Papillary thyroid cancer with suspicious uterine cervix metastasis: a case report and literature review

Abstract

Background: Distant metastasis (DM) of papillary thyroid cancer (PTC) is rare but significantly associated with decreased survival. Accurate clinical staging at initial diagnosis and during follow-up is essential.

Case description: We report the case of a 38-year-old woman diagnosed with PTC in the left isthmus who presented with a suspicious uterine cervix metastasis during follow-up after total thyroidectomy. She had neither medical history nor family history of thyroid cancer. During surgery, extensive central node metastases were found, and bilateral total thyroidectomy was performed. Even after three rounds of radioactive iodine (RAI) ablation, persistently elevated serum thyroglobulin (Tg) levels, combined with a suspicious finding on the whole-body scan (WBS) and fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT), led to the clinical suspicion of uterine cervix metastasis from PTC. Hysterectomy confirmed the pathology of chronic cervicitis. No hidden malignancy was observed. After surgery, negative imaging findings and decreased serum Tg levels were observed.

Conclusions: This case contributes to the discussion of differential diagnostic problems in the setting of clinical and pathological investigations of PTC. However, based on the relevant rationales, through multidisciplinary discussion, this patient can ultimately obtain a better prognosis. Understanding the pitfalls of imaging modalities and continuous efforts to overcome the limitations of the diagnostic process are crucial for future treatment.

Keywords: Papillary thyroid cancer (PTC); case report; distant metastasis (DM); uterine cervix.

Figure 1

Histopathological findings of PTC. (A) Gross examination of isthmic tumor. An ill-defined, firm, whitish mass with close resection margins (colored as blue ink). (B) Microscopic examination of papillary microcarcinoma revealed enlarged nuclei with clear chromatin, arranged in complex papillae with fibrovascular cores (H&E stain, ×200). (C) Extrathyroidal extension of tumor (H&E stain, ×40). (D) D2-40 immunohistochemistry highlights lymphatic emboli (×200). PTC, papillary thyroid cancer; H&E, hematoxylin and eosin.

Figure 2

Images of focal uptake in the uterine cervix at 11 months after total thyroidectomy for PTC. All arrows indicate the increased focal uptake in the uterine cervix. (A) Fused radioiodine SPECT/CT image in axial view. (B) Fused radioiodine SPECT/CT image in sagittal view. (C) Fused ¹⁸F-FDG PET/CT image in axial view. (D) Fused ¹⁸F-FDG PET/CT image in sagittal view. PTC, papillary thyroid cancer; SPECT/CT, single-photon emission computed tomography/computed tomography; ¹⁸F-FDG PET/CT, fluorodeoxyglucose positron emission tomography/computed tomography.

Figure 3

Serum level trends of TSH, Tg, and Tg Ab in the patient following total thyroidectomy. RAI, radioactive iodine; GY op, gynecologic operation; Preop, preoperative; Postop, postoperative; wk, week; mo, month; TSH, thyroid stimulating hormone; Tg, thyroglobulin; Tg Ab, thyroglobulin antibody.

Figure 4

Histological findings of uterine cervix with chronic nonspecific inflammation and squamous metaplasia (H&E stain, ×100). H&E, hematoxylin and eosin.

Figure 5

Images of resolved uptake in the uterine cervix at 26 months after total thyroidectomy for PTC. (A) Fused ¹⁸F-FDG PET/CT image in axial view. (B) Fused radioiodine ¹⁸F-FDG PET/CT image in sagittal view. PTC, papillary thyroid cancer; ¹⁸F-FDG PET/CT, fluorodeoxyglucose positron emission tomography/computed tomography.