Paraneoplastic syndromes of the spinal cord, nerve, and muscle

Paraneoplastic Syndrome Case Presented As Nystagmus and Ataxia

The incidence of paraneoplastic syndrome (PNS) is on the rise, attributed to the growing detection of antibody modalities in both the serum and cerebrospinal fluid (CSF). PNS can occur as different neurological symptoms. The revised guidelines streamline the diagnostic approach but identifying PNS still requires the detection of neurological manifestations concurrent with cancer, along with the presence of specific PNS autoantibodies.

Epidemiology of paraneoplastic neurologic syndromes

Paraneoplastic neurologic syndromes (PNS), initially depicted as seemingly cryptic remote manifestations of malignancy, were first described clinically in the early 20th century, with pathophysiologic correlates becoming better elucidated in the latter half of the century. There remain many questions not only about the pathophysiology but also regarding the epidemiology of these conditions. The continuous discovery of novel autoantigens and related neurologic disease has broadened the association in classical PNS to include conditions such as paraneoplastic cerebellar degeneration. It has also brought into focus several other neurologic syndromes with a putative neoplastic association. These conditions are overall rare, making it difficult to capture large numbers of patients to study, and raising the question of whether incidence is increasing over time or improved identification is driving the increased numbers of cases. With the rise and increasing use of immunotherapy for cancer treatment, the incidence of these conditions is additionally expected to rise and may present with various clinical symptoms. As we enter an era of clinical trial intervention in these conditions, much work is needed to capture more granular data on population groups defined by socioeconomic characteristics such as age, ethnicity, economic resources, and gender to optimize care and clinical trial planning.

Diagnosis and Treatment of Paraneoplastic Neurologic Syndromes

Paraneoplastic antibody syndromes result from the anti-tumor antibody response against normal antigens ectopically expressed by tumor cells. Although this antibody response plays an important role in helping clear a nascent or established tumor, the engagement of antigens expressed in healthy tissues can lead to complex clinical syndromes with challenging diagnosis and management. The majority of known paraneoplastic antibody syndromes have been found to affect the central and peripheral nervous system. The present review provides an update on the pathophysiology of paraneoplastic neurologic syndromes, as well as recommendations for their diagnosis and treatment.

CV2/CRMP5-antibody-related Paraneoplastic Neurologic Syndrome Associated with Gastrointestinal Stromal Tumor

Paraneoplastic neurological syndrome (PNS) is a heterogeneous group of neurological disorders caused by immune-mediated inflammatory mechanisms. We herein report a 77-year-old man with CV2/CRMP5-antibody-related PNS associated with a gastrointestinal stromal tumor (GIST). He was admitted for forgetfulness and delusional behavior. His neurological symptoms were subacute, and a whole-body examination revealed a gastric GIST. Serology showed CV2/collapsin response mediator protein (CRMP)-5 antibodies. Partial gastrectomy was performed for the GIST, and the neurological symptoms and serum CV2/CRMP5 antibodies disappeared. No relapse has occurred since the surgery. PNS should be considered in patients with subacute neurological disorders.

PARANEOPLASTIC SYNDROMES REVIEW: THE GREAT FORGOTTEN ONES

Paraneoplastic syndromes (PNS) are a group of disorders that can affect the oncologic patient, and which are not directly attributable to tumour invasion, tumour compression or metastasis. In fact, they are due to tumour secretion of functional hormones or peptides or are related to immune cross-reactivity with the host tissue. These syndromes are called paraneoplastic because the components that cause them do not derive from the organ or tissue of origin, but from the neoplasm suffered by the patient. It is estimated that 10-15% of people with cancer suffer from a PNS.(1) PNS is the second direct cause of death (27% of cases) in cancer patients, after cancer itself. Consequently, it is of remarkable importance to recognize and treat SPNs specifically.(2) In view of the above, the aim of this article is to review the state of the art in neurological, haematological, endocrine, and dermatological paraneoplastic syndromes. It is a review in which the most relevant PNS and their symptomatology are described, inquiring into their diagnosis and treatment.

