What are the light-brown colored spots on a newborn's trunk and back referred to?

The light-brown colored spots on a newborn's trunk and back are referred to as café au lait spots. These hyperpigmented lesions can be present at birth or develop during infancy. They are typically oval or irregular in shape and can vary in size. The presence of these spots without other associated clinical signs is considered normal, but it is important for healthcare providers to monitor the number and size, as multiple café au lait spots can be associated with certain genetic conditions, such as neurofibromatosis.

In contrast, nevus simplex, commonly known as "stork bites," are flat, pink marks that often appear on the back of the neck or eyelids but do not have the same light-brown coloration. Mongolian spots are bluish-gray macules usually found on the lower back and buttocks of infants, especially those with darker skin tones, and are different in color and location. Cherry angiomas are small, bright red spots that typically appear in older children or adults, not newborns, and they are vascular lesions rather than pigmented spots.