Positive Sentinel Lymph Nodes are a Negative Prognostic Factor for Survival in T1-2 Oral/Oropharyngeal Cancer—A Long-Term Study on 103 Patients

Background To evaluate prognostic value of sentinel node biopsy (SNB) in oral/oropharyngeal squamous cell cancer (OOSCC) concerning overall/disease-free survival. Methods One hundred three consecutive patients with T1-2N0 OOSCC were consecutively recruited for SNB as single invasive staging method for the neck. Two hundred seventy-three sentinel nodes (SNs) were removed (mean, 2.65 per patient). Nine patients had 10 positive SNs (upstaging rate, 8.7%) found in levels I to III, leading to a therapeutic neck dissection. Results Mean observation time of all patients was 6.7 years; mean survival time of patients with negative or positive SNs was 6.9 and 3.7 years, respectively. There has been no false-negative result of SNB to date becoming manifest in ipsilateral node metastasis during follow-up. Five-year overall/disease-free survival of all patients was 82%/72%, respectively. The same parameters for the patients with negative SNs were 85%/74%, for those with positive SNs 38%/47%, respectively (statistically significant). There has been a higher statistical risk for locoregional recurrence for patients with positive SNs. Rates of metachronous second primary tumors developing during follow-up were 10.6% (negative SNs) and 44.4% (positive SNs). Conclusion SNB was a valuable diagnostic method in patients with T1-2N0 OOSCC avoiding elective neck dissections. Patients with positive SNs had statistically significantly higher rates of locoregional recurrences, second primary tumors, tumor-related deaths, and a worse overall/disease-free survival. To date, no therapeutic consequences in case of a positive SN beyond execution of modified radical neck dissection (to remove other positive nodes) and closer attention during follow-up can be concluded from this study.