Patterns and Predictors of Cervical Lymph Node Metastasis in Parathyroid Carcinoma

Area of Science:

• Endocrinology
• Oncology
• Surgical Oncology

Background:

• Parathyroid carcinoma (PC) is a rare endocrine malignancy with a high recurrence and metastasis rate.
• The role of cervical lymph node dissection (LND) in managing PC remains unclear.
• Over 60% of PC patients experience disease recurrence or metastasis.

Purpose of the Study:

• To investigate risk factors for recurrence and metastasis in parathyroid carcinoma.
• To evaluate the significance of cervical lymph node dissection in PC management.
• To identify predictors for lymph node metastasis in PC patients.

Main Methods:

• Retrospective review of 68 PC patients diagnosed between 1992 and 2021.
• Systematic collection of clinical data, including histological staging, parafibromin staining, Ki67 index, and CDC73 gene mutation status.
• Analysis of risk factors for recurrence, lymph node metastasis, and distant metastasis.

Main Results:

• Cervical lymph node metastasis was present in 19.4% of patients initially and 25.0% with reoperations.
• A Ki67 index ≥ 5% was an independent risk factor for PC recurrence (HR 4.41).
• High-risk Schulte staging and CDC73 abnormalities were risk factors for cervical lymph node metastasis.

Conclusions:

• While most PCs are slow-growing, lymph node metastasis is not uncommon.
• Distant metastasis is an independent poor prognostic factor for overall survival.
• Central LND is recommended for PC patients undergoing remedial surgery with high-risk Schulte staging or CDC73 abnormalities.