Cutaneous Implantation Metastasis of Papillary Thyroid Carcinoma Following Fine Needle Aspiration Biopsy

Subcutaneous implantation of nodular goiter after transoral endoscopic thyroidectomy vestibular approach: A case study and review of literature

BACKGROUND

Extrathyroid implantation or dissemination of thyroid tissue secondary to a thyroid procedure is rare. Most of these belonged to thyroid carcinoma with metastatic potential and uncommon for benign pathologies.

METHODS

We report the case of a 31-year-old female who was identified to have multiple subcutaneous implantation of thyroid tissue 5 years after transoral endoscopic thyroidectomy vestibular approach. A comprehensive literature search on implantation of thyroid tissue secondary to thyroid procedures was performed.

RESULTS

Accidental tearing of the capsule during previous surgery may lead to the subcutaneous implantation. Through literature review, a total 29 articles with 47 patients were identified. 33.3% were benign lesions, and implantation was mostly secondary to fine needle aspiration biopsy (46.5%).

CONCLUSIONS

Subcutaneous or port site implantation after endoscopic thyroid surgery may occur in benign thyroid pathologies and therefore, oncologic principles must be strictly followed during surgery regardless of its histopathological nature.

Needle tract seeding of papillary thyroid carcinoma after fine-needle capillary biopsy: A case report

BACKGROUND

Fine-needle biopsy is an accurate and cost-efficient tool for the assessment of thyroid nodules. It includes two primary methods: Fine-needle capillary biopsy (FNCB) and fine-needle aspiration biopsy. Needle tract seeding (NTS) is a rare complication of thyroid fine-needle biopsy mainly caused by fine-needle aspiration biopsy rather than FNCB. Here, we present an extremely rare case of a papillary thyroid carcinoma (PTC) patient with FNCB-derived NTS.

CASE SUMMARY

We report a 32-year-old woman with PTC who showed subcutaneous NTS 1 year after FNCB and thyroidectomy. NTS was diagnosed based on clinical manifestations, biochemistry indices, and imaging (computed tomography and ultrasound). Pathological identification of PTC metastases consistent with the puncture path is the gold standard for diagnosis. Surgical resection was the main method used to treat the disease. After surgery, thyroid function tests and ultrasound scans were performed every 3-6 mo. To date, no evidence of tumor recurrence has been observed.

CONCLUSION

FNCB is a safe procedure as NTS is rare, and can be easily removed surgically with no recurrence. Accordingly, NTS should not limit the usefulness of FNCB.