Tumor necrosis factor (TNF) inhibitors are used worldwide to reduce inflammation and stop disease progression in adults and children with inflammatory conditions like rheumatoid arthritis, psoriatic arthritis, juvenile arthritis, inflammatory bowel disease, and psoriasis. A new study cautions that pediatric patients receiving these drugs be screened for cancer long-term, especially for unusual neoplasms.
The study, published in Pediatric Rheumatology, identified rare solid tumors in six young patients at a single facility who were being treated with TNF inhibitors – either etanercept (Enbrel) or infliximab (Remicade). One patient developed Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma, a rare type of head and neck cancer. Two young patients developed renal clear cell carcinoma.
Both diseases are “extremely rare” in young patients, the researchers said. The incidence of patients younger than 21 diagnosed with renal clear cell carcinoma is 0.01 per 10,000. The incidence of nasopharyngeal carcinoma in children and adolescents in North America is about 0.5 per million person years.
In 2010, the Food and Drug Administration (FDA) announced in a Safety Communication that it had received 48 reports of malignancy among children who were being treated with TNF inhibitors. However, the authors said that a clear, casual relationship could not be established because of various factors including the underlying disease itself. Other studies have found a higher rate of malignancies in pediatric patients taking anti-TNF therapies.
The overall malignancy rate was 1.68 percent among the 357 children studied. Diagnosis occurred at a median of five years from starting the drugs. Three of the six patients diagnosed with the rare cancer were treated with infliximab, one patient was treated with etanercept, and two were receiving both drugs. All six patients were also being treated with the first-line treatment methotrexate.
Source: Medpage Today