Final answer:
Leukoplakia is a precancerous lesion that manifests as white patches in the mouth. When a patient presents with leukoplakia, the nurse practitioner must rule out oral cancer as a possibility.
Step-by-step explanation:
Leukoplakia is a condition characterized by white patches or plaques that develop on the mucous membranes of the mouth. It is considered a precancerous lesion and can increase the risk of developing oral cancer. Therefore, when a patient presents with leukoplakia, the nurse practitioner must rule out oral cancer as a possibility. Other conditions such as esophageal cancer, aphthous ulcers, and oral thrush may also cause white lesions in the mouth, but oral cancer is the most concerning and must be ruled out first.