Research in Medicine

Background: Despite the long-term survival in papillary thyroid cancer (PTC), cervical lymph node metastasis is the most important factor in regional recurrence of the disease. The aim of the present study was to find clinical risk factors for microscopic metastasis to the lymph nodes, without involvement of the neck lymph nodes.

Methods: medical records of 115 PTC patients who underwent total thyroidectomy surgery in Ayatollah Taleghani Hospital of Tehran during 2015-2016. Study variables included age, gender, tumor size, multifocality of tumor, tumor location and tumor extension to thyroid capsule, and metastasis. Data were analyzed using SPSS v20 software.

Results: The incidence of metastasis was 49%. A weak positive correlation was observed between age and metastasis, and a very weak correlation between the tumor size and metastasis. The calculated cut-off point for age was 42.5 years  and for tumor size, 1.75 cm (sensitivity 58% and specificity 57%). The metastatic was more common in men than women and in the multifocal tumors than single focal tumors. Metastasis was associated with tumor location and tumor extension to the thyroid capsule.

Conclusion: It seems that older age, larger tumor size, male gender, multifocal tumor, extension of tumor invasion to the capsule could be predictive risk factors of lymph node metastasis in PTC patients, and therefore, prophylactic central lymph node dissection may be considered in the patients who have several of these factors. Also, post-operative follow-up for recurrence should be performed more accurately and in a shorter time interval in these patients. However, more studies should be done in the future.