Does volumetric measurement of cervical lymph nodes serve as an imaging biomarker for locoregional recurrence of oral squamous cell carcinoma?

Introduction: Recent studies highlighted the prognostic superiority of lymph node volume towards the conventional N Classification. However, data on the importance of neck lymph node volume, obtained by semiautomatic segmentation of CT images, do not exist for locoregional recurrence in patients with oral squamous cell carcinoma (OSCC).

Methods: Retrospective chart review of 100 patients, who were diagnosed and treated between 2006-2014. Inclusion criteria were patients with treatment-naive oral squamous cell carcinoma and primarily curative intended surgery with negative resection margins, for whom a preoperative computed tomography (CT) of the head and neck region was performed. Furthermore, comprehensive neck dissection (level I-V) due to ipsilateral lymph node metastasis was chosen as inclusion criterion. Exclusion criteria were neoadjuvant chemoradiotherapy, T4b classification, perioperative death, unresectable disease, synchronous malignancy, follow-up < 3 months and inadequate information to correctly determine clinicopathological characteristics.

Results: Pathological N Classification (p = 0.001), central necrosis (p = 0.008) and lymph node volume (p < 0.001) significantly affected locoregional recurrence (p < 0.001). Multivariate analysis indicated N Classification (p = 0.06) and volume (p < 0.001) as indepedent risk factors for locoregional recurrence.

Conclusion: Volumetric measurement serves as a better risk stratification tool than the conventional N Classification for OSCC. A lymph node volume of more than 6.86 cm goes along with a 20-fold higher risk for locoregional failure.