Macroangiopathy is a positive predictive factor for response to immunotherapy

Zielsetzung:

Introduction of immunotherapies demands for predictive imaging biomarkers to avoid unnecessary adverse effects and costs. In this study we investigated different body composition measures including the vascular system as well as muscle and adipose tissue parameters for their ability to serve as surrogates of immune status and to predict response to immunotherapy.

Material und Methoden:

This retrospective analysis was approved by the institutional ethics committee and encompassed abdominal portal-venous CT scans and cerebral fluid-attenuated inversion-recovery MRI (FLAIR) of 147 patients close to immunotherapy with ipilimumab. Total plaques index (TPI) defined as body height corrected sum of soft and hard plaque volume of the abdominal aorta, mean psoas density (MPD), total psoas area (TPA) as well as different adipose tissue parameters were extracted from CT data. Cranial FLAIR was used to quantify deep white matter hyperintensities (dWMH) by applying the Fazekas Scoring System (FS) and body weight, body mass index (BMI), and progression free survival (PFS) were determined by chart review.

Ergebnisse:

TPI and MPD were significantly associated with PFS both in univariate as well as multivariate cox regression analysis with adjustment for age and number of received immunotherapy cycles (p = 0.03 (HR = 0.89) and p = 0.002 (HR = 0.96)). None of the adipose tissue parameters nor degree of dWMHs, age or number of immunotherapy cycles correlated with PFS.

Schlussfolgerungen:

Degree of macroangiopahty and sarcopenia predict response to ipilimumab therapy, which might be exploited as imaging biomarkers for outcome to immunotherapy.