Dr. González, PhD.
Hospital Vall d’Hebron, Barcelona, Spain.
Dr. Balibrea, PhD.
Hospital Clinic, Barcelona, Spain.

Lymphadenectomy in papillary thyroid carcinoma (PTC) is controversial. Up to 50% of cN0 patients become pN1 postoperatively, therefore a prophylactic lymphadenectomy can be considered in high-risk patients.
One-step nucleic acid amplification (OSNA) is a molecular technique that enables real-time detection of mRNA encoding for cytokeratin 19. It was initially developed for the intraoperative assessment of sentinel lymph node metastases in breast cancer. Recent studies demonstrate that OSNA can be used as an alternative method to pathological assessment for examining lymph node metastasis in other tumors. This technique has been introduced in intraoperative analysis of several tumors to reduce false-negative rates and distinguish micrometastasis from macrometastasis in order to select patients who would benefit from a lymphadenectomy and spare the risk to those who would not. It is a quantitative method, providing a thresholding of nodal involvement.
In this video Dr. González and Dr. Balibrea perform a total thyroidectomy with intraoperative OSNA determination followed by a lymphadenectomy due to a positive result.