Streaks are brownish-black linear structures of variable thickness that are found in benign and malignant lesions. They are typically found at the periphery of a lesion and are not necessarily connected to the lines of the pigment network. They are sometimes seen throughout the lesion. In the past these linear structures were referred to by several different terms including radial streaming and pseudopods. Streaks are formed by heavily pigmented, confluent junctional nests of melanocytes that extend through the epidermis and bridging nests of melanocytic cells within the epidermis and papillary dermis. Streaks at the periphery of a lesion are characteristic of superficial spreading melanoma. A symmetric, radial arrangement over an entire lesion is seen in spindle cell nevus.