Funding for this research was provided by:
grant from the BeijingHospitals Authority Youth Programme (QML20181805)
Received: 13 October 2019
Accepted: 4 March 2020
First Online: 14 March 2020
Ethics approval and consent to participate
: The study protocol was approved by Ethics Committee of Beijing Ditan Hospital, Capital Medical University. FNAC was done on all patients after a brief explanation of the technique and an informed written consent was taken.
: Not applicable.
: The authors declare that they have no competing interests.