THE DELPHIC LYMPH NODE AND THYROID CANCER
Named after the oracle of Delphi, the Delphic (or prelaryngeal) lymph node has long been regarded as a predictor of malignancy in thyroid cancer. It also has a notorious reputation for being a marker of advanced nodal disease. There is no current medical literature to support or refute these claims. The aim of this study was to determine the true significance of Delphic lymph node involvement in thyroid cancer. Methods
1,000 consecutive patients undergoing total thyroidectomy formed the study population. All information was obtained from a prospectively maintained database as well as from review of the histopathology records. Results
227 of 1,000 (22.7%) had a final diagnosis of thyroid cancer. In 63 of 227 (27.8%), the final diagnosis of cancer was unsuspected. The Delphic lymph node was removed in 112 of 227 patients, with 22 of 112 cancerous. Thus, 19.6% of patients had involvement of the Delphic lymph node when it was removed. Delphic node involvement was associated with significantly greater nodal disease (10.1 vs 1.4 nodes; p < 0.05). No patient in either group had Delphic node involvement diagnosed on clinical grounds preoperatively. Conclusion
Despite its reputation, the Delphic lymph node is not itself an independent predictor of the presence of thyroid cancer. It is however a useful marker of extensive local nodal disease. Identifying intra-operatively whether the Delphic node is involved may assist in planning the extent of neck dissection during total thyroidectomy.
Document Type: Research Article
Publication date: 2007-05-01