Low Risk

Intermediate Risk

High Risk

Papillary thyroid cancer with all of the following:

• No local or distant metastases

• All the macroscopic tumor has been resected (R0)

• No invasion of local and regional tissues

• The tumor does not have an aggressive histology (aggressive histology’s include high-cell, insular tumors, columnar cell carcinoma, Hürthle cell carcinoma, follicular thyroid cancer, Hobnail variant)

• Without vascular invasion

• There is no uptake of I-131 outside the thyroid bed in the post-treatment examination

• Clinical N0 or ≤5 pathological micro-metastases; N1 (<0.2 cm in the largest dimension)

• Well-differentiated, encapsulated intra-thyroid follicular cancer

• Well-differentiated intra-thyroid follicular thyroid cancer with capsular invasion and zero or minimal vascular invasion (<4 foci)

• Intra-thyroid, unifocal or multifocal papillary micro-carcinoma, including mutated BRAF V600E (if known)

Any of the following present:

• Microscopic invasion of peri-thyroid soft tissues

• Cervical ganglionic metastases or avid I-131 metastatic foci in the neck on post-treatment examination after thyroid bed ablation

• Tumor with aggressive histology or vascular invasion (aggressive histologies include high cell tumors, columnar, insular cell carcinoma, Hürthle cell carcinoma, follicular thyroid cancer, Hobnail variant)

• Clinical N1 or >5 pathological N1 with all affected lymph nodes < 3 cm in the largest dimension

• Multifocal papillary thyroid micro-carcinoma with extra thyroid extension and BRAF V600E mutation (if known)

Any of the following present:

• Macroscopic tumor invasion

• Incomplete tumor resection with macroscopic residual disease

• Remote metastasis

• Postoperative serum thyroglobulin suggestive of distant metastases

• Pathological N1 with any metastatic lymph node ≥ 3 cm in the largest dimension

• Follicular thyroid cancer with extensive vascular invasion (>4 foci of vascular invasion)