Cutaneous meningiomas—a clinicopathologic study

Twenty‐five cases of cutaneous meningioma and related processes were reviewed. Three types of meningioma cutis were noted. Type I occurs in the scalp, face, or paravertebral region of children and young adults, is usually present at birth, and generally has a benign course. This primary cutaneous meningioma bears similarities to developmental defects and probably originates from arachnoid cell rests displaced during embryogenesis into the cutis or subcutis. Type II occurs around sensory organs of the head and along the course of cranial and spinal nerves. It generally appears in adults as a de novo lesion and represents a cutaneous extension from an ectopic soft tissue meningioma, probably arising from arachnoid cell rests displaced along nerve sheaths. Type III represents an extension into the skin from a central nervous system meningioma infiltrating across bone or a bone defect. Prognosis for Types II and III is less favorable than for Type I. Clinically, cutaneous meningiomas resemble a variety of common skin lesions. The histopathologic appearance is usually but not always characteristic.