Neoplastic Cauda Equina Syndrome: When Do We Not Operate?

Abstract

BACKGROUND AND IMPORTANCE:

Burkitt lymphoma is a high-grade non-Hodgkin lymphoma that can cause spinal cord compression leading to neurological compromise. Prompt interventions are critical to prevent permanent deficits. Through this case report, we highlight the rapid resolution of acute cauda equina syndrome in an adolescent with Burkitt lymphoma in the setting of tandem spinal cord and cauda equina compression.

CLINICAL PRESENTATION:

An 18-year-old man developed cervical lymphadenopathy and weight loss 2 months prior and was diagnosed with Burkitt lymphoma 1 month earlier. He developed bilateral lower extremity paresthesias 1 week before presentation, with acute worsening over 24 hours resulting in weakness and urinary overflow incontinence. MRI revealed epidural masses at T5 to T7 causing spinal cord compression and L5/S1, causing severe cauda equina compression. He had left foot weakness, saddle anesthesia, poor rectal tone, and urinary retention, draining more than 1000 mL of urine after Foley catheter insertion. The radiosensitivity of Burkitt lymphoma prompted emergent radiotherapy (800 cGy) within 14 hours of presentation. On postradiation day 1, left foot strength improved, and by day 3, full neurological function, including bladder control, was restored. Repeat MRI on postradiation day 4 showed complete resolution of both epidural masses. He was discharged neurologically intact, requiring no surgical intervention, and continued chemotherapy as planned.

CONCLUSION:

This case underscores the critical need for the spine surgeon to understand the histology and radiosensitivity of any spinal neoplastic processes. For radiosensitive tumors such as lymphoma, emergent radiation can lead to rapid resolution of neurological deficits without requiring surgery.

ABBREVIATION:

BED

biologically effective dose.

Burkitt lymphoma is a non-Hodgkin lymphoma characterized by MYC gene translocation and deregulation on chromosome-8. It is more prevalent in children, with annual incidence of 3 to 6 per 100 000 population.¹ Central nervous system and spinal column involvement (2%-7%)² may lead to significant neurological deficits.^3,4

Early intervention is crucial for spinal cord or cauda equina compression to minimize neurological damage. Although surgery is often undertaken for acute neurological decline, radiation can be equally effective for radiosensitive tumors, such as lymphoma.^5,6 Although multiple surgical options exist for management of metastatic spine disease—decompression, separation surgery, en bloc resection, and stabilization alone—as informed by Neurologic, Oncologic, Mechanical, and Systemic Disease and Spinal Instability Neoplastic criteria,^7-9 surgery is inherently morbid.¹⁰ Spine surgeons must therefore be well-versed in tumor biology and radiation sensitivity.^11-13

Through this SCARE-adherent case report,¹⁴ we highlight rapid resolution of acute cauda equina syndrome in an adolescent male with Burkitt lymphoma, and spinal cord and cauda equina compression. Institutional review board approval was waived because of retrospective analysis of a single-case. Patient consented to the procedure and publication of his images.

CLINICAL PRESENTATION

An 18-year-old man, recently diagnosed with Burkitt lymphoma, presented to the emergency department with new-onset progressive bilateral lower extremity numbness and tingling (left > right) and urinary overflow incontinence. Pathology report is presented in Supplementary Digital Content 1 (Supplementary Figure 1, http://links.lww.com/NS9/A92). Approximately 2 months earlier, he noticed left-sided neck swelling and experienced an approximately 20 lbs weight loss. Within a month of symptoms, initial biopsy revealed diffused large B-cell lymphoma, and subsequent open lymph node biopsy confirmed Burkitt lymphoma. Positron emission tomography scan showed cervical adenopathy and multiple bone lesions compatible with lymphoma. Although chemotherapy was scheduled, he came to the emergency department 1-week before the planned start (Figure 1). On examination, the right lower extremity had full strength, while the left showed antigravity strength with weakness in the iliopsoas and quadriceps and only minimal antigravity strength in the anterior tibialis, extensor hallucis longus, and gastrocnemius. He had poor rectal tone and saddle anesthesia. Insertion of a Foley catheter drained over 1000 mL of urine.

