Radiologic Findings of Occult Nodal Metastasis During Clinically N0 Salvage Laryngectomy

Introduction: The presence of occult nodal disease (OND) during clinically node negative salvage total laryngectomy (TL) is an important predictor of survival. Currently, the Neck Imaging Reporting and Data Systems (NI-RADS) is a reliable method for recurrence detection in these patients. However, a subset of patients will still have OND revealed on final pathology. The goal of this study is to retrospectively evaluate their preoperative imaging for suspicious features.

Methods: A retrospective review was performed on patients who had OND during salvage TL with elective neck dissection (END) between 2009 and 2021 at a single, high-volume center. Collected and analyzed data included demographics, TNM staging, nodal disease presence and location, and preoperative images and interpretation by a neuro and nuclear medicine radiologist.

Results: Among 81 salvage TL patients undergoing END, 13 (16%) had pathologic OND. Twenty-seven pathologic nodes were evaluated, and 48% (13 of 27) had extranodal extension. The average node length was 0.6 cm, and 15% (4 of 27) of nodes were ≥1cm. All patients underwent a preoperative CT/MRI with contrast and PET scan, and most (12 of 13) were within 8 weeks of surgery. On CT/MRI review, 33% (9 of 27) pathologic nodes had rounded morphology. Except for 3 nodes that were 1cm in length, the rest were < 1cm. One patient scored NI-RADS 2 (low suspicion of recurrence), and the rest scored 1 (no suspicion). PET review revealed 1 suspicious node, but the remainder had SUVs below blood pool.

Conclusions: Among patients undergoing an END during salvage TL, 16% had pathologic OND. On preoperative imaging, pathologic nodes were very subtle and challenging to identify. Despite no clear impact on survival, performing an END may provide prognostic information for these patients.