Suspicious cervical lymph nodes detected after thyroidectomy for papillary thyroid cancer usually remain stable over years in properly selected patients.

CONTEXT: The risk of loco-regional recurrence in papillary thyroid cancer (PTC) patients ranges from 15-30%. However, the clinical significance of small-volume loco-regional recurrence detected by highly sensitive ultrasonography is unclear.
OBJECTIVE: Our objective was to describe the natural history of abnormal cervical lymph nodes (LN) diagnosed after initial treatment.
DESIGN: We conducted a retrospective cohort study. PATIENTS: 166 PTC with patients who had at least one abnormal LN outside the thyroid be on ultrasound and selected for active surveillance were included. MAIN OUTCOME MEASURE: LN growth during a period of active surveillance was the primary outcome.
RESULTS: Most patients had classical PTC (85%) and an intermediate risk of recurrence (77%). The median LN size at the start of the observation period was 1.3 cm (range, 0.5-2.7 cm) in largest diameter, with all nodes having at least one abnormal sonographic characteristic (70% of patients had LN with at least two abnormal features). In almost all patients, the LN were in the lateral neck, primarily in levels 3 (43%) and 4 (58%). After a median follow-up of 3.5 yr, only 20% (33 of 166) grew at least 3 mm, 9% (15 of 166) grew at least 5 mm, and 14% (23 of 166) resolved. None of the clinical or sonographic features were predictive of LN growth (positive predictive value range = 0.21-0.57). There were no local complications (nerve damage or local invasion) related to the abnormal nodes and no disease-related mortality.
CONCLUSIONS: Suspicious cervical LN in the lateral neck usually remain stable for long periods of time in properly selected PTC patients and can be safely followed with serial ultrasounds.