Predicting Radiotherapy Necessity in Tongue Cancer Using Lymph Node Yield.
Zhien Feng1, Qiao Shi Xu2, Li Zheng Qin3
1Associate Professor, Department of Oral and Maxillofacial-Head and Neck Oncology, Beijing Stomatological Hospital, Capital Medical University, Beijing, China.
Summary
A lymph node yield (LNY) of less than 20 in patients with tongue cancer and a single metastatic lymph node (pN1) indicates a benefit from adjuvant radiotherapy. This finding helps identify patients who may require further treatment for improved survival outcomes.
Area of Science:
- Head and Neck Oncology
- Surgical Pathology
- Radiation Oncology
Background:
- The prognostic significance of lymph node yield (LNY) in head and neck cancer, particularly in cases with a single metastatic lymph node (pN1), remains debated.
- Accurate identification of patients who benefit from adjuvant radiotherapy is crucial for optimizing treatment strategies in oral tongue squamous cell carcinoma.
Purpose of the Study:
- To evaluate the role of LNY in predicting the adequacy of neck dissection.
- To determine the association between LNY and the need for adjuvant radiotherapy.
- To assess the impact of LNY on 5-year disease-specific survival in patients with pN1 oral tongue squamous cell carcinoma.
Main Methods:
- A retrospective cohort study was conducted on 141 patients with pN1 oral tongue squamous cell carcinoma.
- Lymph node yield (LNY) was analyzed as the primary predictor variable.
- Receiver operating characteristic (ROC) curve analysis was used to determine the optimal LNY cutoff for predicting the need for adjuvant radiotherapy, alongside bivariate statistics for survival analysis.
Main Results:
- An LNY cutoff of 20 demonstrated significant discriminatory power (AUC = 0.708, P = .0001) for identifying patients who would benefit from adjuvant radiotherapy.
- Patients with an LNY < 20 who received adjuvant radiotherapy showed significantly improved 5-year disease-specific survival compared to those who did not (58.0% vs. 21.0%, P = .021).
- No significant difference in 5-year disease-specific survival was observed between low and high LNY groups when adjuvant radiotherapy was not considered.
Conclusions:
- A lymph node yield (LNY) of less than 20, specifically at levels I to III of the neck dissection, is a significant predictor of benefit from adjuvant radiotherapy.
- This LNY threshold can aid in treatment decisions for patients with tongue cancer and pN1 neck status, especially in the absence of other adverse histopathologic features.
- The findings support the use of LNY as a prognostic indicator to guide the necessity of adjuvant radiotherapy in select head and neck cancer patients.
