Solitary extranodal lymphoma of sciatic nerve

A case report of surgical management of a solitary Non-Hodgkin's Lymphoma (NHL) arising from the proximal sciatic nerve

INTRODUCTION AND IMPORTANCE

Solitary lymphomas of the peripheral nervous system are very rare and lymphomas of the sciatic nerve are uncommon, especially those arising from the proximal part of the nerve. This case report describes a rare presentation of solitary B cell Non-Hodgkin's Lymphoma arising from the proximal sciatic nerve that was managed via surgical excision.

CASE PRESENTATION

A 28-year-old man experienced severe pain, motor and sensory issues in his right lower limb for a year. Magnetic Resonance Imaging identified a malignant peripheral nerve sheath tumour in the sciatic nerve involving S1 and S2 roots. No metastasis was found in CECT scans. Surgical resection via combined inguinal and gluteal approaches was followed by adjuvant chemoradiotherapy. Biopsy revealed diffuse large B-cell Lymphoma, non-Germinal Centre B-cell like subtype. Pain was reduced, and muscle power improved.

CLINICAL DISCUSSION

Neurolymphomatosis (NL) is a rare condition where lymphoma cells invade nerves. It mostly involves peripheral nerves, particularly the sciatic nerve. Cases often present with painful neuropathy. Treatment varies, with surgery followed by chemotherapy and radiotherapy used in this unique case involving the pelvic sciatic nerve. Individual patient factors guide management due to limited case data.

CONCLUSION

We present a unique case of neurolymphomatosis involving the proximal sciatic nerve, a rare occurrence. Surgical excision utilized a complex intra-abdominal and perineal approach, unprecedented in this context. This atypical presentation underscores the need to consider such cases in diagnosing unusual sensory motor neuropathies.

Neoplastic nerve lesions

Though metastasis and malignant infiltration of the peripheral nervous system is relatively rare, physicians should have a familiarity with their presentations to allow for prompt diagnosis and initiation of treatment. This article will review the clinical presentations, diagnostic evaluation, and treatment of neoplastic involvement of the cranial nerves, nerve roots, peripheral nerves, and muscle. Due to the proximity of the neural structure traversing the skull base, metastasis to this region results in distinctive syndromes, most often associated with breast, lung, and prostate cancer. Metastatic involvement of the nerve roots is uncommon, apart from leptomeningeal carcinomatosis and bony metastasis with resultant nerve root damage, and is characterized by significant pain, weakness, and numbness of an extremity. Neoplasms may metastasize or infiltrate the brachial and lumbosacral plexuses resulting in progressive and painful sensory and motor deficits. Differentiating neoplastic involvement from radiation-induced injury is of paramount importance as it dictates treatment and prognosis. Neurolymphomatosis, due to malignant lymphocytic infiltration of the cranial nerves, nerve roots, plexuses, and peripheral nerves, deserves special attention given its myriad presentations, often mimicking acquired demyelinating neuropathies.

Primary lymphoma of the medial cutaneous nerve of the forearm: the first case in a pure sensory nerve of the upper limb

Primary lymphoma of the peripheral nerve is very rare and occurs most frequently in sciatic nerves. We describe the first patient reported in literature with a primary lymphoma in a pure sensory peripheral nerve of the upper limb. A woman in her 40s, with painful swelling and dysaesthesias in her left forearm in the past 3 months, was presented at our unit. Clinical MRI and ultrasound findings revealed a lesion that showed signs of a peripheral nerve sheath tumour. After complete excision, morpho-pathological evaluation revealed a primary B-cell lymphoma. The patient underwent radiotherapy and at the last follow-up there were no signs of residual pathology. Peripheral neuropathy may be caused by a lymphoma involving the nerve. Hand surgeons have to distinguish primary lymphoma of the peripheral nerves from schwannoma for their different clinical behaviour.

