Is the white mark- a depigmented mark- like Vitiligo ?? I would need photos for confirmation. Vitiligo is an autoimmune disorder. It may have exacerbations/ improvements depending on various factors. This is a treatable condition, however, cure may not be promised. That is – the pigmentation may be attempted to be improved to normal with the help of medications. If the disease is active, you’ll need immunosuppressive medication to control its spread. Also phototherapy is a good form of therapy to improve your condition. Kindly see a qualified dermatologist near you. Warm regards