History:

Sign of Leser-Trelat, or eruptive seborrheic keratosis, is defined as the association of the abrupt appearance of multiple seborrheic keratoses, often pruritic, with an underlying internal malignancy. This sign has been regarded as a rare but reliable cutaneous marker of internal malignancy. The pathogenesis of the sign of Leser-Trelat is still unknown. The sign is not widely accepted as a paraneoplastic syndrome because seborrheic keratoses and cancer are common findings in the elderly.