Sentinel lymph node biopsy may be used to support the decision to perform modified radical neck dissection in differentiated thyroid carcinoma.
BACKGROUND
The prognostic significance of lymph node metastases (LNM) in follicle cell-derived differentiated thyroid carcinoma (DTC) is still controversial. The management of cervical lymph nodes varies from "berry picking" to modified radical neck dissection (MRND). The incidence of LNM in papillary thyroid carcinoma varies from 27% to 80%. The importance of sentinel lymph node (SLN) biopsy for decisions about the surgical management of lymph nodes in DTC has been the subject of several previous studies.


METHODS
In 40 patients with DTC methylene blue dye was applied peritumorally. Both SLN and non-SLN in the lower third of the jugulo-carotid chain were dissected prior to total thyroidectomy and routine dissection of the central neck compartment and examined by frozen-section and standard histology. MRND was performed in 9 cases of LNM in the lateral neck compartment.


RESULTS
The SLN identification rate was 92.5%. Metastases in SLNs were revealed by frozen-section histology in 7 cases, leading to immediate MRND. The findings were confirmed on standard HE examination. In 2 false-negative cases SLN metastases were revealed on standard histology and MRND was performed 1 week later. The specificity of the method was 100%, sensitivity 77.7%, negative predictive value 94%, positive predictive value 100%, with overall accuracy of 95%.


CONCLUSIONS
Our results seem to imply that SLN biopsy in the jugulo-carotid chain using methylene blue dye mapping may be a feasible and valuable method for estimating lymph node status in the lateral neck compartment. It may be helpful in the detection of true-positive but nonpalpable lymph nodes, and in such cases may support the decision to perform MRND in patients with DTC.
Dzodic
Radan
R
Medical School University of Belgrade, Institute of Oncology and Radiology of Serbia, National Cancer Research Center, Pa sterova 14, 11000, Belgrade, Serbia and Montenegro. radan@ncrc.ac.yu
Markovic
Ivan
I
Inic
Momcilo
M
Jokic
Neven
N
Djurisic
Igor
I
Zegarac
Milan
M
Pupic
Gordana
G
Milovanovic
Zorka
Z
Jovic
Viktor
V
Jovanovic
Nikola
N