Chronic sciatic nerve compression secondary to arteriovenous malformation: case discussion and literature review

Sciatic nerve symptomatology may arise from both intra- and extra-neural pathology, at any point along descent from the sacral plexus to its bifurcation. The potential aetiology is broad, ranging from degenerative spinal disease to muscle, bony and vascular pathology. We present an extremely unusual case of position and exercise-induced nerve compression secondary to arteriovenous malformation and review the potential extraspinal causes, many of which may be ameliorated by surgical excision or decompression. We further discuss the usefulness of diagnostic imaging, specific clinical tests and histopathological tools that may aid in management.

Primary B lymphoma tumor of the ulnar nerve. Case report

Primary lymphoma of a peripheral nerve is a very rare condition with only a few cases reported in the medical literature. Primary lymphoma of a peripheral nerve in the upper extremity was reported in only four cases in the English and French literature. We present a case of a 54-year-old man, in good health, without other medical conditions, who came to our unit complaining of paraesthesia in the ulnar territory of the hand. MRI investigation showed a mass situated in the ulnar nerve sheaths, in the lower third of the arm. Surgical exploration and excision were performed. Morphopathological results revealed a very uncommon tumor, a large B cell diffuse non-Hodgkin lymphoma, the second primary ulnar nerve lymphoma presented in the literature.

Early diagnosis and a better understanding of the pathogenesis of these tumors may change medical and surgical strategies, with further enhancement of survival rates.

Horner's Syndrome as Initial Manifestation of Possible Brachial Plexopathy Neurolymphomatosis

Introduction: Horner's syndrome is an established clinical finding unique to neoplastic brachial plexopathy.

Background: We present the case of a patient who developed Horner's syndrome as the first manifestation of neurolymphomatosis (NL) of the brachial plexus that did not have the usually associated bulky adenopathy/Pancoast syndrome phenotype.

Discussion: We discuss the clinical utility of Horner's syndrome with regards to brachial plexopathy of indeterminate etiology, as well as the utility of other diagnostic modalities in NL.

Concluding Remarks: NL, particularly of the brachial plexus, is particularly challenging to diagnose. MRI and CSF studies are often inconclusive. FDG-PET imaging can be difficult to get insurance to approve. The presence of Horner's syndrome in brachial plexopathy of indeterminate etiology, even in the absence of bulky adenopathy, should raise clinical suspicion of NL, possibly prompting such interventions as fascicular nerve biopsy.

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.

Plexus and peripheral nerve metastasis

Cancer in the form of solid tumors, leukemia, and lymphoma can infiltrate and metastasize to the peripheral nervous system, including the cranial nerves, nerve roots, cervical, brachial and lumbosacral plexuses, and, rarely, the peripheral nerves. This review discusses the presentation, diagnostic evaluation, and treatment options for metastatic lesions to these components of the peripheral nervous system and is organized based on the anatomic distribution. As skull base metastases (also discussed in Chapter 14) result in cranial neuropathies, these will be covered in detail, as well as cancers that directly infiltrate the cranial nerves. Particular emphasis is placed on the clinical, imaging, and electrodiagnostic features that differentiate neoplastic plexopathies from radiation-induced plexopathies. Neurolymphomatosis, in which malignant lymphocytes invade the cranial nerves, nerve roots, brachial and lumbosacral plexuses, and peripheral nerves, is a rare manifestation of lymphoma and leukemia. Diagnoses of neurolymphomatosis are often missed or delayed given its varied presentations, resulting in poorer outcomes. Thus this disease will also be discussed in depth.

Neurolymphomatosis of the peripheral nervous system: a case report and review of the literature

Neurolymphomatosis is a rare neurological syndrome in lymphomas. It is reported as infiltration of peripheral nerves by lymphoma. It is important to distinguish neurolymphomatosis from other types of neuropathies, particularly infectious and inflammatory conditions. However, it is difficult to isolate a cancer-related inflammatory vasculitis and mononeuritis multiplex without definitive histopathologic examination. In this report, we describe a case of non-Hodgkin's lymphoma involving the peroneal nerve and presenting as neurolymphomatosis.

