A lichenoid keratosis is an inflamed seborrheic keratosis that presents as a pink shiny papule or plaque with an appearance that resembles that of a nodular or cystic basal cell cancer.
Dermatosis papulosa nigra is a term given to the papular seborrheic keratoses (most often seen as dark brown 1-3 mm papules) on the face of individuals with darker skin colors.
Relatively rapid onset of numerous SKs may be a cutaneous sign of internal malignancy. Multiple eruptive SKs in association with a visceral cancer is referred to as the sign of Leser-Trélat. The most common associated malignancy is adenocarcinoma of the gastrointestinal tract.
L82.1 – Other seborrheic keratosis
25499005 – Seborrheic keratosis
Differential Diagnosis & Pitfalls
- Melanoma – For any dark or atypical appearing pigmented lesion, the diagnosis of melanoma should be ruled out.
- Pigmented basal cell carcinoma
- Melanocytic nevus
- Bowen disease
- Bowenoid papulosis
- Stucco keratosis
- Cutaneous horn
- Nevus sebaceus
- Epidermodysplasia verruciformis
- Fibroepithelioma of Pinkus
- Acrokeratosis verruciformis of Hopf
- Arsenical keratosis
Drug Reaction Data