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BACKGROUND Differences in presentation and outcomes in children and adults with spinal dermoid tumors have not been documented. Surgical outcomes for dermoid tumors in different spinal cord planes have also not been studied. METHODS Retrospective review of 59 consecutive patients who underwent surgery for intraspinal dermoid tumors at a single institution. Tumors were categorized as purely extramedullary (n=15), purely intramedullary (n=28) or intramedullary-extramedullary (n=16) based on intraoperative and imaging findings. RESULTS The cohort was comprised of 45 children and 14 adults. The presence of a dermal sinus and prior history of meningitis was significantly associated with childhood presentation (p = 0.001 and p = 0.013, respectively). Most adults had purely intramedullary tumors (n=12, 85.7%) as compared to children (35.6%, p=0.001). Gross total resection (GTR) was achieved in 33.3% and 41.7% of children and adults, respectively (p=1.000). Factors associated with GTR on logistic regression analysis included short segment (≤3 levels) dermoid cysts (p=0.037) and absence of an intramedullary component (p=0.027). Forty-seven patients were followed up over a mean period of 72.9±8.3 months. Preoperative motor deficits were more likely to improve in children than in adults (p=0.005). Recurrences were seen in 14.9% of cases (all with intramedullary tumors) at a median interval of 58 months (range 40-166 months) after surgery, with no differences in recurrence-free survival between children and adults (p=0.936). CONCLUSION Presentation of dermoid cysts is distinctively different in children and adults. GTR is a challenge for intramedullary and large tumors. Recurrences may manifest several years after surgery mandating life-long surveillance.