Cutaneous metastasis as the presenting sign of papillary thyroid carcinoma

Radiofrequency ablation of recurrent thyroid cancers: anatomy-based management

Although differentiated thyroid cancer has an excellent prognosis and low mortality, its recurrence rate has been reported to be very high. While surgery is recommended as the standard treatment for recurrent thyroid cancer, reoperation may increase the incidence of complications due to fibrosis and anatomical distortion. In patients with high surgical risk or those who refuse repeated surgery, ultrasonography-guided ablation techniques including radiofrequency ablation, ethanol ablation, and laser ablation are suggested as alternative treatments. In this manuscript, we introduce an anatomy-based management concept for radiofrequency ablation for recurrent thyroid cancer, and present a review of the relevant literature, including indications, basic techniques, clinical outcomes, and complications.

Cutaneous metastases: A great imitator

Neoplastic cells originating from a primary cancer can uncommonly spread to the skin, where they suggest a poor prognosis for the patient. In women, melanoma, breast, ovarian, oral cavity, and lung are the most common primary sources; in men, melanoma, lung, colon, and squamous cell carcinoma of the head and neck predominate. The classic presentation of cutaneous metastases is a firm, painless, flesh-colored to an erythematous dermal nodule (or nodules); however, several other presentations, including inflammatory, cicatricial, and bullous lesions, have been reported. Cutaneous metastases may also mimic benign conditions such as lipomas, hemangiomas, or cellulitis. A high degree of clinical suspicion is necessary, and the diagnosis is confirmed by biopsy, which may also be used to establish the primary malignancy if unknown, as the histopathologic appearance of the metastatic tissue may mimic the primary tumor. Treatments include excision of the metastases, chemotherapy, immunotherapy, radiation, and/or palliative care.

An H-TERT Mutated Skin Metastasis as First Occurrence in a Case of Follicular Thyroid Carcinoma

Differentiated thyroid cancer arising from thyroid follicular epithelial cells is the most frequent endocrine malignancy, and skin metastases are very rare. We describe a case of a 70-year-old women with a history of an indeterminate thyroid nodule on cytology. A painless, erythematous skin nodule of about 7 mm diameter was removed from the scalp and diagnosed as a metastasis from thyroid cancer. After total thyroidectomy, a histological diagnosis of follicular thyroid cancer was made. Two cycles of radioactive iodine were performed. Both the follicular thyroid carcinoma (FTC) and the metastasis were investigated for the presence of BRAF/RAS and TERT promoter mutations. The results showed that the cutaneous metastasis was BRAF wild-type and TERT promoter-mutated (position g.1,295,228 C>T); in contrast, the primary thyroid lesion was negative for both molecular markers.

Concurrent metastases of papillary thyroid carcinoma to the scalp and Meckel's cave

We present the case of a 65-year-old man with severe headaches and unilateral facial weakness, seen in consultation by the dermatology service to rule out primary cutaneous melanoma after brain imaging identified an enlarging mass within the right trigeminal (Meckel's) cave. Examination revealed only a pair of erythematous papules on the scalp, for which biopsy demonstrated metastatic papillary thyroid carcinoma. Further evaluation and subsequent thyroidectomy confirmed the origin of widespread internal disease, followed by definitive excision of scalp lesions and multimodal management of systemic involvement. Whereas presentation of metastasis to the skin is highly variable, a low threshold for biopsy may allow for histological identification of internal disease not otherwise considered in the clinical differential.

Solitary skin metastasis of papillary thyroid carcinoma

A solitary skin metastasis is a rare manifestation of papillary thyroid carcinoma (PTC). A 55-year-old woman presented with a movable subcutaneous nodule in her anterior neck for several months. Three years ago, she underwent total thyroidectomy and remnant ablation for classical PTC (pT3N0M0) and was under thyroxine suppression therapy without any evidence of recurrent disease. The subcutaneous nodule was 0.4 cm in size, firm, and movable without any change in the overlying skin. Recurrent PTC was confirmed after excision biopsy. Eight months after, she got a new nodule along the previous excision site. After punch biopsy, metastatic PTC was confirmed in the deep dermis and was re-excised with a clear resection margin. This is the first report of a case of solitary skin metastasis of PTC in Korea. Although solitary skin metastasis of PTC is rare, it should be considered in patients with a skin nodule.