Predictive factors of toxicity of immune checkpoint inhibitors (ICI) in older patients with lung cancer: The ToxImmune study.

Abstract

12048 Background: Immunotherapy (Im) improved the survival of patients with lung cancer. It may be responsible for adverse events impacting these patients' quality of life. We have few data on the tolerance of older cancer patients (OP) to immunotherapy. The Toximmune study aims to describe the safety of older lung cancer patients to Im and identify clinical, biological and radiological markers that can help to predict immune-related adverse events for OP. Methods: All patients aged 60 years and older who had received at least one dose of ICI between June 2015 and December 2020 and diagnosed with lung cancer were included. We collected patients' baseline demographic characteristics, biological blood markers and imaging by PET-scanner. All adverse events (AEs) and immune-related AEs (irAEs) were recorded (CTCAE V.5.0). Results: 49 patients were included, median age was 71 (range 61-97). The incidence of grade 2 and grade 3-4 was 34% and 6% respectively. The main irAEs reported were: asthenia in 51% patients after 13.5 months median delay (grade ≥2 in 22%),musculoskeletal disorders in 45% after 21 months median delay (grade ≥2 in 10%), pneumonitis in 37% after 21 months median delay (grade ≥2 in 10%), and colitis in 35% after 21 months median delay (grade ≥2 in 6%). Female sex, primitive tumor SUV max < 5, number of metastases ≥ 3, prior systemic therapy > 1, PLR < 250 were significantly associated with a risk of toxicity in univariate analysis (p < 0.05) We developed the ToxImmune score (0, 1, or ≥2) to predict the risk of having a grade ≥2 adverse event by adding the following risk factors: Primitive Tumor SUV < 5 = 1, Number of metastases ≥3 = 1, And L1 = 0 vs > L1 = 1. The incidence of grade ≥2 adverse events was 31%, 35% and 86% with ToxImmune scores 0, 1 and 2 respectively (p = 0.032). Median overall survival times (OS) & progression-free survival (PFS) were 21.8 & 21 months, 15.1 & 6.6 months, and 9.8 & 2.1 months for ToxImmune scores 0, 1 and ≥ 2 respectively (p = 0.06 & p = 0.001). There was significant association between the ToxImmune score and the risk of "progressive disease" at the first assessment of the disease: 16% for score = 0, 48% for score = 1, and 71% for score = 2, (p = 0.01). Conclusions: The quality of life is our goal for OP care. The ToxImmune score, which is based on objective clinical parameters, identifies OP with a significant higher risk of severe adverse events. Also, this score was significantly associated with patients’ PFS risk of developing rapid tumor progression. It could be used in clinical practice to personalize toxicity surveillance in OP treated for lung cancer with immunotherapy. This score will be validated in larger prospective cohorts.