There are white patches underneath the breasts, considering that it may be vitiligo, post-inflammatory depigmentation or anemic nevus, and so on. 1. Vitiligo: Vitiligo is a disease of white patches on the skin caused by the destruction of melanocytes, which is usually manifested as one or several white patches of varying sizes. The center of the patch is usually white and prominent, and the skin around it is pale white patches. They can be round, oval or irregular. 2. Post-inflammatory depigmentation: Generally speaking, due to acute and chronic eczema, dermatophytosis, etc., transient depigmentation of the skin will appear during the recovery period, which can be improved by itself after a period of time. 3. Anemic nevus: it is a congenital pigment loss disease and can be found soon after birth. The skin of the affected area is not red when rubbed hard. White patches underneath the nipple may also be caused by other diseases, such as anaplastic nevus, etc. It is recommended that you consult a doctor in time to find out the cause and treat it accordingly.