Hyperprogressive disease in patients with recurrent high grade gliomas treated with immune checkpoint inhibitors or other therapies.

Abstract

e13575 Background: Hyperprogressive disease (HPD) has been described in solid tumor patients treated with immune checkpoint inhibitors (ICI). HPD is defined as a ≥2-fold increase in tumor growth rate (TGR) following initiation of ICI. HPD has not been explored in patients with high grade gliomas (HGG) on ICI or standard cytotoxic regimens. In advanced cancer patients receiving ICI, MDM2/4 amplification or EGFR alterations, both found in HGG, correlated with HPD. We compared the rate of HPD in recurrent HGG patients receiving ICIs to those treated with non-immunotherapy agents. Methods: Patients with HGG on ICIs for 1st or 2nd recurrence were compared to a control group receiving other therapies at 1st recurrence. Patients with prior or concurrent bevacizumab or anti-VEGFR were excluded due to pseudoresponse and decreased enhancement with these drugs. HPD was calculated by comparing TGR immediately before and after treatment. Results: 49 patients met inclusion criteria (27 ICI, 25 control). 25/27 patients treated with ICIs and 20/22 patients in the control group had complete imaging and were eligible for analysis. In the ICI group, 60% were men (15/25) and 88% (22/25) had a diagnosis of GBM. 68% were treated at first progression (17/25). Controls were 80% male (16/20) and all had a diagnosis of GBM. 30% (6/20) were 65 years or older at diagnosis in the control group compared to 28% (7/25) in the ICI group. In total, 7/25 patients met criteria for HPD in the ICI group (28%) compared to 4/20 patients in the control group (20%). 10/25 patients (5/7 with HPD) in the ICI group and 8/20 patients (2/4 with HPD) in the control group had next generation sequencing of their tumors. EGFR alterations and MDM2/4 amplifications were not associated with HPD whereas PTEN mutations were more common in the HPD group (71% HPD vs. 33.3% no HPD). Conclusions: HPD is observed in patients with HGG treated with ICI at comparable rates to those with other cancers, but was also observed in 20% of patients receiving other therapies. While the numbers are small, PTEN mutations may be associated with HPD in patients with HGG. In contrast to other solid tumors, EGFR alterations and MDM2/4 amplifications were not associated with HPD in HGG.