Diagnostic utility of FDG-PET in neurolymphomatosis: report of five cases

Primary neurolymphomatosis presenting as foot drop: A rare case report

ABSTRACT

Neurolymphomatosis (NL) is the direct infiltration of the peripheral nervous system (PNS) by lymphoma cells and represents the least common form of PNS involvement by lymphoma. Clinical presentation is varied, and early diagnosis remains challenging. Nerve biopsy remains the diagnostic gold standard, use of magnetic resonance imaging (MRI) and fluorodeoxyglucose-positron emission tomography (FDG-PET) may help in diagnosis and selecting targets for biopsy. We report an account of an older male patient who presented with subacute onset multifocal neuropathy involving bilateral lower limbs and left foot drop. The patient was initially misdiagnosed as chronic inflammatory demyelinating polyneuropathy; however radiological assessment revealed fusiform thickening of the L5 nerve root and biopsy from the site revealed extensive infiltration by diffuse large B cell type non-Hodgkin lymphoma (NHL). High index of suspicion is vital to ensure correct diagnosis, timely treatment, and to improve patient survival.

Thiotepa-based high-dose chemotherapy with autologous stem cell transplantation for neurolymphomatosis

Neurolymphomatosis (NL) is a rare clinical entity characterized by lymphomatous infiltration of the peripheral nervous system. According to recent retrospective data, consolidative high-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) may be beneficial for NL. However, few reports to date have discussed optimal conditioning regimens. Herein, we report two cases of NL in patients with relapsed intravascular large B-cell lymphoma who received consolidative thiotepa-containing HDC-ASCT. Case 1: A 56-year-old woman who relapsed 2 months after the first complete remission (CR) and underwent ASCT. Case 2: A 65-year-old woman who relapsed 8 months after the first CR and underwent ASCT. Both patients engrafted. Time to neutrophil engraftment was 10 and 12 days after HDC-ASCT, and CR was sustained for 26 and 18 months, respectively, as of the last follow-up. Although there is little evidence supporting the utility of thiotepa-based HDC-ASCT in patients with NL, the results of this case report suggest that further studies are warranted to determine its efficacy in this setting.

Clinical manifestations of, diagnostic approach to, and treatment of neurolymphomatosis in the rituximab era

Neurolymphomatosis (NL) is a rare manifestation of lymphoma, with limited evidence for optimal management. The largest patient series, 50 cases of lymphoma and leukemia, was published in 2010 with limited rituximab exposure. This study aims to evaluate the clinical presentation, diagnostic testing, and outcomes of NL in the rituximab era. Forty biopsy-proven cases of NL, in association with non-Hodgkin lymphoma (NHL), at the Mayo Clinic were retrospectively evaluated. B-cell NHL was associated with 97% of NL cases, of which diffuse large B-cell lymphoma (DLBCL) was the most common (68%). Primary NL, defined as neural involvement present at the time of diagnosis of lymphoma, was noted in 52% cases. Seventy percent of patients presented with sensorimotor weakness and neuropathic pain. Magnetic resonance imaging (MRI) was positive in 100% patients. Overall survival (OS) was significantly better for primary NL and NL associated with indolent lymphomas. Relapses were seen in 60% (24/40) of patients; 75% involved the peripheral or central nervous system at relapse. The use of rituximab in the frontline setting significantly impacted progression-free survival (PFS). Transplant consolidation was noted to be associated with improved OS. This study adds to the available literature on NL in the rituximab era. The overall outcomes have improved in recent years. In our experience, MRI and positron emission tomography/computed tomography may be required for accurate assessment of the extent of disease involvement and identification of an optimal biopsy site. The use of rituximab was associated with improvement in PFS, and autologous stem cell transplant was associated with OS.

Neurolymphomatosis: a single-center experience of neuromuscular manifestations, treatments, and outcomes

OBJECTIVES

Neurolymphomatosis (NL) is a disease characterized by the infiltration of malignant lymphocytes into the peripheral nervous system. We report clinical features, radiographic findings, modes of treatment, and outcomes of patients with NL.

METHODS

We retrospectively investigated patients with NL. We extracted data, including clinical features, magnetic resolution imaging (MRI), ¹⁸F-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scans, cerebrospinal fluid cytology findings, the results of electrodiagnostic studies, as well as patient treatments and outcomes.

