Purpose: In papillary thyroid carcinoma (PTC) patients with mediastinal lesion and lung metastases, adding preoperative computed tomography (CT) to ultrasound aids in determining surgical procedures. We identified the risk factors (RFs) of mediastinal lymph node metastasis (MLNM) and lung metastasis in PTC patients who benefit from CT.
Methods: The frequency of MLNM and lung metastasis was compared using data from 478 patients. Relative risk (RR) was calculated according to RFs.
Results: MLNM or lung metastasis was detected in 1.2% and 3.3%. cT3-4, cN1, central LN metastasis, and lateral LN metastasis were RFs of MLNM in all patients (p<0.05, p<0.05, p<0.05, p<0.01) and those ≥55 years old (older patients) (p<0.01, p<0.05, p<0.05, p<0.05). cT3-4, cN1, gross extrathyroidal extension, central LN metastasis, and lateral LN metastasis were RFs of lung metastasis in all patients (p<0.01, p<0.05, p<0.01, p<0.01, p<0.01). cN1 and gross extrathyroidal extension, central LN metastasis, and lateral LN metastasis in older patients (p<0.01, p<0.01, p<0.05, p<0.01) and lateral LN metastasis in those <55 years old (younger patients) (p<0.05) were RFs of lung metastasis. The RRs of patients with cT3-4 and cN1 were 16.8 (95% confidence interval [CI]: 2.9-97.5) in all patients and 28.7 (95% CI: 3.1-261.4) in older patients for MLNM and 4.4 (95% CI: 1.5-13.3) in all patients, 2.55 (95% CI: 0.3-20.6) in younger patients, and 5.6 (95% CI: 1.5-21.5) in older patients for lung metastasis.
Conclusion: PTC patients with cT3-4 and cN1 have a risk of MLNM and lung metastasis. RFs differed between older and younger patients.