Nodular metastatic lung tumor from thyroid carcinoma

Lung metastasis from thyroid cancer: A case report of unusual imaging presentation of lung metastases

RATIONALE

Thyroid cancer (TC) is the most common malignancy of the head and neck and endocrine system. Distant metastases from TC are rare and are diagnosed in only 1% to 4% of patients, and these patients have a poor prognosis, which is the leading cause of TC-related deaths. There are few reports on metastatic TC in China and abroad, and even fewer reports on lung metastases from TC. We report a special patient with lung metastases of TC.

PATIENT CONCERNS

The patient is a 31-year-old female who was found to have both lung nodules during physical examination. Chest computed tomography (CT) showed that the density of both lung nodules was the same as the vascular density, considering that the possibility of vascular origin was not excluded.

DIAGNOSIS

After consultation with the whole hospital, it was considered that vascular malformations, hemangiomas, and malignant metastases were not excluded, the patient percutaneous lung biopsy had a high risk of bleeding, and thoracoscopic lobectomy could be performed in thoracic surgery to further clarify the pathology and diagnosis.

OUTCOMES

The patient underwent thoracoscopic left lower lobe wedge resection on February 24, 2021. Postoperative pathology: (left lower lung mass) metastatic carcinoma, combined with morphology and immunohistochemistry, leaning toward thyroid follicular carcinoma lung metastasis. On May 27, 2021, the patient underwent "total thyroidectomy + lymph node dissection in the right cervical VI region." Pathological examination: (right lobe and isthmus of the thyroid gland) papillary TC, follicular subtype, and classic type, with interstitial fibrosis. The patient was diagnosed with lung metastasis of TC.

LESSONS

This patient had the same CT value of lung metastases as the vascular CT value, which is relatively rare in our clinical practice and worthy of our study. The special CT imaging presentation of this TC patient with lung metastases further broadened our horizon. In clinical practice, when we encounter similar cases, we should combine more with other tests and examinations of patients to avoid misdiagnosis and missed diagnosis.

Lung Metastasis from Thyroid Carcinoma Showing a Pure Ground-glass Nodule

We report a rare case of lung metastasis of thyroid carcinoma showing a pure ground-glass nodule in a 68-year-old man who underwent total thyroidectomy and lymph node dissection in 2004. We followed the nodule growth, found 5 years after the surgery in the right lower lobe, using computed tomography and observed a gradual enlargement to 8 mm in 11 years. Postoperative pathology and immunohistochemistry revealed that the tumor was a papillary carcinoma that metastasized from the thyroid. This report may help clinicians recognize pure ground-glass nodules as lung metastasis of thyroid carcinoma and avoid misdiagnosis as lung adenocarcinoma.