Laser-Trélat sign improved after the resection of a tiny ground-grass nodule: a case report.

The Laser-Trelat sign refers to eruptive seborrheic keratoses accompanied by internal malignancies, mainly abdominal advanced ones. Detailed associations remain unclear, and the skin lesions do not improve with the treatment of internal malignancies in half of the patients. Herein, we report a rare case of Laser-Trelat sign that improved after resection of a 0.6-cm pulmonary ground-glass nodule: adenocarcinoma in situ. The patient requested the resection with the hopes of improving the skin lesions, though immediate resection was not indicated oncologically. With informed consent, despite possible failure in improving cutaneous diseases, thoracoscopic partial resection of the right lower lobe was performed. Fortunately, her seborrheic keratoses substantially improved after the resection, without exacerbation. To our knowledge, this is the first report describing such a clinical course. It is essential to inform patients regarding the indication of treatment for internal malignancy and its limitation in improving eruptive seborrheic keratoses.