Subungual melanoma, clinically, displays different symptoms depending on the stage. In its early stages, subungual melanoma primarily manifests as changes in nail color, with some cases showing localized thickening of the nail. As the melanoma progresses, abnormal secretions such as bloody or serous fluids may appear under the nail, and the nail itself may become uneven. As the subungual melanoma invades surrounding tissues, symptoms such as swelling, pain, or bleeding in the localized fingernail may occur. In advanced stages, symptoms of metastatic sites, such as coughing, chest pain, and chest tightness from lung metastases, can also manifest.