RESUMEN
BACKGROUND: Congenital midline spinal hamartoma is a very rare tumor-like proliferation that mostly occurs during childhood. It consists of mature, well-differentiated ectodermal and mesodermal elements that present in an abnormal location and are mostly associated with neurofibromatosis type 1 and spinal dysraphism. CASE DESCRIPTION: A 5-month-old male patient presented with complaint of a bump over the lower back. The bump was already present since birth with the size of approximately 3 cm in diameter and slow growth. There were no other associated symptoms besides the bump on the lower back. In the physical examination, we found a subcutaneous mass with associated skin dimple located on the midline of the lower back. Computed tomography scan of the spine showed a mass that arose from inside the dura and a closed spinal dysraphism from L3 vertebra to the sacrum. A subtotal resection was performed, and the histopathology feature showed fat cells, cartilage, skeletal muscle fibers, nerve, and blood vessel. After 6 months follow-up, no symptoms or neurologic deficit were present, and no further growth was shown on the latest computed tomography scan. CONCLUSIONS: Congenital midline spinal hamartoma is very rare and seldom addressed. Most patients present with a cosmetic defect and rarely with associated symptoms. Tissue biopsy is still the best modality to definitively diagnose hamartoma and to exclude other diagnoses. Surgical excision of the tumor is still the mainstay treatment, especially for patients who are not neurologically intact and to correct the cosmetic skin defect.
