The Benefit of Postoperative Radiotherapy and Extending Neck Dissection in pT1-2 Oral Squamous Cell Carcinoma With a Single Ipsilateral Cervical Lymph Node Metastasis (pN1)

Background/Aim: We compared postoperative radiotherapy (PORT) to surgery only (SO), and supraomo hyoidal neck dissection (SOHND) to modified radical neck dissection (MRND) in patients with pT1-T2 squamous cell carcinomas of the oral cavity (OSCC) and a single cervical lymph node metastasis (pN1) in terms of overall survival (OS), oral cancer specific survival (OCSS), and regional recurrencefree survival (RRFS), in a prospective cohort study. Patients and Methods: We included patients with pT1-T2 pN1 OSCC with no distant metastasis and estimated the survival probabilities using the Kaplan-Meier method and calculated hazards ratios (HR) for PORT vs. SO and MRND vs. SOHND using adjusted Cox regression models. Results: A total of 51 patients (26 SO vs. 25 PORT, 9 SOHND vs. 42 MRND) were evaluated. Patients who received PORT were more likely to be younger and healthier. OS at 5 years was 41% and 87% in the SO and PORT groups, respectively. OS at 5 years was 52% and 67% in the in the SOHND and MRND groups, respectively. Both OCSS and RRFS were improved by PORT. Extending neck dissection was not associated with improved OS (HR = 0.83). Conclusion: PORT is associated with preferable OS, OCSS, and RRFS in pT1-2 pN1 oral cancer and should be recommended regularly.