Minimally invasive tubular removal of spinal schwannoma and neurofibroma - a case series of 49 patients and review of the literature

To evaluate the efficacy and safety of minimally invasive tubular removal of spinal schwannoma and neurofibroma. In this single-centre study, we retrospectively analysed 49 consecutive patients who underwent minimally invasive removal of a total of 51 benign spinal nerve sheath tumors using a non-expandable ( n = 18) or expandable tubular retractor ( n = 33) retractor system between June 2007 and December 2019. The extent of resection, surgical complications, neurological outcome, operative time, and estimated blood loss were recorded. Histopathology revealed 41 schwannomas and 10 neurofibromas. After a mean follow-up of 30.8 months, postoperative MRI showed gross total resection in 93.7%, and subtotal resection in 6.3% of the tumors. Three patients were lost to follow up. Of the subtotal resections, one was a schwannoma (2.4% subtotal resections in schwannomas) and two were neurofibromas (20.0% subtotal resections in neurofibromas). Intraspinal and paraspinal tumor localizations were equally accessible by minimally invasive tubular surgery. Conversion to open surgery was not required in any case. The mean operative time was 167 ± 68 min, and estimated blood loss was 138 ± 145 ml. We observed no major surgical complications. Spinal schwannoma and neurofibroma can be removed effectively and safely using a minimally invasive tubular approach, with satisfying extent of tumor resection comparable to the conventional open surgical technique and no increased risk for neurological deterioration.