FIGURE 1.

Flowchart depicting timeline of events from the initial symptomatic presentation to resolution of spinal compression symptoms. DA-R-EPOCH, Dose adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab, ED, emergency department.

A contrasted-MRI of the thoracic and lumbar spine showed large epidural masses at T5 to T7 causing Bilsky II cord compression,¹⁵ in addition to an epidural lesion at L5/S1 causing severe compression of the cauda equina and exiting left S1 nerve root (Figure 2A-2D).

FIGURE 2.

Preradiation MRI. A, Sagittal MRI of the thoracic spine showing a large epidural mass at T5 to T7. B, Axial MRI at the level of T6 showing moderate-to-severe thecal sac compression with complete effacement of the cerebrospinal fluid and indentation of the cord. C, Sagittal MRI of the lumbosacral spine showing an epidural mass at upper sacrum. D, Axial MRI at the level of L5 showing an epidural mass and thecal sac compression.

Neurosurgical Consultation

Neurosurgical opinion was sought for the imaging findings and acute cauda equina syndrome. Recognizing the lesion's radiosensitivity, neurosurgery urgently consulted radiation oncology. After discussion about the symptomatic lesion—thoracic cord compression vs cauda equina involvement with complete thecal sac effacement—the focal left foot weakness without proximal leg involvement was concluded to localize symptoms to the cauda equina lesion, warranting emergent treatment. Moreover, emergent radiation planning for thoracic spine was considered substantially more complex, owing to the presence of adjacent thoracic visceral structures. It was also agreed that surgery would likely be pursued if he did not improve after emergent radiation.

Radiation Treatment

Within 14 hours of admission, he underwent emergent radiotherapy, receiving a single 800 cGy fraction to the lumbosacral spine using a right posterior oblique/left posterior oblique beam arrangement with 15-MV photons on TrueBeam linear accelerator (Varian Medical Systems) (Figure 3A and 3B). Treatment planning was performed using Eclipse (Varian Medical Systems) with MRI-computed tomography image fusion of the thoracolumbar spine to define gross, clinical, and planning target volumes. Three-dimensional conformal external beam radiotherapy was selected rather than stereotactic radiosurgery or intensity-modulated radiotherapy, given the extent and geometry of disease and urgency of treatment planning. The biologically effective dose (BED) was calculated using the linear-quadratic model BED = nd (1 + d/α/β) based on the single-fraction dose of 800 cGy (n = 1, d = 8 Gy). An α/β ratio of 10 Gy was assumed for early-responding tumor tissue, consistent with standard radiobiological convention,^16,17 yielding BED of 14.4 Gy. A clamshell device was used to minimize testicular radiation exposure, given his reproductive age. He was initiated on the dose adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab regimen, per hematology-oncology recommendations and evidence-based guidelines.^18,19

FIGURE 3.

Radiation dose distribution on diagnostic computed tomography spine in A, axial plane and B, sagittal plane displayed in dose color wash with minimum dose at 50% (400 cGy) isodose line.

Postradiation Course

After radiation, he was closely monitored by neurosurgeons with twice-daily examinations to assess neurological improvement. On postradiation day-zero, his examination was unchanged; by day 1, left foot strength had slightly improved, with Foley catheter still in place. On postradiation day 2, left foot strength was nearly full and spontaneous voiding resumed, and by day 3, he was neurologically intact with low postvoid residuals. Per oncology team, repeat MRI, performed 4 days after radiation and chemotherapy, demonstrated resolution of the epidural soft-tissue mass and compression of the adjacent thecal sac in the midthoracic (T5-T7) and the lumbar (L5/S1) regions (Figure 4A-4D). Comparison of pre/postimaging is illustrated in Figure 5A-5D. The patient was discharged the following day without need for neurosurgical intervention and follow-up with the oncology team.

FIGURE 4.

Postradiation MRI. A, Sagittal MRI of the thoracic spine. B, Axial MRI at the level of T6. C, Sagittal MRI of the lumbar spine. D, Axial MRI at the level of L5 showing resolution of the intraspinal epidural soft tissue lesion and thecal sac compression in both the thoracic and lumbar regions.

