1480P - Integrating the on-treatment mGPS improves prognostic accuracy of imaging-based staging in patients with non-small-cell lung cancer (NSCLC) treated with immune-checkpoint inhibitors

Background

The clinical standard for response evaluation and treatment monitoring in advanced non-small cell lung cancer (NSCLC) is repeated, imaging-based staging. However, on immune checkpoint inhibition (ICI), many patients achieve stable disease (SD) as the best overall response. Clinical outcomes in this group vary widely, and whether measuring tumor size adequately captures the complex, dynamic processes following immune checkpoint inhibition is controversial. Hence, complementary biomarkers that improve outcome prediction are needed. A promising candidate is the modified Glasgow prognostic score (mGPS), a well-established prognostic score based on the serum markers C-reactive protein (CRP) and albumin that has demonstrated to predict clinical outcomes in a variety of oncological settings.

Methods

We re-evaluated the mGPS at the time of first staging (6 weeks after the start of therapy) in patients with NSCLC treated with atezolizumab (anti-PD-L1 antibody) in the phase 3 OAK trial.

Results

In patients treated with anti PD-L1 (n = 412), the on-treatment mGPS yields prognostic information similar to radiological staging (c-index 0.65 (95 % confidence interval 0.61 – 0.68) vs 0.61 (0.57 - 0.64). Notably, the mGPS low-risk subgroup is larger (54.4 %) compared to the partial response (PR) subgroup (7,5%). In the clinically heterogenous SD subgroup, on-treatment mGPS strongly correlated with survival (intermediate risk HR 2.4, p < 0.001, high-risk HR 3.5, p < 0.001, compared to low risk). On-treatment mGPS was also prognostic in patients with progressive disease (PD, intermediate risk HR 1.7, p = 0.033, high-risk HR 2.9, p < 0.001, compared to low risk). Remarkably, patients with PD and low-risk mGPS at first staging had a higher 12-month survival probability compared to patients with SD with intermediate or high-risk mGPS (67.0% vs 64.0%/47.7%).

Conclusions

Integrating on-treatment biomarkers into imaging-based staging can improve outcome prediction. A multi-modal approach to response assessment more akin to current practice in many hematologic malignancies should be further investigated in solid oncology, particularly in the context of immunotherapy.

Clinical trial identification

NCT02008227.

Editorial acknowledgement

This publication is based on research using data from data contributors Roche that has been made available through Vivli, Inc. Vivli has not contributed to or approved, and is not in any way responsible for, the contents of this publication.

Legal entity responsible for the study

The authors.

Funding

BONFOR (Medical Faculty, University of Bonn), German Research Foundation (DFG).

Disclosure

All authors have declared no conflicts of interest.