Objective: We aimed to study the risk of renal cell carcinoma (RCC) with anti-tumor necrosis factor (anti-TNF) therapy in inflammatory bowel disease (IBD) and rheumatic diseases (RD) and calculate standardized incidence ratios (SIRs) in IBD.
Materials and methods: This was a retrospective case-control and cohort study spanning 25 years, including IBD and RD patients with a diagnosis of RCC (1990-2014) identified through the electronic database of a tertiary referral center.
Results: RCC was confirmed in seven anti-TNF-exposed (TNF+) and 21 anti-TNF-naive (TNF-) IBD and one TNF+ and 26 TNF- RD patients. In IBD-RCC, younger age at RCC diagnosis [median (interquartile range) 46 (42-58) vs. 63 (52-75) years; P=0.02], immunosuppressive therapy (100 vs. 24%; P<0.0004), partial nephrectomy (86 vs. 33%; P=0.02), and surgery less than 1 month after diagnosis of RCC (71 vs. 14%; P=0.004) were associated with anti-TNF. Compared with IBD, RD patients were older at RCC diagnosis [70 (60-77) vs. 59 (47-69) years; P=0.02] with less nephron-sparing surgery (26 vs. 54%; P=0.04) and more symptomatic (44 vs. 14%; P=0.02) and advanced tumors (30 vs. 7%; P=0.04). SIRs in IBD-RCC TNF- and TNF+ were 5.4 (95% confidence interval 2.9-9.2) and 7.1 (2.3-16.5) in male patients and 8.5 (3.7-16.8) and 4.8 (0.6-17.3) in female patients, respectively. The risk for RCC associated with anti-TNF in IBD was 0.8 (0.3-2.5) in men and 1.4 (0.2-5.5) in women.
Conclusion: The favorable patient and tumor profiles in IBD with anti-TNF may suggest incidentally discovered RCC on abdominal imaging. SIRs for IBD-RCC were not increased after anti-TNF exposure.