Objectives: The aim of this study was to determine the incidence, predictors, and outcomes of cervical lymph node metastases in patients with pT1-2 oral tongue squamous cell carcinoma (OTSCC).
Materials and Methods: A total of 166 patients with OTSCC were treated at our department from January 2018 to December 2020. Of the 180 patients, 148 were classified as pT1-2 (pT1 113, pT2 35) and were included in the analysis. Patients with multiple head and neck cancers and treated postoperative chemotherapy and/or radiotherapy were excluded. Clinicopathological information was obtained from medical charts. Furthermore, we performed multiplex immunofluorescence staining for CD8 and FoxP3 in pT2 patients and analyzed the localization of CD8 and FoxP3.
Results: Among 148 patients with pT1–2, 24 patients (pT1, 14/113; pT2, 10/35) were diagnosed with cervical lymph node metastasis. Univariate analysis showed that an INF classification of c, pDOI >3.0 mm, and venous invasion were significantly associated with cervical lymph node metastasis (P = 0.002, P < 0.001, and P = 0.006, respectively). In multivariate analysis, pDOI >3.0 mm remained an independent risk factor for cervical lymph node metastasis (OR, 5.573; 95% CI, 1.517–20.781; P = 0.009). The multiplex immunofluorescence staining showed that the intratumoral-to-peritumoral ratios for CD8+ density were significantly higher in the pN+ group than in the pN- group (P = 0.011).
Conclusion: In early-stage OTSCC, pDOI >3.0 mm and a higher intratumoral-to-peritumoral CD8+ density ratio are associated with cervical lymph node metastasis.