Inclusion body myositis and transitional cell carcinoma of the bladder: significant resolution of symptoms after tumor excision.

Inclusion body myositis (IBM) is a separate class of the inflammatory myopathies with recently proposed clinical and pathological diagnostic criteria. An association between inflammatory myopathies and malignancy has been questioned in the literature. Recent reviews of the inflammatory myopathies suggest that only dermatomyositis is associated with malignancy. The largest study to date of patients with IBM found that 15% had a malignancy (6 of 40). We report the first documented case of IBM and concurrent transitional cell carcinoma of the bladder. We suggest that a causal relationship between IBM and malignancy may exist because of significantly improved functional strength gained after tumor removal.