Grant: Operating Grant

Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA) are both serious diseases caused by an overactive immune system, resulting in inflammation and damage. SLE can occur at any age; 15-20% of cases may present in childhood, often with more severe disease than adults. Similarly, RA is an serious type of arthritis in adults, with Juvenile Idiopathic Arthritis (JIA) being the currently-used term for a similar arthritis that arises in childhood. Fortunately, survival in pediatric rheumatic diseases has improved in the past two decades. This means that preventing adverse events is of increasing importance not only to clinicians, but also to patients and their families. Important types of adverse events may include osteoporosis, cardiovascular disease-and potentially, cancers. Several large studies, many of them population-based, have studied cancer risk in adults with RA and SLE. These studies have all emphasized a consistent and clinically important increased risk for lymphoma. Though much has been learnt about cancer risk for adults with rheumatic diseases, there are essentially no data about their pediatric counterparts. Despite lack of evidence, patients with pediatric-onset SLE and JIA, and their families, still fear that they too are at high risk for cancer. Our study will provide new information with a long-term study in pediatric-onset SLE and JIA. We will examine cancer occurrence in two multi-center cohorts, one with SLE and one with JIA, and determine if cancer risk is increased compared to age-and-sex specific general population cancer incidence rates. What is learnt from our work will certainly advance knowledge about cancer risk, particularly in high-risk populations.