FCP begins as the sudden onset of numerous cutaneous papillomas that are clinically indistinguishable from viral warts.
[citation needed] The sudden eruption of papulonodules usually indistinguishable from common viral warts should suggest this diagnosis.
These papulonodules begin on the extremities, especially on the dorsa of the hands and the wrists and may disseminate to involve the entire body, including the face.
Malignant acanthosis nigricans may also become evident, many times with the sudden eruption of multiple seborrheic keratoses, known as the sign of Leser-Trélat.
[9][10][11] Florid cutaneous papillomatosis mandates a search for an underlying malignancy, recognizing that it may be seen in patients with multiple visceral carcinomas.
Histologic examination shows uniform and pronounced hyperkeratosis, acanthosis, and papillomatosis without epidermal vacuolization, parakeratosis, or eosinophilic inclusions suggestive of viral warts.
[12] The sudden quality of the eruption of florid cutaneous papillomatosis and its anatomic distribution should facilitate distinction from widespread common warts and from epidermodysplasia verruciformis.