Approach to Neuropathic Pain

Neuropathic pain is a common chief complaint encountered by neurologists and primary care providers. It is caused by disorders involving the somatosensory nervous system. The clinical evaluation of neuropathic pain is challenging and requires a multifaceted systematic approach with an emphasis on a thorough history and physical examination to identify characteristic signs and symptoms. Ancillary laboratory investigations, targeted imaging, and electrodiagnostic studies further help identify underlying etiologies to guide specific treatments. Management of neuropathic pain encompasses treating the underlying pathology as well as symptomatic control with nonpharmacological, pharmacological, and interventional therapies. Here, we present an approach to help evaluate patients with neuropathic pain.

Paraneoplastic Diseases of the Central Nervous System

Paraneoplastic neurological syndromes are nonmetastatic complications of malignancy secondary to immune-mediated neuronal dysfunction or death. Pathogenesis may occur from cell surface binding of antineuronal antibodies leading to dysfunction of the target protein, or from antibodies binding against intracellular antigens which ultimately leads to cell death. There are several classical neurological paraneoplastic phenotypes including subacute cerebellar degeneration, limbic encephalitis, encephalomyelitis, and dorsal sensory neuropathy. The patient’s clinical presentations may be suggestive to the treating clinician as to the specific underlying paraneoplastic antibody. Specific antibodies often correlate with the specific underlying tumor type, and malignancy screening is essential in all patients with paraneoplastic neurological disease. Prompt initiation of immunotherapy is essential in the treatment of patients with paraneoplastic neurological disease, often more effective in cell surface antibodies in comparison to intracellular antibodies, as is removal of the underlying tumor.

P/Q and N-type Voltage-gated Calcium Channel Binding Antibodies Associated with Paraneoplastic Chorea and Mixed Invasive Ductal and Lobular Carcinoma of the Breasts in an Elderly Patient

Paraneoplastic neurologic syndromes are a group of immune-mediated, cancer-associated disorders affecting the nervous system. While these syndromes are not understood fully, they are reportedly caused by an immune response against common antigens expressed by the cancer and nervous system. We describe the course of a patient who suffered paraneoplastic chorea before being diagnosed with breast cancer. A 70-year-old female presented with complaints of “shaking” movements of her head. History, physical exam findings, and preliminary workup ruled out the hereditary, metabolic, and infectious causes of chorea while brain computed tomography (CT) ruled out chorea due to a basal ganglia lesion. A paraneoplastic antibody panel identified N-type and P/Q-type voltage-gated (V-G) calcium channel binding antibodies. Subsequent age-appropriate cancer screening, which included a colonoscopy and screening mammograms, identified breast cancer. The patient had bilateral total mastectomies. Histopathology confirmed mixed invasive ductal and lobular carcinoma that was estrogen receptor positive, progesterone receptor positive, and human epidermal growth factor receptor 2 negative. In addition to mastectomies, the patient received adjuvant anastrozole. The appearance of choreiform movements before the diagnosis of breast cancer and the presence of paraneoplastic antibodies indicated that the chorea was most likely paraneoplastic in nature. Our patient continues to have choreiform movements despite undergoing bilateral mastectomies and receiving anastrozole, prednisone, and rituximab. We suspect the mastectomies and immune modulating therapies have not had an effect on her chorea because her P/Q and N-type V-G calcium channel binding antibodies may be intracellular. This case of paraneoplastic chorea associated with breast cancer is unusual. To the best of our knowledge, only one other case of paraneoplastic chorea associated with breast cancer has been reported in the English literature.

Anti-glutamic acid decarboxylase antibody positive neurological syndromes

A rare kind of antibody, known as anti-glutamic acid decarboxylase (GAD) autoantibody, is found in some patients. The antibody works against the GAD enzyme, which is essential in the formation of gamma aminobutyric acid (GABA), an inhibitory neurotransmitter found in the brain. Patients found with this antibody present with motor and cognitive problems due to low levels or lack of GABA, because in the absence or low levels of GABA patients exhibit motor and cognitive symptoms. The anti-GAD antibody is found in some neurological syndromes, including stiff-person syndrome, paraneoplastic stiff-person syndrome, Miller Fisher syndrome (MFS), limbic encephalopathy, cerebellar ataxia, eye movement disorders, and epilepsy. Previously, excluding MFS, these conditions were calledhyperexcitability disorders. However, collectively, these syndromes should be known as "anti-GAD positive neurological syndromes." An important limitation of this study is that the literature is lacking on the subject, and why patients with the above mentioned neurological problems present with different symptoms has not been studied in detail. Therefore, it is recommended that more research is conducted on this subject to obtain a better and deeper understanding of these anti-GAD antibody induced neurological syndromes.