Isolated sciatic neuropathy as an initial manifestation of a high grade B-cell lymphoma: A case report and literature review

Sciatic nerve neuropathy due to infiltrating of a high grade B-cell lymphoma is a very rare situation and has not often been reported. We report a case with a previous history of indolent lymphoma who presented with isolated sciatic nerve neuropathy and was found to have diffuse large B cell lymphoma involving the sciatic nerve. Although the current case is not a primary sciatic nerve lymphoma given the systematic involvement shown on MRI and PET/CT scan, the case represents a neurolymphomatosis of the sciatic nerve given the direct invasion of the lymphoma cells into the sciatic nerve. Due to the rarity of this condition, we subsequently reviewed related literatures.

Primary Neurolymphomatosis Presenting With Polyradiculoneuropathy Affecting One Lower Limb

OBJECTIVES

We report a case of primary neurolymphomatosis (NL) with unusual presentation and excellent treatment response.

METHODS

Chart review.

RESULTS

A 64-year-old woman presented with 2 months of progressive pain, weakness, and numbness in her right leg. Nerve conduction study/electromyogram suggested a right lumbosacral radiculoplexus neuropathy with associated acute right peroneal neuropathy at the fibular head. L/S spine and right leg magnetic resonance imaging showed thickening and contrast enhancement of the right S1 nerve root and the right distal sciatic, tibial, and common peroneal nerves, as well as a lobular enhancing lesion of the right superficial peroneal nerve. Whole-body fludeoxyglucose-positron emission tomography scan showed no other lesions. A right superficial peroneal nerve lesion biopsy revealed infiltration of the nerve by diffuse large B-cell lymphoma. The lymphoma cells expressed BCL2 but not CD10, suggesting an origin in peripheral blood not lymph nodes. Despite the expression of BCL2, which is considered as a poor prognosis marker, our patient responded very well to the combined radiotherapy and chemotherapy with the R-MPV (rituximab, MTX, procarbazine, and vincristine) regimen. The patient showed marked clinical improvement and complete resolution of lymphoma lesions on the PET scan.

CONCLUSIONS

Our case broadens the clinical spectrum and illustrates the importance of early diagnosis and aggressive treatment of primary NL.

Primary multifocal lymphoma of peripheral nervous system: case report and review of the literature

INTRODUCTION

Primary lymphomas of peripheral nerves are extremely rare, and only a few cases have been reported.

METHODS

We describe the clinical, neurophysiological, radiological, and pathological findings in a 61-year-old woman affected by primary multifocal lymphoma of the peripheral nervous system without systemic involvement.

RESULTS

Fascicular left femoral nerve biopsy was decisive for the diagnosis of diffuse large B-cell non-Hodgkin lymphoma. Magnetic resonance imaging, fluorine-18 fluorodeoxyglucose positron emission tomography computed tomography, and nerve ultrasound contributed to the diagnosis.

CONCLUSIONS

Primary lymphoma of peripheral nerves (PLPNs) is a rare but potentially treatable condition, which is frequently misdiagnosed. In the literature, there are very few descriptions of PLPNs, most of which are mononeuropathies. The possibility of a neuropathy associated with lymphoma should be considered in patients with poor response to treatment and severe pain symptoms.

Extranodal lymphoma with peripheral nervous system involvement in a dog

An 8-year-old neutered female Cavalier King Charles spaniel was evaluated for progressing right forelimb lameness. Magnetic resonance imaging revealed that the right-side radial nerves and the caudal brachial plexus were swollen. The histological and molecular biological diagnosis by partial biopsy of the C8 spinal nerve was T-cell lymphoma. Coadministration of lomustine and irradiation was started. However, this therapy was ineffective. At necropsy, neoplastic tissues were seen extending into the subarachnoid space of the spinal cord, liver, pancreas and kidneys as gross findings. A large mass was also identified occupying the caudal thorax. Histologic findings included infiltration in these organs and the mass by neoplastic lymphocytes. To date, involvement of peripheral nerves (neurolymphomatosis) is rarely reported in veterinary species.

