Spinal teratoma with renal differentiation--a rare phenomenon: report of two patients.

The occurrence of intradural spinal teratomas in association with spinal dysraphism is uncommon and even rarer is renal differentiation in a teratoma. We report two rare cases of patients with spinal dysraphism, split cord malformation and intraspinal teratomas with renal differentiation in a boy of 1 year and a girl of 3 years of age. Surgical excision of the mass, detethering of the cord and repair of the lipomyelomeningocele was done. Pathologic examination in both the cases revealed features of a mature teratoma with nephrogenic differentiation in the form of elements of mature renal tissue. To the best of our knowledge, spinal teratoma with renal component has not been described previously.