Phacomatosis cesioflammea is characterized by the co-existence of a large nevus cesius (i.e., aberrant Mongolian spot, or nevus fuscocoeruleus) and an extensive nevus flammeus (i.e., port-wine stain). This sporadic genetic skin disorder represents a particular type of phacomatosis pigmentovascularis, a group of disorders that may reflect twin spotting. We report on a 28-year-old woman with aberrant Mongolian spots, bilateral melanosis bulbi, and systematized nevus flammeus partly intermingled with nevus anemicus. Moreover, pronounced lipohypoplasia of the right buttock and thigh as well as hypoplasia of the right breast are present. This anomaly of fatty tissue has not previously been reported in phacomatosis cesioflammea and further expands the clinical spectrum of this mosaic disorder. The patchy distribution of lipohypoplasia and its spatial relationship with vascular lesions strongly support the hypothesis of a postzygotic recombination event.