A rare reason of foot drop caused by primary diffuse large b-cell lymphoma of the sciatic nerve: case report

INTRODUCTION

Primary central nervous system lymphomas account for 2% of all malignant lymphomas. Although the involvement of peripheral nerves has been previously described as a dissemination of systemic lymphomas or a direct extension to the nerve trunk from contiguous lymphomas, primary involvement of the sciatic nerve is extremely rare.

CASE

To the best of our knowledge, the primary localization of lymphoma within sciatic nerve has been reported only nine times. We report, a very rare example of a primary diffuse large B-cell lymphoma of the sciatic nerve.

DISCUSSION

The patient presented with atypical sciatica. Such symptoms can be misdiagnosed as lumbar disc pathology and magnetic resonance imaging and electrophysiological studies avoid this misinterpretation.

Reversal of neurological deficit after chemotherapy in BCL-6–positive neurolymphomatosis

Neurolymphomatosis, the infiltration of the peripheral nervous system (PNS) by malignant lymphatic cells, is a rare condition whose prognosis and treatment are not fully characterized. The authors report the case of a 69-year-old, previously healthy man who had a 1-month history of progressive pain in his right arm and associated weakness of several muscles of the right upper extremity when they first examined him. Initial MR imaging of the right brachial plexus showed no abnormalities, but over 3 months, symptoms gradually progressed to almost complete plegia of his right upper extremity. Subsequent MR imaging of his right brachial plexus showed an enhancing mass of the posterior cord of the plexus that encroached on the other cords. Positron emission tomography confirmed the presence of a hypermetabolic lesion in the right axillary region and also detected an asymptomatic hot spot in the gastric wall. Biopsy of the gastric lesion demonstrated a CD20+, diffuse large B-cell lymphoma that was immunohistochemically positive for BCL-6 and negative for p16. The patient underwent 6 cycles of dose-adjusted etoposide-vincristine-doxorubicin-cyclophosphamide-prednisone (EPOCH) and rituximab, intermixed with 3 cycles of high-dose intravenous and intrathecal methotrexate, and followed by 6 monthly doses of rituximab for consolidation. Follow-up MR imaging and PET of the plexus showed complete radiological response after 3 months of treatment, as demonstrated by normalization of brachial plexus caliber, contrast enhancement, and metabolic activity.

Twenty-eight months after symptom onset and 20 months after beginning therapy, the patient was disease-free, had recovered most upper extremity neurological function, and had only minimal remaining weakness of the right wrist and finger extension.

Lymphome T révélé par une mononeuropathie multiple : étude d’un cas avec revue de la littérature

INTRODUCTION

Lymphoma occasionally affects the peripheral nervous system. Neuropathy usually appears in patients with known lymphoma but rarely represents the initial manifestation of underlying malignancy. We report a case in which mononeuritis multiplex (MM) was the dominant feature in the clinical presentation of a peripheral T-cell non-Hodgkin lymphoma (NHL).

OBSERVATION

A 32-year-old man suffered from an asymmetric progressive sensory-motor peripheral neuropathy. The left peroneal nerve was affected first, then the left median nerve after one month, followed by the left trigeminal nerve ten months later. The electrophysiological study confirmed the diagnosis of axonal sensory-motor MM. Mediastinal adenopathies, splenomegaly, pancytopenia and inflammatory syndrome were also found. An osteo-medullary biopsy showed a T-cell NHL. Nerve biopsy study found an inflammatory lymphoid infiltration without malignant cell supporting the hypothesis of an inflammatory pathogenic process. Chemotherapy including cyclophosphamide, hydralazine, vincristine and prednisone were administered monthly during 8 months. No improvement was obtained.

DISCUSSION

It must be emphasised that this case is an uncommon one. On the one hand, NHL is rarely associated with MM and on the other hand, it can exceptionally be revealed by a MM. We were able to find 30 reported cases of distal neuropathy revealing a NHL including, 8 mononeuritis simplex, 9 MM and 13 polyneuropathies. Polyradiculoneuritis cases were excluded from this study because the neuropathy is usually caused by a meningeal infiltration. The neuropathy was in the majority of the cases chronic and axonal. The lymphoma was more often B-cell than T-cell. The B-cell lymphoma was frequently associated with a poor prognosis. All mechanisms were present with a predominance of neurolymphomatosis.

