Is anti-TNF therapy safe for inflammatory bowel disease patients with prior cancer?

In patients with prior cancers whose IBD isn't controlled with other treatments, "Anti-TNF could be used taking into account a mild risk of incident cancer," according to the report by Dr. David Laharie of Centre Hospitalier Universitaire de Bordeaux, France, and colleagues.

The researchers analyzed a large IBD database to identify patients treated with anti-TNF agents who had a history of cancer within the past five years. Biological medicines directed against TNF can induce and maintain remission in patients with IBD: Crohn's disease or ulcerative colitis.

Patients with IBD and prior cancers often do not receive anti-TNF therapy, for fear that it will increase the risk of new or recurrent cancers. (There is no evidence that this treatment affects cancer risk in patients without a previous history of cancer.)

The study identified 79 adult patients with prior cancers who received anti-TNF therapy at 20 treatment centers. All patients had extensive prior treatment for their IBD, including anti-TNF therapy in one-half and major abdominal surgery in one-third. The most common types of cancer were breast and skin cancer. Anti-TNF treatment was started a median of 17 months after cancer diagnosis.

During a median follow-up of 21 months, 19 percent of the patients developed cancer. Eight had recurrence of their prior cancer while seven developed new cancers. Five of the new cancers were less-serious skin cancers called basal cell carcinomas. Five patients died, four of them as a result of recurrent cancer.

Ninety-six percent of patients were alive and cancer-free one year's follow-up, 86 percent at two years, and 66 percent at five years. The overall incidence of recurrent or new cancers was about 85 per 1,000 patient-years. (In other words, if 1,000 patients were followed up for one year, 85 would develop cancer.)

Another type of IBD medication (thiopurines) has been linked to an increased risk of basal cell carcinoma and other non-melanoma skin cancers. On analysis excluding patients with these less-serious skin cancers, the incidence of cancer decreased to about 67 per 1,000 patient-years.

The study is one of the first to assess cancer risk associated with anti-TNF therapy in IBD patients with prior cancer. Dr. Laharie and coauthors note that their study included a "highly selected" group of patients--all of whom had uncontrolled IBD that prompted their physicians to start anti-TNF therapy, despite their history of cancer. With advances in treatment over the past two decades, doctors are seeing more IBD patients with previous or current cancer, with earlier and longer use of anti-TNF and other "immunmodulatory" treatments.

In deciding whether to use anti-TNF in this group of patients, physicians must balance the potential increased cancer risk against the need to get the patient's IBD under control, Dr. Laharie and colleagues believe. "Pending additional data," they write, "it should be a case-by-case decision taken with the oncologist and the patient, taking into account natural history of cancer according to location, histological type, time since cancer diagnosis and IBD prognosis."