Mamtani R, Clark AS, Scott FI, Brensinger CM, Boursi B, Chen L, Xie F, Yun H, Osterman MT, Curtis JR, Lewis JD. Association Between Breast Cancer Recurrence and Immunosuppression in Rheumatoid Arthritis and Inflammatory Bowel Disease: A Cohort Study. Arthritis Rheumatol. 2016 10; 68(10):2403-11.