Malignancy in Guillain-Barré syndrome: A twelve-year single-center study

The relationship between Guillain-Barré syndrome (GBS) and malignancy is uncertain. We retrospectively analyzed data of 118 consecutive patients admitted with GBS from Birmingham, U.K. (2001-2012). We calculated relative cancer risk using different definitions and determined characteristics of malignancy-associated GBS. Malignancy was globally commoner in our GBS cohort compared to the general population (odds ratio: 2.08; CI: 1.06-3.71; p=0.036). However, this was unconfirmed if paraneoplastic criteria were applied. GBS patients with cancer were significantly more likely to be older (p=0.043), hyponatremic (p=0.037) and demonstrate more axonal loss (p<0.05). Cerebrospinal fluid (CSF) protein levels were lower in the malignancy group (p=0.002) and neurological improvement less likely (p=0.023). In-patient mortality was significantly higher in patients with malignancy (p<0.01). We conclude global cancer risk is higher in GBS than in the general population, although definition-dependent. Malignancy requires consideration in elderly, hyponatremic subjects with normal CSF protein, severe axonal loss, who fail to improve post-treatment.

Paraneoplastic Limbic Encephalitis in a Human Epidermal Growth Factor Receptor-2-positive Gastric Cancer Patient Treated with Trastuzumab-combined Chemotherapy: A Case Report and Literature Review

Paraneoplastic neurological syndromes (PNSs) are rare nervous system dysfunctions in cancer patients, which are primarily observed with small-cell lung cancer, gynecological cancer, and thymoma. We herein present an uncommon case of PNS in an anti-Hu antibody-positive patient with human epidermal growth factor receptor (HER)-2-positive gastric cancer (GC), who developed limbic encephalitis and a worsening cognitive function. Trastuzumab-combined chemotherapy was initiated and appeared to be partially effective for controlling the neurological symptoms and tumor volume. Chemotherapy failure eventually led to uncontrollable neurological symptoms. This is the first case demonstrating that trastuzumab-combined chemotherapy may be effective for controlling neurological symptoms of PNS in HER2-positive GC patients.

[Autonomic neuropathy as the first presentation of T-cell malignant lymphoma--a case report]

A 61-year-old man noted flu-like symptoms. Not long afterwards, he felt constipation, nausea, and blackout when standing or sitting. His blood pressure was 110/70 mmHg in the supine position. On sitting blood pressure dropped to 73/34 mmHg. Heart rate increased from 65 to 78 beats per minutes. He did not have fever, edema, or skin rash. The remainder of the general medical examination was normal. A neurological examination revealed normal higher mental, and sensori-motor functions. The blood test revealed leukocytosis 7,320/μl, LD 1,426 IU/l, IL-2R 921 U/ml, and CRP 11.5 mg/dl. A whole body CT scan and cranial MR imaging showed no significant change. Thoracic spine MR imaging revealed multiple T1 low signal small foci in part of the vertebral body suggesting bone metastasis of the tumor. The heart/mediastinum ratio of (123)I-meta-iodobenzylguanidine scintigraphy early imaging was 2.42. The nerve conduction study and electrocardiogram coefficient of variation of R-R intervals showed no abnormalities. Two months after the onset of symptoms, he was found to have glove-and-stocking-form muscle weakness and sensory impairment. The nerve conduction study performed four months after the onset revealed a decreased conduction velocity and conduction block suggesting demyelinated nerve. His neurological manifestations progressed subacutely, despite high-dose intravenous immunoglobulin therapy. Five months after the onset, a histopathological diagnosis of T-cell malignant lymphoma was made on a skin biopsy specimen from the facial rash. To summarise, the present case was a rare example of paraneoplastic autonomic neuropathy as the initial clinical feature in association with T-cell malignant lymphoma.

