Increased Cancer Risk with Autoimmune Disorders Save

The incidence and mortality of cancer among autoimmune diseases (AID) was studied in a large Chinese cohort, demonstrating that while onset time and risks vary, there is an increased risk of malignancy in AID.

The cohort included 8,120 AID patients from a national tertiary referral center with a follow-up of 38,726.55 patient-years.  AID diagnsoes included patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren’s syndrome (SS), systemic scleroderma (SSc), and idiopathic inflammatory myositis (IIM). 

The observed a total of 430 cancers (5.3%). The standardized incidence ratio (SIR) of cancer in AIDs patients (compared to general population) was :

• Overall: 3.37
• Idiopathic inflammatory myositis: 4.31 (higher risk of ovarian cancer)
• RA: 3.99 (wide distribution of non-Hodgkin’s lymphoma, gynecologic, urinary tract, thyroid gland and lung cancers)
• Systemic Sclerosis: 3.77 (increased risk of cervical uterine, lung, and breast cancers)
• Sjogrens: 2.88 (most common  non-Hodgkin’s lymphoma)
• SLE: 2.58 (most common: hematologic malignancies; solid tumors in the urinary bladder, corpus uteri and cervix)

Cancers in AID patients were more likely in females (female vs. male: SIR 3.59 vs. 2.77) and younger patients (age <50 vs. ≥50 years: SIR 4.88 vs. 3.04).

Cancer screening is highly appropriate in these autoimmune disorders.