TABLE 1

Differential diagnosis of a firm, hyperpigmented, macular skin lesion

ConditionCharacteristics
Lentigo malignaIrregular asymmetric pigmented macules that grow centrifugally
Dermatofibrosarcoma protuberansSimilar to dermatofibroma, but larger, irregular border, deeper skin invasion
Seborrheic keratosisShiny (“oily”), well-demarcated macule or papule, “stuck-on” appearance
Epidermoid inclusion cystFlat or raised flesh-colored cystic lesion; often has dark central punctum; size varies; may spontaneously drain
DermatofibromaSlow-growing, firm, tan to reddish-brown papules, < 1 cm, that “dimple” to lateral compression