CT findings of pleomorphic hyalinizing angiectatic tumor (PHAT) of soft parts of the neck

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a rare and recently recognized mesenchymal tumor with intermediate malignant potential, most of which arises in the soft tissue of the extremities with obvious specificity on histopathology. Here, we report a case of CT findings of PHAT arising from the posterior neck as a 3.4 × 4 × 5-cm mass in a 35-year-old woman. Precontrast CT showed an ill-defined, inhomogenous and oval-shaped mass. On contrast-enhanced CT, the mass appeared well defined except for a very small part, most of which showed marked and heterogenous enhancement, with a maximum CT value of 161 HU, which was almost identical to that of the vessels.