Clinical outcomes of ALK+ non-small cell lung cancer in Denmark

BACKGROUND

Real-world clinical outcomes of anaplastic lymphoma kinase positive (ALK+) non-small cell lung cancer (NSCLC) patients vary. This study aimed to investigate the treatment and clinical outcomes of all ALK+ NSCLC patients in Denmark in the period 2011-2018, regardless of disease stage.

MATERIALS AND METHODS

A national pathology database with complete coverage was used to identify ALK+ NSCLC patients diagnosed between 2011 and 2018. Clinical data were obtained through retrospective chart reviews. Overall survival (OS) and duration of treatment (DOT) were analyzed using Kaplan-Meier methodologies.

RESULTS

A total of 209 ALK+ NSCLC patients were included. The cohort had a slight overrepresentation of female patients (56.5%) with a mean age of 61.6 years. Most patients were adenocarcinoma cases (97%) and presented with an ECOG performance status of 0-1 (79%). Stage IIIb-IVb patients comprised 70% of the cohort. The use of ALK-tyrosine kinase inhibitors (TKIs) as first-line treatment increased over time, with the 1st generation ALK-TKI crizotinib being the predominant treatment in the 1st line. In 1st line treatment, 2nd generation ALK-TKIs had a median DOT more than twice the median DOT of crizotinib (25.1 and 9.1 months, respectively). The median OS for the entire cohort was 44.0 months. Patients with stage I-IIIA disease had a median OS that had not been reached, while those with stage IIIb-IVb disease had a median OS of 31.8 months. Patients with stage IIIb-IVb disease receiving an ALK-TKI as 1st line treatment had a median OS of 42.5 months with immature follow-up. Brain metastases at diagnosis or choice of 1st line treatment did not statistically significantly impact OS.

CONCLUSION

This study gives insights into the treatment and outcome of ALK+ NSCLC patients in Denmark and provides a real-world confirmation of the superior disease control provided by 2nd generation ALK-TKIs as compared to the 1st generation ALK-TKI crizotinib.

Tumoral PD-L1 does not impact time to treatment discontinuation in EGFR mutated non-small cell lung cancer patients treated with EGFR tyrosine kinase inhibitor—a Danish cohort study

Background

Not all non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations respond equally to therapy with tyrosine kinase inhibitors (TKIs). Programmed death ligand-1 (PD-L1) has previously been speculated as a possible biomarker for treatment outcome because of its positive correlation with these mutations in cell lines, but clinical studies have yielded conflicting results. We investigate the predictive potential of this surface protein in relation to clinical benefit in patients as measured by time to treatment discontinuation (TTD).

Methods

We screened 516 Danish patients with EGFR mutations for inclusion based on a history of TKI treatment and a PD-L1 status that was assessed no earlier than three months prior to treatment initiation. Patients were stratified according to their expression of the potential biomarker as either negative (0%), low (1–49%) or high (≥50%). We employed the Kaplan-Meier method and the log rank test to test for a difference in treatment duration according to PD-L1 expression.

Results

We included 111 Danish patients. The median follow-up time from inclusion until death or censoring at the end of the study was 670 days (range, 32–1,664 days, 95% CI: 502–897 days). Fifty-seven patients (51%) categorized as PD-L1 expression negative, 32 (29%) as low and 22 (20%) as high. We tested for differences in treatment duration between the three groups. Our tests did not yield statistically significant P values.

Conclusions

In our cohort of 111 Danish patients with NSCLC harboring mutations in the epidermal growth factor receptor gene, expression levels of PD-L1 did not significantly impact the duration of clinical benefit from tyrosine kinase treatment.