Paraneoplastic myopathy: response to intravenous immunoglobulin

Necrotizing autoimmune myopathy

“…Paraneoplastic necrotizing myopathy is rarely described in the literature, but is known to be associated with a range of cancers including gastrointestinal adenocarcinoma (also pancreatic, gallbladder), small cell and nonsmall cell lung, breast, prostate, and transitional cell cancers [9,21,28 ], and myeloma [29]. Again the histological appearance and response to immunotherapy point to humoral or cytokine-mediated myocyte injury [21,29].…”

“…Again the histological appearance and response to immunotherapy point to humoral or cytokine-mediated myocyte injury [21,29]. Unlike cancer-associated myositis related to dermatomyositis where specific antibodies have been identified [19], only a few cases have been reported of a necrotizing paraneoplastic myositis being associated with an antibody: one with a muscle-specific autoantibody in a patient with colon cancer [30] and another in a patient with large-cell lung cancer, in whom the anti-SRP antibody was also found [29].…”

“…MAC deposition may be seen on small blood vessels, which is more prominent in anti-SRP-associated NAM than in paraneoplastic-associated myopathies [3,28 ]. Pipestem Necrotizing autoimmune myopathy Liang and Needham 615 Clinical -all-subacute onset symm-etrical proximal weakness Dysphagia [32 ,33] Myalgia [24] Dysphagia Severe muscle atrophy [33] Dysphagia [22 ] Facial weakness [21,29] Onset in autumn-winter Respiratory involvement [28 ] Weight-loss [3] Rash [29] Cardiac complications [16] Myopathy not always parallel tumor progression Interstitial lung disease [33] Alkaline phosphatise staining in regenerating fibres/ perimysial connective tissue [21] Response to immunetherapy…”

Paraneoplastic necrotizing myopathy in association with metastatic malignant melanoma: two case reports and a review of the literature

“…Additional treatment with intravenous immunoglobulins, monoclonal antibodies, and immune modulators may also be beneficial to some patients [10] . Interestingly, treatment responses vary among patients, and the severity of the condition does not always parallel tumor progression [20] . Necrotizing myopathy has been reported to be responsive to treatment when the tumor is controlled [18] .…”

Long-Term Outcome of Polymyositis Treated with High Single-Dose Alternate-Day Prednisolone Therapy

“…Patients showing rimmed vacuoles and intracellular amyloid deposits on pathological examination (possible inclusion body myositis), and others showing characteristic clinical features, such as finger flexor, wrist flexor, and quadriceps muscle weakness [4,5], were excluded. Patients with myopathy associated with anti-signal recognition particle antibodies that have usually shown active necrosis and little or no inflammation [6,7,8], statin-induced myopathy that shows features suggestive of mitochondrial dysfunction [9,10], and paraneoplastic necrotizing myopathy that exhibits numerous necrotic fibers but little inflammation [11,12] were also excluded. We also excluded patients who did not show electromyography findings compatible with inflammatory myopathy; that is increased insertional activity, fibrillation potentials, and positive sharp waves, in addition to polyphasic motor unit potentials of low amplitude and short duration.…”