Cranial neuropathies in granulomatosis with polyangiitis (Wegener's): a case-based review

The purpose of this case-based review is to highlight cranial nerve involvement in granulomatosis with polyangiitis (Wegener's). In this disease, cranial nerve involvement may be less frequent than other neurological manifestations, but often goes unrecognized by physicians as a sign of the disease, and its prevalence and importance is likely underestimated. Awareness of this aspect of the disease is necessary to make the proper diagnosis rapidly, as it can be a major feature of a patient's presentation. We also briefly discuss the known pathogenic mechanisms, which could be important when selecting the best therapeutic option.

Paraneoplastic neurological syndromes associated with gastric cancer: a case report and review of the literature

Paraneoplastic neurological syndromes (PNS) are associated with small-cell lung cancer, breast and gynecological cancers. We describe a gastric neoplasm presented with neurological symptoms. A 74-year-old male presented with tonic-clonic seizures. Initial investigations were normal; however, brain magnetic resonance imaging showed abnormal signal intensity in the hippocampi. A diagnosis of PNS was suspected. The patient was then diagnosed with a gastric neuroendocrine carcinoma with N-type voltage-gated calcium channel antibodies. The neurological impairments improved after the primary was resected and the patient remains free of cancer and paraneoplastic syndrome. We reviewed 10 cases of PNS associated with gastric cancer and found several characteristics: (1) older men, (2) neuroendocrine component or predominance, (3) oncological outcome for patients with PNS is better than for patients without PNS, and (4) neurological impairment is diagnosed 6 months prior to the diagnosis of gastric malignancy. In conclusion, elderly men with symptoms suggestive of PNS should be investigated for a gastric neuroendocrine malignancy.

Neuromuscular complications

Although direct neoplastic involvement of muscle tis-sue is surprisingly rare, considering the large amount of body mass that is represented by muscle tissue, the most important and unresolved muscle effect is muscle cachexia.Other associations, such as inflammatory, paraneo-plastic, toxic, and several extremely rare associations,have been described. Drug-induced toxicity and radiation recall syndrome need to be taken into consideration when muscle symptoms appear in patients with cancer.

A female with progressive four-limb paresthesias and gait difficulty

EDUCATIONAL OBJECTIVES

To discuss a case of progressive four-limb paresthesias and gait difficulty in a female who had previously undergone gastric bypass surgery.

KEY QUESTIONS

1) What is the differential diagnosis of progressive four-limb paresthesias and gait difficulty? 2) How would one approach diagnostic testing for such a patient? 3) What are the complications of gastric bypass surgery? 4) What is the treatment for this patient?

Paraneoplastic neurological syndrome in a patient with gastric cancer

Paraneoplastic neurological syndromes (PNSs) are a heterogeneous group of neurological disorders caused by immune-mediated mechanisms. The incidence of PNS is much less than 1% for solid tumors, except for small-cell lung cancer and thymoma. We report a rare case of gastric cancer that presented with primary clinical findings of PNS. The patient was a 63-year-old woman who was admitted for worsening neuropathy. Laboratory and neurological tests excluded a nutritional deficit, diabetes mellitus, and connective tissue disease as causes of her neuropathy. Computed tomography (CT) of the abdomen, positron emission tomography (PET)-CT, and endoscopy of the stomach revealed gastric cancer with lymph node swelling. Distal gastrectomy was performed and pathological and immunohistochemical examinations indicated endocrine cell carcinoma. The gastrectomy stopped the exacerbation of her symptoms and recurrence was not observed, but the neurological disorders were irreversible. This case suggests that early diagnosis of the primary tumor is required to improve the outcome in patients with PNS.

