Preoperative Circulating Tumor Cells (CTCs) Positivity is Associated with Lymph Node Metastasis in Patients with Unifocal Papillary Thyroid Microcarcinoma (PTMC)

Haifeng Zhong, Qingxin Zeng, Yuedong Wang, Jiwei Chen Department of Thyroid Surgery, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of ChinaCorrespondence: Jiwei Chen, Department of Thyroid Surgery, Meizhou People’s Hospital, Meizhou Academy of Medical Sciences, Meizhou, People’s Republic of China, Email [email protected]: To explore the relationship between the preoperative level of circulating tumor cells (CTCs) and lymph node metastasis in patients with unifocal papillary thyroid microcarcinoma (PTMC) (only one independent lesion, diameter ≤ 1 cm), and to clarify the value of preoperative CTCs detection in assessing the risk of lymph node metastasis in patients with unifocal PTMC.Methods: Clinical records (age, gender, Hashimoto’s thyroiditis, thyroid function, invaded capsule, clinical stage) of 370 unifocal PTMC patients were collected retrospectively. The CTCs levels of the patients were measured. The preoperative CTCs positive rate between patients with and without lymph node metastasis were compared; logistic regression analysis was used to explore whether the preoperative CTCs positivity is an independent risk factor for lymph node metastasis.Results: A total of 207 (55.9%) unifocal PTMC patients presented with preoperative positive CTCs (≥ 8.7 FU/3mL), whereas 163 cases (44.1%) were identified as CTCs negative (< 8.7 FU/3mL). The patients with lymph node metastasis had higher proportions of invaded capsule (35.8%% vs 25.2%, p=0.037), and preoperative CTCs positivity (64.2% vs 52.0%, p= 0.033) than patients without lymph node metastasis. Logistic regression analysis shows that preoperative CTCs positivity (odds ratio (OR): 1.654, 95% confidence interval (CI): 1.040– 2.631, p=0.033), and invaded capsule (OR: 1.652, 95% CI: 1.020– 2.677, p=0.041) were associated with lymph node metastasis in patients with unifocal PTMC.Conclusion: Preoperative CTCs positivity (≥ 8.7 FU/3mL) and invaded capsule are associated with lymph node metastasis in unifocal PTMC. Preoperative CTCs detection can serve as an important auxiliary indicator for evaluating the lymph node metastasis potential of patients with unifocal PTMC, thereby providing valuable reference evidence for clinicians to formulate individualized surgical plans and postoperative follow-up strategies.Keywords: circulating tumor cell, unifocal, papillary thyroid microcarcinoma, lymph node metastasis