Most ovarian teratomas are a type of benign tumor on the ovaries, but a few may become malignant. Therefore, if an ultrasound suggests an ovarian teratoma and it is relatively small, around two to three centimeters, without any symptoms, we can temporarily observe it. However, the condition is that we should test for tumor markers, such as checking if there are significant increases in CA-125 or AFP, to see if there's a tendency for malignancy. Another condition is that regular follow-up examinations are essential. If there's a sudden increase in size in a short period or a continuous growth, it is advisable to consider surgical treatment, as early surgical intervention tends to have better outcomes.