Primary sciatic nerve lymphoma: a case report and review of the literature

A patient with primary B cell non-Hodgkin's lymphoma of the sciatic nerve is described. He presented with neuropathic symptoms in the left leg, initially diagnosed as tarsal tunnel syndrome. Magnetic resonance imaging (MRI) identified the abnormality in the sciatic nerve. A fascicular biopsy of the sciatic nerve showed a diffuse large B cell non-Hodgkin's lymphoma. The patient was treated with chemotherapy and rituximab (anti-CD20 monoclonal antibody). Four months later he was in remission, and remains so 48 months from presentation. Primary lymphoma of single peripheral nerves may be a unique subtype of extranodal lymphoma, which usually follows an aggressive course and has a variable response to current therapeutic strategies. MRI is useful, alongside electrophysiological studies, in patients with atypical peripheral nerve symptoms.

Lymphoma and peripheral neuropathy: a clinical review

Lymphoma occasionally affects the peripheral nervous system. When it does, the diagnosis can be elusive since many patients present without known lymphoma. Most peripheral nerve complications are due to non-Hodgkin's lymphoma (NHL), which infiltrates nerves causing axonal damage. This disorder can affect nerve roots and cranial nerves, often associated with lymphomatous meningitis. NHL may also infiltrate peripheral nerves and cause plexopathy, mononeuropathy, or generalized neuropathy. These neuropathies may resemble an asymmetric mononeuropathy multiplex or a generalized disorder such as chronic inflammatory demyelinating polyradiculoneuropathy. When NHL infiltrates diffusely, the term neurolymphomatosis is used. Hodgkin's lymphoma (HL), by contrast, rarely infiltrates nerves. More often, HL causes immunological disorders of the peripheral nervous system such as inflammatory plexopathy or Guillain-Barré syndrome. Other rare lymphomas such as intravascular lymphoma and Waldenstrom's macroglobulinemia can also affect peripheral nerves in specific ways. In addition, other malignant and nonmalignant lymphoproliferative disorders enter into the differential diagnosis of lymphomatous neuropathy. This review discusses the multiple peripheral nerve presentations of lymphoma from the clinician's point of view and provides a guide to the evaluation and diagnosis of these uncommon, challenging disorders.

Operative outcomes of 546 Louisiana State University Health Sciences Center peripheral nerve tumors

The surgical management of benign PNSTs and some other benign tumors can result in successful outcomes. Schwannomas and nonplexiform neurofibromas can be resected with minimal deficit by sparing all but the fascicles entering and exiting the tumor. These fascicles, if not functional by NAP testing, can be resected, and the tumor can be removed. Surgery to remove other benign lesions, such as intraneural ganglion cysts, hemangiomas,and ganglioneuromas, has become more timely. The desmoid tumor, although microscopically benign, is locally and regionally invasive, and chemotherapy and radiation therapy may need to be used as adjunctive therapy. Neurogenic sarcomas and other malignancies have high morbidity and mortality despite aggressive limb ablation or limb-sparing surgery with adjunctive therapy. Thus, surgery involving decompression as well as the most complete resection possible remains the essential initial step in the management of most malignancies.

Magnetic resonance imaging in the diagnosis of lymphoma involving the brachial plexus in a cat

An 11-year-old, neutered, female Domestic Long Hair cat had a 3-week history of left forelimb lameness. Conscious proprioception and postural reflexes were absent on the left thoracic limb. The cat had slightly reduced placing and hopping responses on the left pelvic limb, absent cutaneous trunci muscle reflex on the left side, and left triceps muscle atrophy. Magnetic resonance imaging revealed a 2 x 2 x 2 cm mass in the region of the left brachial plexus. The cat was treated by left forelimb amputation and hemilaminectomy. Histopathology of the brachial plexus revealed lymphoma.