Mechanisms underlying autoimmune synaptic encephalitis leading to disorders of memory, behavior and cognition: insights from molecular, cellular and synaptic studies

Recently, several novel, potentially lethal and treatment-responsive syndromes that affect hippocampal and cortical function have been shown to be associated with auto-antibodies against synaptic antigens, notably glutamate or GABA-B receptors. Patients with these auto-antibodies, sometimes associated with teratomas and other neoplasms, present with psychiatric symptoms, seizures, memory deficits and decreased levels of consciousness. These symptoms often improve dramatically after immunotherapy or tumor resection. Here we review studies of the cellular and synaptic effects of these antibodies in hippocampal neurons in vitro and preliminary work in rodent models. Our work suggests that patient antibodies lead to rapid and reversible removal of neurotransmitter receptors from synaptic sites, leading to changes in synaptic and circuit function that in turn are likely to lead to behavioral deficits. We also discuss several of the many questions raised by these and related disorders. Determining the mechanisms underlying these novel anti-neurotransmitter receptor encephalopathies will provide insights into the cellular and synaptic bases of the memory and cognitive deficits that are hallmarks of these disorders, and potentially suggest avenues for therapeutic intervention.

Pathogenesis and treatment of paraneoplastic neurologic syndrome

Paraneoplastic neurologic syndrome, a rare complication of carcinoma, includes various neurologic disorders, such as encephalomyelitis, paraneoplastic cerebellar degeneration, subacute sensory neuronopathy, retinal paraneoplastic syndrome, opsoclonus-myoclonus syndrome and stiff-person syndrome. Several antibodies to malignant tumor cells and neurons are detected in sera and cerebrospinal fluids of patients with this syndrome, however, there is no direct evidence of antiYo or antiHu antibodies' causative roles in neuronal loss. Recent studies showed cytotoxic T-cell activities against peptides of an antigen protein recognized by antibodies in the peripheral blood of patients with paraneoplastic cerebellar degeneration and antiYo antibodies, as well as in patients with antiHu syndrome. Treatment of paraneoplastic neurologic syndrome with plasmapheresis, immunosuppresive drugs, or intravenous immunoglobulin therapy has been attempted. Here, we discuss previous reports and theoretical treatments based on recent etiological hypothesis of paraneoplastic cerebellar degeneration.

Painful peripheral neuropathies

Peripheral neuropathies are a heterogeneous group of diseases affecting peripheral nerves. The causes are multiple: hereditary, metabolic, infectious, inflammatory, toxic, traumatic. The temporal profile includes acute, subacute and chronic conditions. The majority of peripheral neuropathies cause mainly muscle weakness and sensory loss, positive sensory symptoms and sometimes pain. When pain is present, however, it is usually extremely intense and among the most disabling symptoms for the patients. In addition, the neurological origin of the pain is often missed and patients receive inadequate or delayed specific treatment. Independently of the disease causing the peripheral nerve injury, pain originating from axonal pathology or ganglionopathy privileges neuropathies affecting smaller fibres, a clinical observation that points towards abnormal activity within nociceptive afferents as a main generator of pain. Natural activation of blood vessels or perineurial nociceptive network by pathology also causes intense pain. Pain of this kind, i.e. nerve trunk pain, is among the heralding symptoms of inflammatory or ischemic mononeuropathy and for its intensity represents itself a medical emergency. Neuropathic pain quality rekindles the psychophysical experience of peripheral nerves intraneural microstimulation i.e. a combination of large and small fibres sensation temporally distorted compared to physiological perception evoked by natural stimuli. Pins and needles, burning, cramping mixed with numbness, and tingling are the wording most used by patients. Nociceptive pain instead is most often described as aching, deep and dull. Good command of peripheral nerve anatomy and pathophysiology allows timely recognition of the different pain components and targeted treatment, selected according to intensity, type and temporal profile of the pain.

Cancer-Induced, Immune-Mediated Ocular Degenerations

The means whereby vision can be lost from a disease located distant from the eye include autoimmunity, with sensitization resulting from extraocular stimuli, a process illustrated here by the immunologic confusion caused by cancers. The uncontrolled proliferation of malignancies commonly involves the expression of components of the central nervous system, but a damaging loss of tolerance is rare. When autoimmunity does develop, organ-specific antigens are more often involved than the more generalized and widely disseminated common neuronal components. A focus upon a single antigen is typical of the immune-mediated paraneoplasia, a collection of syndromes identified by unusual antibody reactions. This review provides an outline of the immunologic trail that led to the recognition of autoimmunity in paraneoplastic ocular degenerations, how specific antibody reactions aid in diagnosis, and the possibility of including antibodies in modes for sight-saving intervention. 'Those who do not know history are destined to repeat it'.

