Regional metastatic pattern of papillary thyroid carcinoma.

The objective of the present study was to determine the pattern of lymphatic spread in papillary thyroid carcinoma with clinically positive nodes. Between 1999 and 2008, a total of 48 consecutive patients with clinical evidence of cervical lymph node metastasis of papillary thyroid carcinoma underwent 61 modified radical neck dissections (13 being bilateral) including levels II-VI. All neck dissection specimens were separated during surgery into levels and analysis was done with respect to the levels of neck. T value of tumor and demographic parameters were compared with the number of metastatic nodes with univariate analysis. The median number of pathologic nodes in neck dissection specimen was 7.0. The predominant site of metastasis was level VI (77%), followed by level III (69%), level IV (66%), and level II (46%). Level V showed 34% of nodal metastasis. Seven patients had level VII, and five patients had parapharyngeal lymph node dissections because of lymphatic involvement at these sites. There was no statistically significant correlation between T value, age, sex and the number of histologically positive lymph nodes (P = 0.39, P = 0.91 and P = 0.84, respectively). It was concluded that the high incidence of metastatic disease in levels II through VI supports the recommendation for level II through level VI neck dissection in patient with clinically positive neck disease.