P059: A case of primary cutaneous endometriosis on umbilicus

Primary cutaneous endometriosis of umbilicus, which is also called Villar’s nodule is a rare manifestation of endometriosis, representing 0.5% to 1% of all patients with ectopic endometriosis. Ectopic endometriosis could be found in nearly every tissue and it mostly occurs at surgical scar tissue secondarily to abdominal surgical procedures. We report a case of a 43-year-old nulligravida female presented with 2.0x2.0 cm sized brownish to purplish colored rough surfaced nodule on the umbilicus since several years ago. Histopathological examination revealed dilated glandular structures surrounded by cellular endometrial-type stroma and deep perivascular lymphocytic infiltration. According to these findings, the umbilical lesion was diagnosed as primary cutaneous endometriosis. A surgical local excision was done and medical treatment with Dienogest(progestin medication) is ongoing until now without recurrence. Herein, this case suggests that dermatologists should consider primary cutaneous endometriosis when a nodule on umbilicus is clinically similar to a keloid, and prior to initiation of treatment, histologic confirmation should be prioritized.