Sentinel Node Investigation in Patients With Highly Differentiated Papillary Thyroid Carcinoma and in Patients With Thyroid Neoplasia of Unclear Malignant Potential
The standard surgical treatment for highly differentiated papillary thyroid cancer > 10 mm
according to recent national and international guidelines, is total thyroidectomy and
central lymphnode clearance, and for patients with cytology indicating thyroid neoplasia of
unclear malignant potential hemithyroidectomy on the side of the tumour.
There are however a number of clinical problems with these approaches:
- For patients with papillary thyroid cancer, a significant proportion will receive
unnecessary extensive surgical treatment
- In papillary thyroid cancer, central lymphnode clearance increases the risk for
complications, especially the risk for hypoparathyroidism.
According to a Scandinavian survey (Scandinavian Quality Register for Thyroid- and
Parathyroid Surgery; www. thyroid-parathyroidsurgery.com),16 % of patients with unclear
follicular neoplasia, will have a final histological diagnosis of thyroid cancer, and in
half of them, this cancer will be of the papillary subtype. In patients with preoperatively
suspected, but not proven malignancy by cytology, 30 % will receive a final histological
diagnosis of thyroid cancer, and in these patients, 70 % will be of the papillary subtype.
Typically these patients will undergo a second operation with a contralateral
hemithyroidectomy. In many cases, due to risk for complications, central lymphnode clearance
is avoided in these cases. Therefore, the staging of the cancer will be incomplete, and some
patients will receive suboptimal surgical treatment.
The study is designed to compare SN investigation with the final histology of the central
- Pretracheal and bilateral paratracheal for patients with preoperatively diagnosed
papillary thyroid cancer
- Pretracheal and ipsilateral paratracheal for tumours of uncertain malignant potential
The identification of SN will be aided by preoperative ultrasound guided injection of 99m-
Tc- nanocolloid albumin in the thyroid tumour. The results of the histological investigation
of SN will be compared to that of the results from the central lymphnode clearance.
Observational Model: Cohort, Time Perspective: Prospective
Sensitivity and specificity of SN histology compared with the final histology of the non SN central lymph nodes (metastasis or no metastasis)
The histological investigation of the sentinel lymph node(s) (recorded as metastasis or no metastasis), will be compared to the definitive histological investigation of the non SN central lymphnodes (metastasis or no metastasis), cleared by surgery. Sensitivity and specificity of the histological SN investigation to predict the histological outcome of the non SN central lymphnodes (metastasis or no metastasis), will be calculated.
Anders Bergenfelz, MD, PhD
Department of Surgery, Skåne University Hospital, Lund
Sweden: The National Board of Health and Welfare