Primary lymphoma of peripheral nerve: report of four cases

Lymphoma presenting as a solitary tumor of peripheral nerve is exceedingly rare, with only six previously reported cases. The authors describe an additional four cases of primary lymphoma of peripheral nerve involving the sciatic nerve (two cases), the radial nerve, and the sympathetic chain and spinal nerve. The patients were two men and two women with an average age of 55.5 years. All tumors were high-grade B-cell lymphomas. Two patients experienced relapse of disease with involvement of other nervous system sites and died of lymphoma. One patient is alive with stable local disease at 57 months. The fourth patient is alive with no evidence of disease at 54 months. Expression of neural cell adhesion molecule (CD56) has been reported to correlate with an increased incidence of central nervous system involvement in peripheral T-cell lymphoma; all their cases were CD56 negative. Recent reports indicate a high proportion of primary brain lymphomas show loss of CDKN2A/p16 gene expression. Therefore, CDKN2A/p16 was evaluated in their patients both by polymerase chain reaction and by immunohistochemistry for the p16 protein. The authors found homozygous deletion of the CDKN2A/p16 gene in one of three patients studied, confirmed immunohistochemically by absent staining for p16. The fourth patient showed absent staining for p16, suggesting inactivation of the gene in this case as well. The two patients with p16 loss both died of lymphoma, whereas the two patients with normal p16 expression are alive. Primary lymphoma of peripheral nerve is a rare neoplasm, usually of large B-cell type, has a variable prognosis, and appears to have less consistent loss of p16 expression than primary central nervous system lymphoma.

Solitary sciatic nerve lymphoma as an initial manifestation of diffuse neurolymphomatosis. Case report and review of the literature

Solitary peripheral nerve lymphomas are exceedingly rare primary manifestations of diffuse peripheral nervous system or central nervous system (CNS) lymphomatosis. A 52-year-old man presented with progressive weakness in gastrocnemius and anterior tibial muscle function, which was associated with radiating pain in the right leg. Magnetic resonance imaging studies revealed a solitary fusiform tumor, extending from the sciatic nerve, at the level of the lesser trochanter of the femur, into the posterior tibial nerve below the popliteal fossa. Intraoperative gross examination found that the tumor diffusely expanded the nerve, but did not extend from or into surrounding muscle or tendons. The final histological diagnosis was a solitary extranodal lymphoma (Burkittlike high-grade B-cell lymphoma). Postoperative staging did not reveal evidence of lymphomatous involvement of other organs, but additional chemo- and radiotherapies were administered. Four months after the surgical biopsy, the patient presented with a right facial nerve palsy. The results of cytological examination of cerebrospinal fluid were positive for the presence of atypical lymphocytes, which was consistent with apparently progressive neurolymphomatosis; however, the results of radiological studies were negative for systemic progression. The patient underwent intrathecal chemotherapy followed by systemic myelosuppressive chemotherapy with bone marrow rescue, but died of respiratory failure while still receiving treatment. Postmortem examination revealed extensive lymphomatosis in the peripheral nerves and spinal nerve roots without evidence of cranial nerve, CNS, or other organ system involvement. The aggressive biological characteristics of these tumors, their management, and pertinent literature are reviewed.

Sciatic neuropathy

Injuries to the sciatic nerve cause neurologic deficits in the peroneal and tibial nerve distributions. Interestingly, most injuries result in more severe deficits to the peroneal division compared to the tibial division. Thus, it can sometimes be difficult to distinguish sciatic neuropathy from peroneal neuropathy. The long course of the sciatic nerve leaves it vulnerable to nerve injury from a variety of causes. Most sciatic neuropathies are acute in onset, such as from hip arthroplasty and hip fracture or dislocation, but some occur from prolonged compression, such as during coma. Entrapment of the sciatic nerve by mass lesions or by the piriformis muscle is relatively rare.

