Characteristics of cervical lymph node involvement in papillary thyroid carcinoma

Objectives: the aim of this study is to evaluate the relationship between the site of the primary papillary thyroid carcinoma and the level of cervical lymph node metastasis in order to help in future planning of dissection of the most accurate neck levels. Methods: retrospective review of patients with papillary thyroid carcinoma who underwent thyroidectomy either total or partial with neck dissection in our general surgery department during the period between 2011 and 2021. Results: 37 patients were included in our study according to the inclusion and exclusion criteria. The average age was 44± 19.5 years. Female to male ratio was 1.5:1. 20 patients were ≤ 45 years old (54%), while 17 patients were ˃45 years old (46%). The average maximum size of the tumors was 23.2± 17.9mm. 15 patients had multifocal disease (40.5%), while solitary lesions were found in 22 (59.5%). The incidences of lymph node metastasis according to the neck nodal level were 40.5% (15cases) at level Ⅱ, 67.6% (25 cases) at level Ⅲ, 45.9% (17cases) at level Ⅳ, 16.2% (6 cases) at level Ⅴ, and 54% (20 cases) at level Ⅵ. 14 cases (37.8%) had T1 disease, 8 cases (21.6%) had T2 disease, and 15 cases (40.5%) had T3 disease. Conclusion: PTC most frequently metastasizes to level Ⅲ followed by level Ⅵ. Level Ⅲ dissection is usually combined with dissection of level Ⅳ. Most surgeons prefer to do prophylactic dissection of level Ⅵ even with no pre-operative evidence of involvement. Levels Ⅱ and Ⅴ are not routinely performed unless there is clinical/ radiological evidence of involvement.