Rheumatological mimics of oncological disorders: a case report

Difficulties in diagnosing system lupus erythematosus аssociated with a diverse clinical picture where new signs of the disease appear throughout the disease, and a number of symptoms disappear. There are often cases of unusual onset of the disease with absence of skin manifestations asymptomatic course of the disease. Case summary. This article presents the history of a 37-year-old patient who had manifestations of systemic autoimmune disease with autoantibodies positivity in her debut, which led to an erroneous diagnosis and inadequate treatment. Discussion. The practice of a rheumatologist increasingly notes clinical cases requiring differential diagnosis between rheumatic diseases and paraneoplastic syndrome. "Rheumatological masks" can develop in malignant tumors of different localization at different stages of the disease, showing signs of damage to the bone-joint and ligament apparatus, muscles, vessels and internal organs. Keywords: systemic lupus erythematosus, lupus-like syndrome, paraneoplastic syndrome, differential diagnostics.