Primary non-Hodgkin's lymphoma of brachial plexus

We report the case of a 65-year-old man with non-Hodgkin's lymphoma (NHL) not only in the brachial plexus but also in the central nervous system and parotid gland. He was referred to our hospital for evaluation of a right parotid mass. He also presented with bilateral facial palsy and paralysis of the left superior limb. Computed tomography scan and magnetic resonance imaging revealed mass lesions in the right parapharyngeal space, the deep lobe of the right parotid gland. and the left brachial plexus. A gallium-67 citrate scan demonstrated abnormal uptake in the left brachial plexus. These symptoms and lesions improved during steroid therapy. However, the symptoms worsened again after steroid therapy was discontinued. We performed a right parotidectomy to confirm the diagnosis. Histopathological study revealed NHL. He was treated with combination chemotherapy, and most of the lesions and symptoms, except bilateral facial palsy, improved. Despite follow-up treatment, a brain metastasis occured, and he died 16 months after the onset of symptoms.

Mononeuropathy multiplex due to infiltration of lymphoma in hematologic remission

We report a case of progressive mononeuropathy multiplex in a patient with lymphoma in hematologic remission. At the time of presentation there was no evidence of meningeal or central nervous system metastasis. At autopsy, extensive infiltration of tumor cells was found in both femoral nerves. We review the literature pertaining to multifocal malignant lymphoid infiltration of peripheral nerves, which can occur during hematologic remission or in the absence of any evidence of systemic lymphoma.

Primary non-Hodgkin's lymphoma of the sciatic nerve followed by localization in the central nervous system: case report and review of the literature

OBJECTIVE AND IMPORTANCE

A unique case of primary non-Hodgkin's lymphoma of the sciatic nerve followed by multiple loci in the central nervous system is described.

CLINICAL PRESENTATION

The lesion occurred in a 44-year-old immunocompetent man with a palpable mass in the left popliteal fossa and a 10-month history of progressive weakness and numbness of the left foot. The tumor was a diffuse large lymphoma of B-cell origin of an intermediate grade of malignancy according to the criteria of the International Working Formulation.

INTERVENTION

Because diagnosis of the malignant lymphoma was performed on frozen section, resection of the nerve trunk was avoided. The patient was treated with radiotherapy and chemotherapy. At 6 months after the discovery, biopsy, and treatment of the sciatic nerve lymphoma, other lesions demonstrating the same histological features were observed in the central nervous system. The patient died 4 years and 2 months after presentation as a result of the central nervous system lesions and without clinical evidence of systemic extraneural localization.

CONCLUSION

A review of the literature indicates that primary peripheral nerve lymphomas occur in the sciatic nerve. These cases, and the case described in our study, share common clinicopathological findings that justify discussing them separately as distinct entities.

Solitary T-cell lymphoma of the sciatic nerve: case report

In lymphoproliferative disorders, primary involvement of the peripheral nerve is rare. This report describes a very rare case of a solitary extranodal T-cell lymphoma of the sciatic nerve. Magnetic resonance imaging and gallium scintigraphy were useful for the identification of the lesion of the sciatic nerve. The histological analysis of an open-biopsy specimen disclosed a T-cell lymphoma (non-Hodgkin's lymphoma, lymphoblastic type). Radiotherapy and chemotherapy resulted in a partial regression of the disease.

The electrophysiologic features of sciatic neuropathy in 100 patients

We reviewed the electrophysiologic data of 100 consecutive patients with sciatic neuropathy in order to better understand this disorder. Most patients (93%) had electrodiagnostic signs of significant axonal loss. Seven patients had predominantly signs of demyelination; 6 were due to compression and 1 was idiopathic. The peroneal division was more severely affected than the tibial division in 64% of patients. Tibialis anterior EMGs were abnormal in 92%, and the EDB CMAP was low in amplitude or absent in 80%. CMAP and SNAP amplitudes and EMGs were all normal in the tibial division in 12%. In contrast, the tibial division was more severely affected in only 8 patients. Of those, 5 were due to thigh trauma (gunshot wounds or femur fracture), 2 from gunshot wounds to the hip, and the other was chronic and idiopathic. Sciatic neuropathies are commonly, but not always, axonal loss lesions that affect the peroneal greater than tibial division.