Steroid-responsive paraneoplastic demyelinating neuropathy and myelopathy associated with breast carcinoma

Paraneoplastic myeloneuropathy has rarely been reported with breast cancer. We report the case of a 59-year-old woman who presented with a peripheral neuropathy and cranial involvement and later developed a myelopathy. The neuropathy was found to be electrophysiologically and histologically demyelinating in nature. Magnetic resonance imaging studies failed to identify any structural brain or spinal cord abnormalities. The patient was diagnosed with breast carcinoma 4 months after initial presentation and underwent resective surgery, radiotherapy, and hormonotherapy. Paraneoplastic antibodies (anti-Hu, anti-Yo, anti-Ri, anti-CV2, anti-Ma, and anti-amphiphysin) were all negative. Her condition did not progress further after cancer treatment. Partial neurologic improvement occurred with oral steroid therapy, with subsequent deterioration on treatment withdrawal.

Paraneoplastic syndromes of the CNS

Major advances in the management of paraneoplastic neurologic disorders (PND) include the detection of new antineuronal antibodies, the improved characterisation of known syndromes, the discovery of new syndromes, and the use of CT and PET to reveal the associated tumours at an early stage. In addition, the definition of useful clinical criteria has facilitated the early recognition and treatment of these disorders. In this article, we review some classic concepts about PND and recent clinical and immunological developments, focusing on paraneoplastic cerebellar degeneration, opsoclonus-myoclonus, and encephalitides affecting the limbic system.

Paraneoplastic neurological syndromes and onconeural antibodies: clinical and immunological aspects

Paraneoplastic neurological syndromes (PNS) are infrequent disorders that are associated with cancer. The syndromes are highly heterogeneous and often affect several areas of the nervous system. Among the most well-known syndromes are paraneoplastic encephalomyelitis, cerebellar degeneration, sensory neuronopathy, and Lambert-Eaton myastenic syndrome. There are various associated tumors, in particular small cell lung cancer, cancer of the breast and ovary, and thymoma. The onset of neurological symptoms often precedes the cancer diagnosis, and the recognition of a paraneoplastic syndrome should lead to immediate search for cancer. The etiology of the paraneoplastic syndromes is believed to be autoimmune. Antibodies to onconeural antigens, expressed in the tumor of the affected individual and in normal neurons, are found in many of the patients. These antibodies are useful markers for paraneoplastic etiology. The pathogenesis of the PNS is uncertain, but cellular immune responses are thought to be the main effector mechanism. The cornerstone of therapy is the identification and treatment of the underlying malignancy. In some of the disorders, immunosuppressive therapy is of additional benefit. The prognosis of the different PNS varies depending on the level of affection and the degree of neuronal death.

Peripheral nervous system involvement in patients with cancer

Involvement of the peripheral nervous system (PNS) is common in patients with cancer and any part, including motor neurons, sensory ganglia, nerve roots, plexuses, cranial and peripheral nerves, and neuromuscular junctions, can be affected. Different mechanisms can initiate damage associated with cancer-related PNS disorders. These include tumour infiltration, toxicity of treatments, metabolic and nutritional perturbations, cachexia, virus infections, and paraneoplastic neurological syndromes. The type of cancer, lymphoma, or solid tumour is a further determinant of a PNS disorder. In this Review we discuss the different causes and mechanisms of disorders of the PNS in patients with cancer and we will focus on their assessment and diagnosis.

A Diagnostic and Management Dilemma

BACKGROUND

Neuromuscular junction disorders are usually categorized as either presynaptic or postsynaptic. The most frequently encountered disorder of the postsynaptic neuromuscular junction is acquired myasthenia gravis. Lambert-Eaton myasthenic syndrome is a well-known prototype of the presynaptic autoimmune disorders of neuromuscular transmission. These major disorders of neuromuscular transmission are relatively common and distinctly recognized, but co-occurrence of these disorders (overlap myasthenic syndrome) is rare and has so far attracted little attention.

REVIEW SUMMARY

This report describes a patient with acquired myasthenia gravis and immunologic coexistence of Lambert-Eaton myasthenic syndrome (overlap myasthenic syndrome) in association with abdominal/uterine leiomyosarcoma. The patient presented with acute respiratory failure, making identification and management of her illness challenging. A general overview of the complexities associated with overlap between myasthenia gravis and Lambert-Eaton myasthenic syndrome is provided and this patient's complicated clinical course and response to therapy are discussed.

