Elective neck dissection in papillary thyroid carcinoma patients.

BACKGROUND

This study was designed to review the diagnostic performance of cervical lymph node metastases for assessment of elective neck dissection in papillary thyroid carcinoma patients and to determine the technique (using Methylene blue dye) that demonstrated the highest success rate with regard to the detection rate and sensitivity.

METHODS

Preoperative 24 h, 1 mL of 1.0% methylene blue was injected into the parenchyma surrounding the primary tumor with ultrasound guidance by a 27-gauge needle. Intra-operative lymph nodes that were stained blue and/or having afferent lymphatic channels stained blue were also considered to be excised. All stained blue nodes were defined by levels, number, site and were sent for frozen and permanent section histologic analysis.

RESULTS

For the 132 patients who underwent methylene blue dye, 1373 lymph nodes were removed. 7 lymph nodes had negative dye results but, in the end, had metastatic lymph nodes. 120 lymph nodes had both negative dye and lymph node results. The number of blue-dye lymph nodes was 1246 and the number of pathology metastatic nodes was 1079, so the pathological diagnose accordance rate was 87.8 percent. The nodal metastases often occur at level VI, IV, III, then in level II, and less in level I and V.

CONCLUSIONS

This method using methylene blue dye is feasible technically and is safe, and the findings correlate with cervical lymph node status. According to the pattern of blue dye lymph nodes and frozen-section histologic analysis, performing elective neck dissection is a reliable, safe surgical procedure for PTC.