[Peripheral neuropathies and hemopathies]

In our experience, the incidence of an association between peripheral neuropathy and hemopathy is around 7%. The corresponding nerve involvement may reveal or complicate a known hemopathy. The exact cause-effect relationship is not always easy to identify. We discuss here the peripheral nerve complications of acute leukemia, myeloproliferative disorders, monoclonal dysglobulinemia, non-Hodgkin's malignant lymphoma and Hodgkin's disease. The peripheral neuropathy arising in cases of monoclonal dysglobulinemia, non-Hodgkin's malignant lymphoma have most benefited from ultrastructural examination and advances in immunological and immunocytochemical techniques. Accurate determination of the lesional mechanism should help devise appropriate therapeutic strategies.

[Primary malignant lymphoma localized in the trunk of the ulnar nerve at the elbow. A case report]

The subject of this report is the exceptional observation of an ulnar nerve syndrome in the right elbow induced by the intra and extra neural development of a primary malignant lymphoma. The patient is a man of sixty-eight. The syndrome evolved over one year. The electromyogram showed marked slowing of the conduction speed on the ulnar nerve. The operation unabled us only to carry out a partial biopsy resection. Complementary chemotherapy was then carried out making a survival of two years and seven months possible without any sign of recurrence or other sites. We have only been able to locate two other published cases of primary malignant lymphoma developing on a nerve trunk and more precisely in on the level of the sciatic nerve. No other case has been described in a nerve trunk in the upper limb.

Primary central nervous system lymphomas--an update

Primary CNS lymphomas (PCNSL), until recently representing about 1% of all brain tumors, show dramatically increased incidence both in high-risk groups (immunocompromised, AIDS) and in the general population. They are extranodal diffuse non-Hodgkin's lymphomas, the morphology and classification of which are identical to those of systemic lymphomas, although PCNSL show different biological behavior and diagnosis according to the New Working Formulation and updated Kiel classification may be difficult. The majority are large B cell variants of high-grade malignancy; low-grade subtypes and T cell lymphomas are rare. Sixty per cent occur in the supratentorial space (hemispheres, periventricular) and 12% in the posterior fossa; 30% are multiple (50%-70% in AIDS). PCNSL show a male preponderance with a peak incidence in the 5th-7th decade (3rd-4th in AIDS). The duration of diffuse or focal clinical symptoms averages 1-2 months. Computed tomography and magnetic resonance imaging scans show single or multiple or diffuse, often typical lesions. Diagnosis is achieved by evaluation of stereotactic biopsy material or cerebrospinal fluid cytology using immunocytological markers. Current therapy in immunocompetent patients, radiation plus corticosteroids and pre- or postradiation polychemotherapy, shows response rates of 85% with a median survival of 17-44 months, a prognosis similar to that for glioblastoma. Meningeal PCNSL is treated with intrathecal methotrexate or cytosine arabinoside. Transliquoral seeding of PCNSL is frequent, distant metastases occurring in 6%-8%. Therapy of AIDS-related PCNSL makes use of radiation and corticosteroids, and rarely of chemotherapy. The pathogenesis of PCNSL is unknown, but Epstein-Barr virus may be a contributory factor.

Leukemic relapse presenting as sciatic nerve involvement by chloroma (granulocytic sarcoma)

A relapse of acute nonlymphocytic leukemia in a child presented as subacute mononeuropathy involving the sciatic nerve. Surgical exploration showed a chloroma (granulocytic sarcoma) of the distal sciatic nerve, but resection and irradiation did not lead to recovery of nerve function or complete resolution of the patient's symptomatic neuropathic pain. This case represents a rare neurologic complication of what is currently an uncommon presentation for leukemic relapse, and may be the only reported case of chloromatous involvement of the peripheral nervous system (PNS) without coexisting epidural or leptomeningeal leukemia.