RESULTS

Ten NL patients were identified. All patients reported pain/paresthesia and weakness in the affected area. The MRI scans were abnormal in eight out of nine patients with an enhancement of the spinal nerve root, plexus, peripheral nerve trunk, and cranial nerve. The FDG PET/CT scans were positive in all patients. Radiculopathy or radiculoplexopathy was the most common electrodiagnostic finding. Neurological improvement was observed in only three patients. The condition of the nine patients who underwent multimodality treatments for cancer eventually deteriorated and the patients died.

CONCLUSIONS

NL should be considered in the differential diagnosis of any type of neuropathy in patients with lymphoma. Because it could be confused with other neuropathies in lymphoma and various musculoskeletal diseases, a high index of suspicion and familiarity with clinical manifestation of NL are key. FDG PET/CT was the most sensitive diagnostic imaging modality to detect relevant neural invasion. The root within the spinal neural foramen was the most frequently affected neural structure. Early diagnosis of this rare neurologic manifestation of lymphoma may improve treatment outcomes.

Multiple secondary cauda equina non-Hodgkin's lymphoma: a case report and literature review

Background

Secondary central nervous system involvement of non-Hodgkin’s lymphoma (NHL) is rare and with poor prognosis, the most common pathological type is diffuse large B cell lymphoma (DLBCL). Although it can occur in any part of central nervous system, it rarely directly infiltrates the spinal cord or cauda equina.

Case presentation

We present the case of 64-year-old immunocompetent man with a worsening pain of waist and left lower extremity, accompanied by numbness and paresis of bilateral lower extremity for 20 days. His previous medical history included a resection of painless mass in the left groin in another hospital 7 months ago, and the pathological diagnosis was non-Hodgkin small B cell lymphoma. Gd-enhanced MRI and F-18 FDG PET-CT scan demonstrated multiple infiltrations in the cauda equina. During the operation, we removed as many as 11 subdural-extramedullary bean-size lesions involving multiple nerve roots. The paralysis of his left leg recovered rapidly after the operation. During the follow-up period of more than one year, he underwent standard R-CHOP chemical therapy, no evidence of recurrence was noted until the 13th month, the patient died because of intracranial relapse.

Conclusions

Imaging examination is important in the diagnosis of multiple secondary cauda equina non-Hodgkin’s lymphoma, and we highlight the significance of gadolinium-enhanced MRI and F-18 FDG-PET/CT in preoperative diagnosis as well as the previous history.

Peripheral nervous system involvement in lymphomas

The peripheral nervous system may be involved at any stage in the course of lymphoproliferative diseases. The different underlying mechanisms include neurotoxicity secondary to chemotherapy, direct nerve infiltration (neurolymphomatosis), infections, immune-mediated, paraneoplastic or metabolic processes and nutritional deficiencies. Accordingly, the clinical features are heterogeneous and depend on the localization of the damage (ganglia, roots, plexi, and peripheral nerves) and on the involved structures (myelin, axon, and cell body). Some clinical findings, such a focal or diffuse involvement, symmetric or asymmetric pattern, presence of pain may point to the correct diagnosis. Besides a thorough medical history and neurological examination, neurophysiological studies, cerebrospinal fluid analysis, nerve biopsy (in selected patients with suspected lymphomatous infiltration) and neuroimaging techniques (magnetic resonance neurography and nerve ultrasound) may be crucial for a proper diagnostic workup.

Limited efficacy of high-dose methotrexate in patients with neurolymphomatosis

Neurolymphomatosis (NL) is a rare manifestation of non-Hodgkin lymphoma, in which malignant cells infiltrate the peripheral nerves. Most patients are treated with high-dose methotrexate (HD-MTX)-based systemic chemotherapy regimens similar to patients with central nervous system lymphoma. However, because NL is rare, the efficacy of HD-MTX is largely unknown. We reviewed medical records of patients diagnosed with NL over the past 10 years and identified 18 patients. The underlying hematological malignancy was diffuse large B-cell lymphoma (DLBCL) in 10 patients (55.6%), intravascular large B-cell lymphoma in six (33.3%), and other types in two patients. Ten patients were treated with HD-MTX-based systemic chemotherapy; the response rates with and without HD-MTX-based chemotherapy were 100% (n = 10) and 85.7% (n = 6), respectively (P = 0.41). The median progression-free and overall survival rates of patients with versus without HD-MTX treatment were 6.4 vs. 8.5 months (P = 0.97) and 13.5 vs. 8.5 months (P = 0.63), respectively. Despite the initial favorable responses, rapid disease recurrence was observed in most patients administered HD-MTX-based chemotherapy. Our observations suggest that HD-MTX-based chemotherapy may have insufficient efficacy against NL, and that other therapeutic approaches are required to improve the outcomes of patients with this rare disease.

