly different between the OBS (67%) and END (86%) groups (p = 0.033). Conclusions Sonographic DOI was notably correlated with pathologic DOI. Moreover, there was a significant survival difference between the OBS and END groups in cT1N0 tongue SCC patients with sonographic DOI ≥4.0 mm but not in those with sonographic DOI <4.0 mm. Our study provides a useful method to aid decision-making in the clinical setting for this patient group.