Endocrine Abstracts

Aim: Thyroid papillary carcinomas smaller than 1 cm are called papillary microcarcinomas (PMC). They rarely metastasize to lymph node (LN) and distant areas. The presence of palpable lymphadenopathy at the time of diagnosis shows high risk of recurrence regardless of primary tumor size. We aimed to investigate histopathologic characteristics and recurrence frequency of thyroid PMCs with LN metastasis (LNM).

Materials and methods: Thyroid PMC cases with LNM that were followed by our department between 2009 and 2013 were evaluated retrospectively.

Result: There were eight patients (one male, seven females) and the average age was 41 years. The initial compliant was neck lump in four patients, three were already followed-up for thyroid nodule and one for parathyroid adenoma. All were undergone total thyroidectomy and neck dissection. All had received radioactive iodine treatment. None had a history for neck radiotherapy or thyroid carinoma in their family.

The tumor diameter was ≥5 mm in 75% of patients. The smallest one was 2 mm and the largest one was 9 mm in the diameter. Seven of eight patients had LNM at the time of diagnosis and the other had LNM during follow-up. 25% of patients had lymphovascular invasion, 37% had capsular invasion, and 50% had multifocality. None had extrathyroidal spread. 75% of patients had recurrence during follow-up. 83% of those patients had LNM at the time of diagnosis. 71% of the patients who had LNM at the time of diagnosis had recurrence (Table 1).

Conclusion: Thyroid PMCs generally have a good prognosis. They rarely show recurrence. However, the presence of LNM at the time of diagnosis is the most important factor for recurrence risk.