Real-world treatment patterns and survival of patients with ROS1 rearranged stage IV non-squamous NSCLC in the Netherlands.

INTRODUCTION: Rearrangement of c-ros oncogene 1 (ROS1) is a rare gene alteration in patients with stage IV non-squamous non-small cell lung cancer (NSCLC). Molecular testing for ROS1 is recommended to enable primary treatment with tyrosine kinase inhibitors (TKI). Aim of this study was to describe real-world treatment patterns and survival for patients with ROS1 in the Netherlands. METHODS: All non-squamous NSCLC stage IV patients, diagnosed 2015-2019, were identified from the population-based Netherlands Cancer Registry (N = 19,871). For patients with ROS1 rearrangements (ROS1+ ) who received first line TKI, additional information about progression and second-line treatment was retrieved by active follow-up. Overall survival (OS) and progression-free survival (PFS) were calculated using Kaplan-Meier estimators. RESULTS: A total of 67 patients (0.43%) were diagnosed with a ROS1+ NSCLC. Systemic treatment was administered in 75% which was most often TKI (n = 34) followed by chemotherapy (n = 14). Two-year OS for patients receiving upfront TKI versus other systemic treatment was 53% (95% CI 35-68) and 50% (95% CI 25-71), respectively. For patients receiving TKI, median OS was 24.3 months. Survival was inferior in case of brain metastasis (BM) at diagnosis (5.2 months). One in five patients receiving TKI as a first line treatment had BM at diagnosis, of the remaining 22 another 9 developed BM during follow up. PFS was also inferior for patients with BM at diagnosis with a median PFS of 4.3 months versus 9.0 without BM. CONCLUSION: In this real-world population of ROS1+ NSCLC patients, only half received primary treatment with TKI. Overall survival and PFS during TKI were disappointing, mainly related to brain metastasis. TKI treatment with agents that have intra-cranial activity may be beneficial in this patient population and our results confirm the importance of performing an MRI of the brain as part of the standard diagnostic work up in patients with ROS1+ NSCLC.

A population-based study describing characteristics, survival and the effect of TKI treatment on patients with EGFR mutated stage IV NSCLC in the Netherlands.

INTRODUCTION: Since 2011, treatment guidelines advise targeted therapy (tyrosine kinase inhibitor, TKI) for patients with activating epidermal growth factor receptor (EGFR) mutations (EGFR+) in non-small cell lung cancer (NSCLC). We describe characteristics, first line treatment and survival of patients diagnosed with EGFR+ NSCLC in a European population, focussing on age, gender and trends over time and compare to the whole group and EGFR-. METHODS: All patients with non-squamous NSCLC stage IV, diagnosed 2011-2018, were identified from the population-based Netherlands Cancer Registry (N = 31,291). RESULTS: Among all, 7.0% were registered to be EGFR+, with highest prevalence in females <40 years (16%). Median overall survival (OS) ranged from 3.5 months in the EGFR- group >65 years to 23.6 months in the EGFR+ group <50 years treated with TKI. Over time, OS for the whole group increased by 0.6 months, of which 33% due to TKI treatment in EGFR+. The increase was strongest in females <50 years, where median OS almost doubled to 12.4 months. In the EGFR+, multivariable hazard of death was most strongly associated with the use of TKI (HR 0.45(0.41-0.49)). Of the patients with EGFR+ this space need or not, 71% received TKI treatment. Being young reduced the hazard of death (HR 0.71(95%CI:0.59-0.85)) irrespective of treatment, while male gender increased the hazard of death (HR 1.22(95%CI:1.11-1.33)). CONCLUSION: At population level, TKI treatment in patients with non-squamous NSCLC stage IV EGFR+  has very strong beneficial effects on outcome. Of the improvement in OS that was made over the years for the whole group, about one third seems to be attributed to TKI treatment in EGFR+ patients.

Tumour growth rate as a tool for response evaluation during PD-1 treatment for non-small cell lung cancer: a retrospective analysis.

BACKGROUND: Immune checkpoint inhibitors have emerged as a standard of care treatment for non-small cell lung cancer (NSCLC). To get insight into variations in tumour growth kinetics and their potential predictive values for outcome, we evaluated tumour growth rate (TGR) in patients receiving programmed cell death 1 (PD-1) checkpoint inhibitors. PATIENTS AND METHODS: Differences in TGR before and after the start of treatment were calculated by entering the sum of the longest diameters from computer tomography scans before and after the initiation of therapy into a formula that assumes volumetric exponential tumour growth. TGR variations, possible predictors for TGR changes and its relationship to overall survival (OS) were studied. For comparison, tumour response was assessed using Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. RESULTS: Among the 58 evaluable patients, 37 patients (64%) showed deceleration of TGR and 16 patients (27%) showed an acceleration of TGR after initiation of therapy, with a significant difference in median OS of 18.0 months versus 6.0 months (hazard ratio 0.35, 95% CI 0.18-0.71) between these groups. Four patients (7%) were defined as having hyperprogressive disease. In five patients (9%), tumour growth remained stable. These TGR categories were not significantly different according to age, sex, histology, smoking or previous radiotherapy. Of the patients defined as having progressive disease by RECIST version 1.1 at first follow-up, 40% showed response to checkpoint inhibitors by a decrease in TGR. CONCLUSION: Tumour growth kinetics can be used as a clinically relevant predictor for OS in anti-PD-1-treated patients with NSCLC, and may provide additional information to RECIST measurements.