TNF inhibitors may not increase cancer recurrence risk
medwireNews: Patients with a history of cancer who receive tumor necrosis factor (TNF) inhibitors for rheumatoid arthritis (RA) may not be at increased risk for recurrence, suggests a Swedish population-based study.
The researchers point out, however, that the confidence intervals of several of the risk estimates had an upper limit of 2 or more, therefore “a clinically meaningful risk cannot be completely ruled out.”
Using data from various national and population-based registers, the team identified 467 patients with a history of solid cancer and RA who started TNF inhibitor therapy between 2001 and 2015, at a median of 7.9 years after the cancer diagnosis. These patients were matched by several factors – including sex, age at cancer diagnosis, and year of cancer diagnosis – to 2164 controls with prior cancer who did not receive TNF inhibitors for RA. All individuals had to be in remission for at least 6 months.
Over an average follow-up of 5.3 years 9.0% of TNF inhibitor-treated patients experienced cancer recurrence, as did 7.2% of biologic-naïve controls during a mean of 4.3 years, giving a nonsignificant adjusted hazard ratio (HR) of 1.06.
Pauline Raaschou (Karolinska Institutet, Stockholm, Sweden) and the ARTIS Study Group investigators also limited the sample to individuals whose cancer was diagnosed in 2001 or later, which reduced the median time from cancer diagnosis to TNF inhibitor therapy to around 4.5 years. The findings were similar to those of the overall analysis, with cancer recurring in 10.0% of patients who received TNF inhibitors and 7.3% of those who did not (adjusted HR=1.08).
The HRs obtained in sensitivity analyses that adjusted for the remission interval (3 or 12 months) and cancer stage were also not “appreciably” different to those of the main analysis, report the study authors in the Annals of Internal Medicine.
Altogether, these results suggest that TNF inhibitors are “not associated with increased risk for cancer recurrence in patients with RA,” they summarize.
But Raaschou et al admit that the study participants were prescribed TNF inhibitor therapy “at a time when most clinical guidelines [cautioned] against its use in patients with a history of cancer.”
They continue: “Thus, the TNF [inhibitor]-treated participants may have had an inherently lower risk for recurrent cancer (reflected by a longer time since the index cancer or more favorable tumor characteristics) than those who did not receive TNF [inhibitors].”
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group