Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors combined with chemotherapy in first-line treatment in an advanced non-small cell lung cancer patient with EGFR sensitive mutation

Incorporation of EGFR mutation status into M descriptor of new TNM classification influences survival curves in non-small cell lung cancer patients

Background The 8th edition of tumor node metastasis (TNM) staging system for lung cancer introduced a revision of M descriptor. The limitation of new classification to predict prognosis is its focus on anatomical extent of the disease only. Information on molecular status of the tumor significantly influences treatment response and survival; however, data addressing this issue is scarce. This report points to the impact of epidermal growth factor receptor (EGFR) mutation in non-small cell lung cancer (NSCLC) patients on survival in view of new M descriptors of TNM classification system. Patients and methods Medical records of 479 consecutive metastatic NSCLC patients treated between 2009 and 2011, all tested for EGFR mutations, were retrospectively reviewed. For 355 patients medical records included sufficient information to be appropriately categorized into one of the new subgroups according to the M descriptor in 8th TNM classification, of those 89 (25.1%) patients harboured EGFR mutations (EGFR-m). Results Median overall survival (mOS) of EGFR-m patients was significantly longer than mOS of patients without EGFR mutations (20.6 months vs. 8.3 months, p < 0.001). Patients with limited disease burden (M1b sub-group) had the longest mOS among EGFR wild type patients (EGFR-wt) and also among EGFR-m patients, 14.4 months and 39.2 month, respectively. In spite of widespread metastatic disease of M1c EGFR-m patients, their mOS (18.8 months) was longer than mOS of oligometastatic EGFR-wt patients (M1b), who had the lowest disease burden (14.4 months). Median follow up was 53.9 months. Conclusions Incorporation of EGFR mutation status in advanced NSCLC further differentiates survival curves of M categories in 8th TNM classification and more precisely predicts survival compared to number of metastasis or number of metastatic sites alone.

Evaluation of osimertinib efficacy according to body surface area and body mass index in patients with non-small cell lung cancer harboring an EGFR mutation: A prospective observational study

BACKGROUND

Osimertinib is recommended for non-small cell lung cancer (NSCLC) patients with EGFR mutation; however, it is unclear whether body size variables affect the efficacy of osimertinib in such patients. This study assessed the potential effect of body surface area (BSA) and body mass index (BMI) on osimertinib chemotherapy in patients with T790M-positive advanced NSCLC who progress on prior EGFR-tyrosine kinase inhibitors (TKIs).

METHODS

We conducted a prospective observational cohort study. Median BSA and BMI were used as cut-off values to evaluate the impact of body size variables on osimertinib chemotherapy.

RESULTS

The median BSA and BMI of 47 patients were 1.50 m² and 21.5 kg/m² , respectively. Clinical outcomes did not significantly differ between the high and low BSA groups, with response rates of 59.1% and 56.0% (P = 0.83) and progression-free survival (PFS) of 7.6 and 9.1 months (P = 0.69), respectively. Similarly, there were no significant differences between the high and low BMI groups relative to response rates, which were 60.8% and 54.1% (P = 0.64), respectively, and PFS, which was 7.6 months in both groups (P = 0.38). No significant differences were observed among toxicity profiles in relation to BSA or BMI. Multivariate analysis identified better performance status, young age, and EGFR exon 19 deletion as independent favorable predictors of PFS.

CONCLUSION

The efficacy of osimertinib does not significantly vary relative to body size variables of patients with T790M-positive NSCLC who progress on prior EGFR-TKIs.