Neurolymphomatosis in the Cauda Equina Diagnosed by an Open Biopsy

Non-Hodgkin Lymphoma of Cauda Equina: A Diagnostic Conundrum: Case Report

Primary central nervous system lymphoma (PCNSL) is uncommon with scarce cases having involvement of the spinal cord. Cauda equina is unique in its location and shows very rare involvement by diseases pathologies. When the same occur, they pose a lot of diagnostic difficulties as the location is difficult to access with overlapping radiologic abnormalities. It is an unusual location for lymphomas to occur with only few cases reported in literature. The cauda equina lymphomas may mimic other entities which occur at that site. Histopathology is the gold standard for the same. Here, we report an unusual case of cauda equina lymphoma mimicking a myxopapillary ependymoma in a 50-year-old male.

[A case of primary central nervous system lymphoma with marked cauda equina enlargement]

An 80-year-old woman presented with subacute right lower limb pain and bilateral lower limb weakness. MRI of the spine showed marked cauda equina enlargement with contrast enhancement. Cerebrospinal fluid (CSF) examination showed elevated cell count, decreased glucose, and elevated protein. Cytology of the CSF showed class V, which together with B-cell clonality by flow cytometry, led to the diagnosis of primary central nervous system lymphoma (PCNSL). The patient was treated with steroid, radiation, and chemotherapy. Despite the reduction in lesion size, her neurological symptoms revealed no improvement. PCNSL with cauda equina lesions are rare and often require highly invasive cauda equina biopsy for diagnosis. In recent years, some studies reported useful CSF biomarkers, but they may have some problems. Therefore, as in this case, the combination of cytology, flow cytometry and, CSF biomarkers could be a substitute method for invasive biopsies, and contribute to the early treatment of PCNSL.

Perineural spread of peripheral neurolymphomatosis to the cauda equina

OBJECTIVE

Neurolymphomatosis (NL) is a rare manifestation of lymphoma confined to the peripheral nervous system that is poorly understood. It can be found in the cauda equina, but extraspinal disease can be underappreciated. The authors describe how extraspinal NL progresses to the cauda equina by perineural spread and the implications of this on timely and safe diagnostic options.

METHODS

The authors used the Mayo Clinic medical records database to find cases of cauda equina NL with sufficient imaging to characterize the lumbosacral plexus diagnosed from tissue biopsy. Demographics (sex, age), clinical data (initial symptoms, cerebrospinal fluid, evidence of CNS involvement, biopsy location, primary or secondary disease), and imaging findings were reviewed.

RESULTS

Ten patients met inclusion and exclusion criteria, and only 2 of 10 patients presented with cauda equina symptoms at the time of biopsy, with 1 patient undergoing a cauda equina biopsy. Eight patients were diagnosed with diffuse large B-cell lymphoma, 1 with low-grade B-cell lymphoma, and 1 with mantle cell lymphoma. Isolated spinal nerve involvement was identified in 5 of 10 cases, providing compelling evidence regarding the pathophysiology of NL. The conus medullaris was not radiologically involved in any case. Lumbosacral plexus MRI was able to identify extraspinal disease and offered diagnostically useful biopsy targets. FDG PET/CT was relatively insensitive for detecting disease in the cauda equina but was helpful in identifying extraspinal NL.

CONCLUSIONS

The authors propose that perineural spread of extraspinal NL to infiltrate the cauda equina occurs in two phases. 1) There is proximal and distal spread along a peripheral nerve, with eventual spread to anatomically connected nerves via junction and branch points. 2) The tumor cells enter the spinal canal through corresponding neural foramina and propagate along the spinal nerves composing the cauda equina. To diffusely infiltrate the cauda equina, a third phase occurs in which tumor cells can spread circumdurally to the opposite side of the spinal canal and enter contralateral nerve roots extending proximally and distally. This spread of disease can lead to diffuse bilateral spinal nerve disease without diffuse leptomeningeal spread. Recognition of this phasic mechanism can lead to identification of safer extraspinal biopsy targets that could allow for greater functional recovery after appropriate treatment.

