cutaneous endometriosis cutaneous endometriosis cutaneous endometriosis is characterized by the appearance of papules at the umbilicus or in lower abdominal scars after gynecologic surgery in middle-aged women.: 628 the size averages to 2 cm in diameter. its colour ranges from blue to violet, brown or skin-coloured. rarely, endometriosis may present inside the muscles of the abdominal wall instead of the skin after caesarean section.