Case report and literature review: a case of rare papillary thyroid carcinoma combined with paraganglioma.

BACKGROUND: Papillary thyroid carcinoma (PTC) primarily metastasizes to ipsilateral cervical lymph nodes. Paragangliomas (PG) in the head and neck region may be located at the carotid bifurcation, causing anatomical separation of the internal and external carotid arteries. METHODS: A rare case of PTC with PG at our center is reviewed to explore the relationship and differential diagnosis between PG and cervical lymph node metastasis (CLNM) in thyroid carcinoma. Based on the characteristics of this case, we retrieved relevant domestic and international case reports and relevant studies. This study searched the PubMed, Web of Science, and CNKI databases for publications up to March 2026. The search terms included: "Thyroid papillary carcinoma," "Papillary thyroid cancer," "Paraganglioma," "Carotid body tumor," and "Coexistence." By combining these terms, we identified case reports and related studies on papillary thyroid carcinoma with concomitant paraganglioma. RESULTS: We consider the patient's disease type to be PTC with concomitant carotid body tumor. Based on existing clinical data and relevant literature reports, no clear correlation has been established between PGs and CLNMs from thyroid carcinoma. CONCLUSIONS: Distinguishing whether a neck mass associated with thyroid carcinoma represents CLNM or another type of tumor is crucial for disease diagnosis, treatment planning, and prognosis assessment.