Types of phacomatosis pigmentovascularis associated with nevus cesius.

Phacomatosis pigmentovascularis (PPV) is a term encompassing a group of disorders characterized by the coexistence of segmental pigmented nevi of melanocytic origin and segmental capillary nevi. Several variants are characterized by a hallmark nevus cesius. Systematic reviews on the topic are lacking. An extensive review and critical reassessment of worldwide literature was carried out. A total of 435, 17, 19, and 17 cases of phacomatosis cesioflammea, phacomatosis cesiomarmorata, phacomatosis cesioflammeomarmorata, and phacomatosis melanocesioflammea, respectively, were identified. Specific clinical manifestations emerged for each variant. Postzygotic mosaic mutations affecting the GNAQ or GNA11 genes have been identified for all these entities. Four cases of nevus cesius associated with nevus anemicus (NA) were also retrieved. Phacomatosis cesioflammea is confirmed to be the most common PPV type by far. Its extracutaneous manifestations mostly consist of Sturge-Weber-Klippel-Trénaunay syndrome-like abnormalities, and ocular melanoma is a rare but relevant occurrence. The clinical associations of phacomatosis cesioflammeomarmorata mostly seem to result from the presence of cutis marmorata telangiectatica congenita. Phacomatosis cesioflammeomarmorata seems to resemble phacomatosis cesioflammea in several respects. A high frequency of NA and the Klippel-Trénaunay phenotype (or leg-length discrepancy) was observed in phacomatosis melanocesioflammea. The existence of "pseudodidymosis cesioanemica" is also corroborated.