The melanoma that grows on the toenail is toenail melanoma, which is very different from other types of melanoma and can bring great harm to the patients. The symptoms of toenail melanoma 1, tumor volume: smaller tumors have a better prognosis; the larger the volume, the worse the prognosis. The width of the contact area between the base of the tumor and the sclera is more important than the height of the tumor bulge. The wider the contact with the sclera, the more likely it is to spread outside the eye or to have systemic metastasis. 2, tumor cell type: spindle cell melanoma has a good prognosis, with a 5-year survival rate of 84%; mixed cell and necrotic melanoma has a poor prognosis, with a 5-year survival rate of about 50%; epithelioid cell melanoma has the worst prognosis, with a 5-year survival rate of less than 30%. 3. Extra-scleral spread: Choroidal or ciliary body melanoma has a poorer prognosis if it invades outside the sclera via the sclera or corneosclera. Such cases are prone to local recurrence or systemic metastasis and have a high mortality rate. 4. Tumor anterior margin location: When the anterior margin of the tumor is close to the ciliary body, the prognosis is worse. This may be because the ciliary body is rich in blood vessels and the movement of ciliary muscle may increase the chance of metastasis of tumor cells through blood vessels. In addition, because the tumor sites in the ciliary body and the peripheral part of the choroid are hidden and there are no obvious symptoms in the early stage, early diagnosis is difficult.