Concurrent spinal nerve root schwannoma and meningioma mimicking single‐component schwannoma

Abstract

We present a first case of concurrent tumors consisting of schwannoma and meningioma arising at the same spinal level in a patient without neurofibromatosis. A 49-year-old man without clinical evidence of neurofibromatosis presented with a 5-month history of right neck pain. MRI demonstrated an extradural tumor involving the right-sided C2 nerve root with a small intradural component. T1- and T2-weighted and contrast-enhanced MRI could not differentiate the intradural tumor as different from the extradural tumor. Total removal of the tumors was performed. No contiguity of the extradural tumor with the intradural tumor was seen. The intradural tumor attached strongly to the dura mater around the C2 nerve root exits. Intraoperative pathological diagnosis confirmed the extradural tumor as schwannoma and the intradural tumor as meningioma. We therefore thoroughly coagulated the dura mater adjacent to the intradural tumor and resected the dura mater around the nerve root exits together with the tumor. Pathological examination revealed that the resection edge of the extradural component consisted of a spinal nerve with thickened epineurium and was free of neoplastic cells. No schwannoma component was evident in the intradural tumor. No obvious transition thus existed between the extra- and intradural tumors. Distinguishing these tumors prior to surgery is critical for determining an optimal surgical plan, as schwannoma and meningioma require different surgical procedures. We therefore recommend a careful review of preoperative imaging with the possibility of concurrent tumors in mind.

Coexistence of neurofibroma and meningioma at exactly the same level of the cervical spine

“…9 Therefore, if an obvious tumor is already seen, as in our case, the meningioma can be easily missed and mimic a single-component tumor. 2 Nakamizo et al 2 presented a case of concurrent schwannoma and meningioma with a slight difference in signal intensity on magnetic resonance cisternography. In the current case, there was little difference in the signal intensity on contrast-enhanced MRI.…”

“…Two different tumors may grow independently at the same anatomical level of the spine without genetic predisposition. 2 It is also possible that the first tumor may alter its surrounding microenvironment, thereby facilitating the development of the second primary tumor. 2 The exact cause of the coexistence in the current case remains uncertain.…”

Concurrent Schwannoma and Meningioma Arising in the Same Spinal Level: A Report of Two Cases

“…Schwannomas and meningiomas are representative spinal tumors, comprising 30% and 25% of all spinal cord tumors, respectively. 3 – 5) Approximately, 75% of schwannomas arise in the intradural extramedullary region. A total of 15% of the lesions are found exclusively in the extradural area, and the rest have both intra- and extradural components.…”

“…Schwannomas are typically well-circumscribed tumors derived from the peripheral nerve. 3) Approximately 10–15% of schwannomas are dumbbell shaped. Schwannomas are usually depicted as iso- to hypo signal intensity on T1-weighted MR images and hyper- or mixed-signal intensity on T2-weighted MR images.…”

“…Schwannomas are usually depicted as iso- to hypo signal intensity on T1-weighted MR images and hyper- or mixed-signal intensity on T2-weighted MR images. 1 , 3 , 10) Meanwhile, in contrast-enhanced MR images (T1-CE), the tumor is well enhanced but often shows ring-like or irregular enhancement depending on the degenerative changes within the tumor. 1 , 10 – 12) By contrast, meningiomas tend to be small, single tumors and are typically found in the intradural extramedullary region.…”