Colonic perforation: An unusual complication of therapy with high‐dose lnterleukin‐2

The majority (85%) of patients receiving high dose Interleukin‐2 (IL‐2) experience gastrointestinal side effects, namely nausea, vomiting and diarrhea. In this article we describe four cancer patients that developed localized necrosis or perforation of the colon during IL‐2 treatment. They represent 1.3% of patients (n = 315) or 0.9% of treatment courses (n = 452). All underwent surgical intervention and survived to leave the hospital. No common etiologic factor was apparent. Two patients were subsequently retreated with IL‐2 without complication. Localized colonic necrosis or perforation is a rare complication associated with high dose IL‐2 treatments. Aggressive surgical intervention is advocated and retreatment following recovery is safe.