gms | German Medical Science

Objective: Intramedullary tumors are exceedingly rare, accounting for only 2-4% of all CNS neoplasms. The majority is graded as benign tumors, however surgical treatment is difficult with up to 30% aggravation of neurological impairment. We analyzed a consecutive series of patients presenting with intramedullary tumors, which were treated in our department. We especially focused on the extent of resection, functional outcome and the frequency of recurrence.

Method: We investigated 53 patients (23 female, 30 male) receiving microsurgical resection for intramedullary spinal tumors in our department between 2003 and 2011. The mean age was 46.3 years (range: 0.9 - 82.7 years); maximal diameter, edema, intratumoral hemorrhage and cranio-caudal extension of the tumor was determined based on the preoperative MRI. Tumor consistency, midline detection, piece meal or en bloc resection as well as the EOR was extracted from the surgery reports. Outcome was measured by the Karnofsky (KPI), the McCormick (MCS) and the Medical Research Coucil Neurological Performance (MRC-NPS) score. In addition, paresis grade (0-5), and the extent of sensory deficits, spasticity, bladder dysfunction ataxia and pain was recorded.

Results: The most frequent histological diagnosis was ependymoma followed by astrocytoma and hemangioblastoma. The majority of tumors corresponded to WHO grade II (32.1%), the mean MIB-labeling index was 14.1%. The surgical mortality and morbidity was 0% and 7.6% respectively. Gross total resection (GTR) was accomplished in 73.6% of all cases, with ependymal histology showing the best results (p<0.01). Tumor recurrence was observed in 11.3%, with a significant correlation in uni- and multivariate analysis between age, histology, grading and MIB-1 labeling and recurrence. The KPI remained stable, however both MCS and MRC-NPS improved significantly at follow-up after being stable immediately after surgery (p<0.001). At follow-up, pain and sensory deficits showed the best results with improvement in 67.9% and 64.2% and worsening in only 5.7% and 11.3%, respectively. In contrast, paresis and bladder dysfunction improved only in 13.2% and 20.8% and worsened in 17.0% and 13.2%, respectively. Interestingly, GTR specifically improved both MCS and bladder dysfunction.

Conclusions: Microsurgical resection improves preferentially and significantly pain and sensory deficits, whereas paresis and vegetative function show significantly worse results.