Segmental Congenital Vascular Anomaly With Atrophy, Ulceration and Scarring With Complications in Pregnancy.

A 33-year-old woman with a segmental non-involuting congenital vascular anomaly of the left neck developed pain and ulceration in pregnancy and left-sided Horner's syndrome after delivery. Mutational analysis of affected tissue showed a missense mutation in GNA11 (Glu209) and a second mutation in PIK3CA. Sirolimus therapy resulted in healing of the ulceration and resolution of the Horner's syndrome.