Microscopic positive margins strongly predict reduced disease-free survival in pT4a papillary thyroid cancer

Head Neck. 2019 Aug;41(8):2549-2554. doi: 10.1002/hed.25730. Epub 2019 Mar 12.


Background: Although microscopic positive margins appear to have no independent prognostic impact in papillary thyroid cancer (PTC), this may not be the case in pT4a tumors.

Methods: Retrospective analysis of 610 patients with PTC, 39 with pT4a tumors, to determine if microscopic positive margins impact disease-free survival (DFS) in pT4a PTC.

Results: On univariate analysis, microscopic positive margins were not associated with reduced DFS in patients with no extrathyroidal extension (ETE) (hazard ratio [HR], 1.7; P = 0.32), microscopic ETE (HR, 1.6; P = 0.36), or macroscopic ETE limited to strap muscles (HR, 1.2; P = 0.87). In contrast, microscopic positive margins were associated with reduced DFS in T4a disease (HR, 4.1; P = 0.04). Disease recurrence was nodal, distant, or biochemical, and did not occur directly at the site of positive margins.

Conclusion: Although microscopic positive margins do not influence DFS in the majority of patients with PTC, they are associated with a fourfold increased risk of recurrence in pT4a disease.

Keywords: aerodigestive tract; extrathyroidal extension; papillary carcinoma; positive margins; radioactive iodine; thyroid cancer.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Disease-Free Survival*
  • Female
  • Humans
  • Iodine Radioisotopes / therapeutic use
  • Male
  • Margins of Excision*
  • Middle Aged
  • Neck Dissection
  • Neoplasm Recurrence, Local
  • Prognosis
  • Retrospective Studies
  • Thyroid Cancer, Papillary / mortality
  • Thyroid Cancer, Papillary / pathology*
  • Thyroid Cancer, Papillary / therapy
  • Thyroid Neoplasms / mortality
  • Thyroid Neoplasms / pathology*
  • Thyroid Neoplasms / therapy
  • Young Adult


  • Iodine Radioisotopes