Eccrine spiradenoma is a rare, benign, adnexal skin tumor of the sweat gland, which may manifest in any part of the body. It is typically located in the dermal or the subcutaneous fat layer. Eccrine spiradenomas rarely progress to malignant transformation and only a few cases of malignant transformation have been reported. Due to its rarity, there have been few reports about the sonographic appearances of eccrine spiradenoma. We report the sonographic findings in one case of eccrine spiradenoma, located in the subcutaneous fat and the deep dermal layers of the upper arm in a middle-aged woman.

Proliferating trichilemmal tumor (PTT) is a rare tumor that originates from the outer root sheath of a hair follicle. About 90% of PTTs occur on the scalp. The sonographic findings of PTT in the subungual region have not been reported previously. In our case, sonography showed a heterogeneous mass containing echogenic foci with no detectable intratumoral vascularity. These echogenic foci probably represent keratin and cholesterol. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:215-217, 2018.

Metastasis to the thyroid is very rare in hepatocellular carcinoma (HCC) and only a few cases have been reported. Herein, we report a rare case of metastatic HCC to the thyroid in a 63‐year‐old man and discuss the various radiologic findings. Computed tomography (CT) revealed a heterogeneous enhancing mass that had invaded the thyroid cartilage in the left upper thyroid, compressing the airway. Ultrasonography (US) showed a heterogeneous hypoechoic mass with increased vascularity in the peripheral portion. The mass showed focal intense uptake on positron emission tomography‐computed tomography (PET‐CT). The patient underwent US‐guided core needle biopsy and the final diagnosis was metastatic HCC.