Paraneoplastic rheumatic syndromes.
Malignant neoplasms are associated with a wide variety of paraneoplastic rheumatological syndromes. Among these, hypertrophic osteoarthropathy, carcinoma polyarthritis, dermatomyositis/polymyositis, and paraneoplastic vasculitis are the most frequently recognized. Other less known associations are based upon a smaller number of reported patients, and include fasciitis, panniculitis, erythema nodosum, Raynaud's syndrome, digital gangrene, erythromelalgia and lupus-like syndromes. Musculoskeletal manifestations of malignancy may coincide, follow or antedate the diagnosis of cancer, or herald its recurrence. The clinical course generally parallels that of the primary tumour, and treatment of the underlying malignancy often results in regression of the rheumatic disorder. Awareness that cancer can cause certain non-metastatic symptoms is important for early diagnosis and treatment of an occult neoplasm. Rheumatic manifestations suggesting a hidden cancer include: rapid onset of an unusual inflammatory arthritis clubbing or diffuse bone pains in a patient 50 years of age or older, chronic unexplained vasculitis, refractory fasciitis, Raynaud's syndrome unresponsive to vasodilator therapy, rapidly progressive digital gangrene or Lambert-Eaton myasthenic syndrome. Management consists of control of the underlying cancer and symptomatic treatment of the rheumatic syndrome with non-steroidal anti-inflammatory drugs or corticosteroids.