Leser–Trélat sign
（重定向自Leser Trelat sign）
The Leser-Trélat sign is the explosive onset of multiple seborrheic keratoses (many pigmented skin lesions), often with an inflammatory base. This can be an ominous sign of internal malignancy as part of a paraneoplastic syndrome. In addition to the development of new lesions, preexisting ones frequently increase in size and become symptomatic.