Survivorship in Immune Therapy: Assessing Chronic Immune Toxicities, Health Outcomes, and Functional Status among Long-term Ipilimumab Survivors at a Single Referral Center

Ipilimumab, a novel immune checkpoint inhibitor, is associated with long-term survival in approximately 20% of patients with advanced melanoma and is also being evaluated in the adjuvant setting. With this growing cohort of survivors, long-term health outcomes, chronic toxicities, and functional outcomes among survivors treated with ipilimumab need to be defined. Using retrospective medical record abstraction, we evaluated disease status, chronic immune- and non-immune-related health events, pharmacologic management of symptoms, and functional status in patients with melanoma, with overall survival >= 2 years following ipilimumab treatment at Vanderbilt University. Ninety patients received ipilimumab for metastatic disease or as adjuvant therapy between January 2006 and September 2012, and 33 patients survived >= 2 years, with a median overall survival of 60.1 months. Of these, 24 patients were alive at the last follow-up (73%), with 14 patients free of disease (42%). Gastrointestinal and dermatologic adverse events were frequent but largely transient. By contrast, patients with hypophysitis universally required ongoing corticosteroids, although largely remained asymptomatic with appropriate hormone replacement. Surviving patients generally had excellent performance status (ECOG 0-1 in 23 of 24). Chronic neurologic toxicities caused substantial morbidity and mortality in 2 patients who received whole-brain radiotherapy >5 years before analysis, and in one patient with chronic, painful peripheral neuropathy. No previously undescribed cardiac, pulmonary, gastrointestinal, hematologic, or neoplastic safety signals were identified. In conclusion, ipilimumab was associated with largely excellent functional outcomes among long-term survivors. Chronic endocrine dysfunction and occasional neurologic toxicity (primarily associated with whole-brain radiation) were observed in a small number of patients.