First pathological report of a de novo CD5-positive diffuse large B-cell lymphoma patient presenting with Guillain-Barré syndrome-like neuropathy due to neurolymphomatosis

Peripheral neuropathy occurs in approximately 5% of the patients with lymphoma. Two major causes of peripheral neuropathy associated with lymphoma are neurolymphomatosis and paraneoplastic neuropathy such as demyelinating neuropathy. The differential diagnosis between neurolymphomatosis and demyelinating neuropathy is difficult, because electrophysiological findings suggestive of demyelination are frequently observed even in patients with neurolymphomatosis. Here, we report a patient with de novo CD5-positive diffuse large B-cell lymphoma (DLBCL) who presented with Guillain-Barré syndrome (GBS)-like neuropathy. Demyelination due to paraneoplastic neuropathy was clinically suspected. However, autopsy demonstrated that the cause of the neuropathy was neurolymphomatosis. Clinical courses of neurolymphomatosis vary and neurolymphomatosis cases presenting with GBS-like neuropathy are reported. In addition, DLBCL is the most frequent histological type of malignant lymphoma that develops neurolymphomatosis. Furthermore, "CD5-positive" DLBCL may tend to develop neurolymphomatosis. If a patient with "CD5-positive" DLBCL develops peripheral neuropathy, neurolymphomatosis should be considered and imaging studies performed and, if possible, nerve tissue biopsy, regardless of clinical symptoms of the neuropathy. To our knowledge, this is the first report of a patient with de novo CD5-positive DLBCL with neurolymphomatosis who presented with GBS-like neuropathy.

Partial Conduction Block as an Early Nerve Conduction Finding in Neurolymphomatosis

BACKGROUND AND PURPOSE

Neurolymphomatosis is a rare manifestation of hematological malignancy and is characterized by direct infiltration of the peripheral nervous system. The objective of this study was to identify the clinical and electrophysiological features of neurolymphomatosis.

METHODS

We retrospectively analyzed the medical records of 13 patients with neurolymphomatosis. Seven (54%) of the patients were men, and the median age at symptom onset was 60.0 years.

RESULTS

The most common type of underlying malignancy was diffuse large B-cell lymphoma (69%). Twelve patients had painful asymmetric neuropathies. The median survival time after diagnosis was 7 months, and 12 patients died during the study period. Thirty-eight motor nerve conduction studies (NCSs) were performed in the affected nerves. Ten and 28 motor nerves were classified into the conduction-block and simple-axon-degeneration groups, respectively. The median time interval between symptom onset and the NCS was significantly shorter in the conduction-block group than in the simple-axon-degeneration group (p=0.032). However, no significant differences in the motor nerve conduction velocities, terminal latencies, and distal compound muscle action potential amplitudes were identified between the conduction-block and simple-axon-degeneration groups. The conduction-block group showed excessive temporal dispersion in only five of the ten NCSs (50%). Follow-up NCSs revealed that partial conduction blocks had changed into axonal degeneration patterns.

CONCLUSIONS

This is the first study to analyze the electrophysiological features of patients with neurolymphomatosis. Our findings showed that a partial conduction block is not rare and is an early nerve conduction abnormality in neurolymphomatosis.

Cauda equina syndrome secondary to neurolymphomatosis: Case report and literature review

Neurolymphomatosis is a rare disorder characterised by infiltration of neoplastic lymphocytes into the peripheral nervous system. A wide variety of symptoms can manifest depending on its nature and location, making its diagnosis a real challenge. Treatment is based on methotrexate, although various chemotherapy regimens are currently available for patients with systemic disease. We present the case of a male patient with neurolymphomatosis of the cauda equina, together with a review of all cases published to date.