Calcified spinal meningiomas: a systematic review of clinical characteristics, treatment strategies, and outcomes

Background: Calcified meningiomas involving the spine are rare but can pose significant surgical challenges. We systematically reviewed the literature on calcified spinal meningiomas. Methods: PubMed, EMBASE, Web-of-Science, and Scopus databases were searched to include studies reporting clinical data of patients with calcified spinal meningioma. Included articles were analyzed for symptoms, imaging, spine level of the tumor, tumor location relative to the spinal cord, calcification status, treatment regimen, recurrence, progression-free survival, and outcomes. Results: A total of 35 articles encompassing 94 patients were included. Most patients were female (90.4%), presenting with lower extremity weakness (44%) and/or lower extremity paresthesia (38.1%). Most calcified spinal meningiomas occurred in the thoracic spine (82%) and on the dorsal (33.3%) or ventral (27.2%) side relative to the spinal cord. Most tumors were intradural (87.2%). Histologically, most calcified spinal meningiomas were WHO grade I (97.4%) and psammomatous (50.7%). Most tumors demonstrated macroscopic calcification (48.9%). Most patients underwent gross total resection (91.5%) through a posterior approach (100%). Two patients (2.1%) received adjunctive radiotherapy. The most common treatment related complication was CSF leakage. Post-operatively, most patients demonstrated symptomatic improvement (75.5%) and 2 (2.1%) had local tumor recurrence. Conclusions: Calcified spinal meningiomas are uncommon but benign entities. These neoplasms tend to adhere to surrounding tissues and nerves and, thus, can be surgically challenging to remove. In most patients, safe gross total resection remains the standard of care, but accurate surgical planning is necessary to reduce the risks of postoperative complications.