CONCLUSION

To our knowledge, this is the first report of overlap myasthenic syndrome in conjunction with abdominal leiomyosarcoma. The immunologic coexistence of acquired myasthenia gravis and Lambert-Eaton myasthenic syndrome in a patient with a malignant smooth-muscle tumor is intriguing and suggests that a common paraneoplastic process targeting 2 different onconeural antigens was the underlying pathogenic mechanism in this patient.

Acute motor and sensory axonal neuropathy in Burkitt-like lymphoma

Immune-mediated neuropathies associated with non-Hodgkin's lymphoma are rare and can be difficult to delineate from neuropathies of other etiologies. We report the clinical and pathological findings of a 36-year-old patient with fulminant quadriplegic neuropathy, left facial nerve palsy, and Burkitt-like lymphoma. Features of the neuropathy, which occurred during induction chemotherapy with a total cumulative dose of 4 mg vincristine, suggested axonal Guillain-Barré syndrome. There was no evidence of direct malignant infiltration of the peripheral nervous system. We hypothesize that immune mechanisms triggered by the lymphoma initiated damage to the peripheral nervous system and enhanced its vulnerability to the toxic effects of vincristine.

Rhabdomyolysis and paraneoplastic stiff-man syndrome with amphiphysin autoimmunity

Stiff-Man syndrome (SMS) is a rare disease of the central nervous system characterized by chronic muscle rigidity and autoimmunity directed against synaptic antigens. In a subset of patients, generally positive for antiamphiphysin autoantibodies, SMS has an autoimmune paraneoplastic origin. Amphiphysin isoforms are expressed at high levels in brain and skeletal muscle and often are overexpressed in breast cancer. We report here the occurrence of rhabdomyolysis in a patient with SMS, breast cancer, and antibodies that recognize both brain and muscle amphiphysin isoforms. Immunotherapy induced a remission of both rhabdomyolysis and SMS symptoms. Autoimmune rhabdomyolysis may represent a paraneoplastic complication of cancer patients with amphiphysin autoimmunity.

Neurologic paraneoplastic syndromes

Paraneoplastic disorders can affect any part of the central or peripheral nervous system. Although relatively uncommon, these disorders are a significant cause of severe neurologic disability among cancer patients. Many paraneoplastic disorders are believed to be caused by an autoimmune response directed against shared neural tumor antigens. This article summarizes the clinical features, possible autoimmune pathophysiology, and management issues for patients with paraneoplastic disorders.

Neuromuscular symptoms in cancer patients

The neuromuscular system is often affected in patients with cancer. This can be due to a direct effect of cancer, neurotoxic treatment, radiation therapy or paraneoplastic phenomena. This review focuses on the sites of involvement, such as cranial nerves, nerve roots, and plexus, mono- and polyneuropathies disorders at neuromuscular transmission, and muscle disease. At each site of the peripheral nervous system, the most common types of involvement and therapeutic issues are discussed. Knowledge of neuromuscular symptoms is important for medical oncologists, neurologists and neuro-oncologist alike, as precise diagnosis may have therapeutic consequences for the patients. Immunologic therapies, or in some cases anticancer treatment may decrease the individual's burden of disease in paraneoplastic syndromes. Conventional cancer therapies, such as chemotherapy and radiation therapy, also have neurotoxic side effects which need to be outweighed against their therapeutic effect. Several other less well-defined complications such as infection, hemorrhage or metabolic disorders have to be considered as a differential diagnosis. Complications of surgical and other interventions will not be discussed in this context.

Paraneoplastic neurologic syndromes

Cancer can affect the nervous system through many metastatic and nonmetastatic mechanisms, including side effects of cancer treatment, infections, coagulopathy, and metabolic or nutritional deficits. Paraneoplastic neurologic disorders (PND) are an extensive group of syndromes that cannot be explained by any of these complications and may affect any part of the nervous system. PND often develop before the presence of a cancer is known and their recognition may lead to the tumor diagnosis.