Sonographic features of papillary thyroid microcarcinoma predicting high-volume central neck lymph node metastasis.

•Study of the preoperative ultrasound characteristics of 2363 patients with surgically resected papillary microcarcinoma.•A high number of metastatic neck lymph nodes (>5) has been associated with the recurrence of PTC.•The preoperative ultrasonic features of microcalcifications, larger tumour size (>7 mm), and capsule invasion were independent risk factors for high-volume lymph (>5) node metastasis in the central compartment of PTMC.