[Muscle pain in myositis in a young female patient: what is behind this?]

Myositis is a connective tissue disease which is most frequently diagnosed in women aged 40-60 years. Due to a clear association with underlying malignant diseases, general tumor screening is recommended whenever it is diagnosed. Colorectal carcinoma (CRC) is a common malignant disease, and the typical at-risk group comprised, to date, patients older than 55 years. However, with the rising incidence of so-called early-onset colorectal carcinoma (EO-CRC), an increasingly important patient population is emerging in the 20- to 50-year age range. One reason for the rising incidence is suggested to be an increase in classic risk factors at younger ages. Here, the case of a 34-year-old female patient who presented with the leading paraneoplastic syndrome of myositis and was diagnosed with a sporadic form of CRC is reported. Monitoring of known risk factors as early on as in young adulthood and greater attention in the presence of symptoms such as gastrointestinal hemorrhage or paraneoplastic syndromes seem necessary to compensate for the time delay in diagnosis that currently still exists and the associated worse oncologic outcome.