Papillary Thyroid Cancer Presenting with Incidental Skin Lesion: Critical Management of Distant Metastasis

Papillary thyroid cancer can usually metastasize to neck lymph nodes. Distant metastases are generally seen as solid organ metastases, in contrast, skin metastasis can rarely be seen. We present a case with papillary thyroid cancer diagnosed with skin metastasis as first clinical sign of distant organ metastasis. A 63-year-old male patient admitted with a skin lesion in the left lateral neck. He had undergone subtotal thyroidectomy 14 years ago without relevant history of malignancy. Follicular variant papillary thyroid cancer was detected in the excisional biopsy performed from the cutaneous lesion. A 12 × 10 × 8 mm hyperechoic nodule in the left lobe was detected in USG and evaluated as Bethesta-III in fine needle aspiration biopsy. Bilateral multiple lung metastases were detected on thorax CT, trucut-biopsied from largest nodule and confirmed as metastasis. Carcinoma was not detected in total thyroidectomy, and post-operative multiple RAI therapies were applied. Patients without history of thyroid cancer rarely present with skin metastases and thyroid cancer should not be overlooked in differential diagnosis. Despite meticulous evaluation of the thyroidectomy specimen, tumor may not be detected in the gland. Skin metastasis in papillary thyroid cancer should be evaluated as distant metastasis and investigations for other metastases should be done, and the treatment should be planned in a multidisciplinary manner.