FIGURE 5.

Preradiation axial MRI of the A, thoracic and C, lumbar spine showing an epidural mass and compression of the cord. Postradiation MRI of the B, thoracic and D, lumbar spine, 4 days after radiotherapy, showing resolution of the lesion.

DISCUSSION

This case highlights rapid-resolution of acute neoplastic cauda equina syndrome in an 18-year-old man with Burkitt lymphoma after a single radiotherapy session. He presented with progressive lower extremity numbness, tingling, and urinary retention. Imaging revealed spinal cord and cauda equina compression. Although surgery is commonly considered in cases of cauda equina compression, and may be the visceral reaction of a nontumor focused spine surgeon, the treatment team proceeded with emergent radiotherapy, resulting in rapid neurological and radiographical resolution. Four days after radiation, MRI showed resolution of epidural masses, with complete recovery of lower extremity strength and bladder function.

Spinal cord and cauda equina compression in adolescents rarely result from malignant tumors,²⁰ such as neuroblastoma, sarcomas, and lymphoma.^21,22 Few studies have described resolution of spinal Burkitt lymphoma with radiotherapy alone, with most advocating radiotherapy as a surgical adjunct.^2,20 Here, a single 3-dimensional conformal external-beam radiotherapy session resolved the epidural mass, decompressed the spinal cord, and alleviated neurological symptoms. Importantly, the neurosurgical team did not sign-off after the initial evaluation, and monitored him closely for any decline or lack of improvement, in which case, surgery would have been considered. The rapid response is consistent with the radiosensitivity of Burkitt lymphoma, attributed to its high mitotic rate and susceptibility to radiation-induced DNA damage.^23-25

This case underscores the role of emergent radiotherapy in managing radiosensitive tumors causing spinal cord or cauda equina compression, and emphasizes the importance of spine surgeons being well-versed in tumor biology and radiation sensitivity. Surgery was not needed in this patient but may have been indicated by some.^26,27 Importantly, if emergent radiation oncology services are unavailable, emergent surgery should be undertaken to maximize the likelihood of neurological recovery. Radiotherapy may serve as an effective, noninvasive alternative for reducing tumor burden and alleviating neurological symptoms. Further research into the timing-of-radiation with other treatment modalities is needed to inform more refined treatment protocols.

The rapid and concordant resolution of both thoracic and lumbosacral lesions after localized radiation also raises the possibility of an abscopal effect, wherein tumor deposits outside the irradiated field regress through radiation-induced activation of systemic antitumor immune responses. Although historically rare, abscopal responses have been increasingly recognized in hematological malignancies and in cases where radiation is delivered in close temporal proximity to systemic therapy.^28-30 In our patient, the high radiosensitivity of Burkitt lymphoma together with the early initiation of multiagent chemotherapy may have acted synergistically to potentiate such a systemic response, contributing to simultaneous improvement at anatomically distant spinal levels. Nonetheless, whether this represents a true abscopal phenomenon or an exceptionally profound radiosensitive effect remains uncertain.

As a single case-report, the observed rapid-resolution and favorable outcome may not be generalizable to all lymphoma patients with spinal cord involvement, and future studies should evaluate the role of radiotherapy in larger populations. In addition, there are no direct comparisons with alternative treatment modalities, and the absence of long-term follow-up limits conclusions regarding the relative efficacy of radiotherapy compared with surgery.

CONCLUSION

The case demonstrates that radiotherapy can rapidly and completely resolve spinal cord and cauda equina compression in Burkitt lymphoma, without surgery. Spine surgeons must understand the histology and radiosensitivity of spinal neoplastic processes. For radiosensitive tumors like lymphoma, emergent radiation can lead to rapid resolution of neurological deficits without requiring surgery.

Funding

This study did not receive any funding or financial support.

Disclosures

Dr Zuckerman reports being an unaffiliated neurotrauma consultant for the National Football League and a consultant for Medtronic, SI-Bone, and Carlsmed. The other authors have no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.

Supplementary Digital Content 1: Supplementary Figure. Anonymized histopathology report for the biopsy.