8743/3 Superficial spreading melanoma


ICD-O-3 topography code: C44
ICD10: C43

Superficial spreading melanoma (SSM) is a subtype of malignant melanoma that grows laterally before vertical invasion develops. During the radial growth phase, large neoplastic melanocytes spread among keratinocytes in a ?buckshot? or pagetoid pattern throughout the epidermis, resulting in irregularly pigmented macules of often considerable diameter. With the onset of invasion, the lesions develop into slightly raised plaques with asymmetric outlines. These plaques often become erosive, ulcerated and crusted and tend to bleed. SSM typically develops on skin with acute intermittent sun exposure. The most frequently affected sites are legs (women) and trunk (men).
Superficial spreading melanoma is the most frequent subtype of melanoma, accounting for almost two thirds of all melanomas in fair-skinned people. The prognosis is relatively favourable1
LeBoit PE, Burg G, Weedon D, Sarasin A (Eds.)
World Health Organization Classification of Tumours. Pathology and Genetics of Skin Tumours
3rd Edition
IARC Press: Lyon 2005