Primary Extranodal NK/T-Cell Lymphoma Presenting as Neurolymphomatosis Involving Multiple Cranial Nerves: A Case Report

Neurolymphomatosis (NL) is a rare condition caused by the lymphomatous or leukemic infiltration of nerves and manifests as neuropathy. Most often, NL is associated with B-lineage non-Hodgkin lymphoma (NHL) and only infrequently occurs in conjunction with T- or NK-lineage NHL. Extranodal NK/T-cell lymphoma (ENKTL)-associated NL is exceedingly unusual, with only 9 cases described in the English language literature, in addition to our case. Diagnosis of NL is challenging, as the entity can mimic neuropathies of more common etiologies, and an adequate biopsy may be difficult to obtain. Timely diagnosis demands a high index of suspicion, especially for patients without a history of hematologic malignancy. We expand upon a unique case of NL exclusively involving cranial nerves and cauda equina nerve roots, as the initial manifestation of ENKTL, and contextualize our findings within the framework of previously reported NK/T-lineage NL cases.

Primary Cauda Equina Lymphoma Treated with CNS-Centric Approach: A Case Report and Literature Review

Primary cauda equina lymphoma is an extremely rare entity previously documented in only 24 reported cases. Primary cauda equina lymphoma represents a subtype of neurolymphomatosis, which occurs when lymphoma cells with neurotropism infiltrate and destroy peripheral nerves, spinal nerve roots, nerve plexuses and cranial nerves. The cauda equina is an anatomic structure located in the lower part of the spinal canal consisting of multiple lumbar and sacral nerve roots. Herein, we report a unique case of primary cauda equina diffuse large B-cell lymphoma presenting as a tumor mass in the lower spinal canal, which was treated with a CNS-centric treatment approach followed by autologous hematopoietic stem cell transplantation.

Disorders of the Cauda Equina

PURPOSE OF REVIEW

Cauda equina dysfunction (often referred to as cauda equina syndrome) is caused by a diverse group of disorders that affect the lumbosacral nerve roots. It is important to recognize dysfunction of the cauda equina quickly to minimize diagnostic delay and lasting neurologic symptoms. This article describes cauda equina anatomy and the clinical features, differential diagnosis, and management of cauda equina disorders.

RECENT FINDINGS

The diagnosis of disorders of the cauda equina continues to be a challenge. If a compressive etiology is seen, urgent neurosurgical intervention is recommended. However, many people with clinical features of cauda equina dysfunction will have negative diagnostic studies. If the MRI is negative, it is important to understand the diagnostic evaluation and differential diagnosis so that less common etiologies are not missed.

SUMMARY

Cauda equina dysfunction most often occurs due to lumbosacral disk herniation. Nondiskogenic causes include vascular, infectious, inflammatory, traumatic, and neoplastic etiologies. Urgent evaluation and surgical intervention are recommended in most cases of compressive cauda equina syndrome. Other types of treatment may also be indicated depending on the etiology.

Primary Central Nervous System Lymphoma with Peripheral Nerve Involvement: Case Report

A 50-year-old man presented with dizziness and hearing disturbance in the right ear. Magnetic resonance imaging (MRI) revealed a well-enhanced mass lesion in the right cerebellopontine (CP) angle that appeared to originate in the cerebellum. A surgical specimen obtained at the subtotal resection with craniotomy revealed a diffuse large B-cell lymphoma (DLBCL). During the three courses of chemotherapy with high-dose methotrexate (MTX) with leucovorin rescue, he developed a right abducens palsy, left oculomotor palsy, left facial palsy, right trigeminal sensory disturbance, and paraparesis. Although the brain MRI showed that the CP angle tumor had disappeared completely following chemotherapy, enhanced lesions along the cauda equina were detected on a lumbar spine MRI. FDG-PET (18 F-fluorodeoxyglucose positron emission tomography) revealed multiple high-uptake abnormalities in the cranial nerves and spinal nerves. Tumor cells were found in the cerebrospinal fluid specimen from a lumbar puncture. Craniospinal irradiation was performed, including all the abnormal FDG high-uptake areas, and was effective in relieving the patient's symptoms. On FDG-PET, the high-uptake abnormalities in the peripheral nerves disappeared. However, five weeks after the irradiation, he developed right trigeminal sensory disturbance, hoarseness, dysphagia, and right arm pain. FDG-PET disclosed multiple high-uptake abnormalities in more peripheral portions of the cranial nerves and spinal nerves. Chemotherapy with rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine (Oncovin®), and prednisolone (R-CHOP) was then resorted to which mitigated his symptoms. On follow-up FDG-PET, the high-uptake abnormalities in the peripheral nerves disappeared again.