Novel Resistance Mechanisms Including L1196Q, P1094H, and R1248_D1249 Insertion in Three Patients With NSCLC After ALK Tyrosine Kinase Inhibitor Treatment.

OBJECTIVES: The purposes of this study are to clarify the details of the ALK tyrosine kinase inhibitor (TKI) resistance mechanism in rebiopsy cases and to predict novel resistance gene alterations using molecular dynamics simulation. METHODS: A total of 21 patients with ALK-positive NSCLC who underwent a rebiopsy after ALK TKI failure were included in this analysis. ALK fluorescence in situ hybridization and reverse transcription polymerase chain reaction were performed with paired initial and rebiopsy tumor specimens. RESULTS: Nine patients had no known ALK resistance mechanisms. Four had ALK amplification. L1196M, I1171N, and G1269A, mutations that are known to indicate resistance to ALK TKIs, were detected in one patient each. Small cell carcinoma and sarcomatoid transition were found in one case each. L1196Q, P1094H, and exon 24 76-base pair insertion were detected after the second-generation ALK TKIs. CONCLUSIONS: The combination of a genetic analysis and a computational simulation model may make a prediction of resistance mechanisms for overcoming ALK TKI resistance, and the construction of a genomic and simulation fused database is important for the development of personalized medicine in this field.

Efficacy of local therapy for oligoprogressive disease after programmed cell death 1 blockade in advanced non-small cell lung cancer.

Immune checkpoint inhibitors (ICIs) have dramatically changed the strategy used to treat patients with non-small-cell lung cancer (NSCLC); however, the vast majority of patients eventually develop progressive disease (PD) and acquire resistance to ICIs. Some patients experience oligoprogressive disease. Few retrospective studies have evaluated clinical efficacy in patients with oligometastatic progression who received local therapy after ICI treatment. We conducted a retrospective analysis of advanced NSCLC patients who received PD-1 inhibitor monotherapy with nivolumab or pembrolizumab to evaluate the effects of ICIs on the patterns of progression and the efficacy of local therapy for oligoprogressive disease. Of the 307 patients treated with ICIs, 148 were evaluated in our study; 42 were treated with pembrolizumab, and 106 were treated with nivolumab. Thirty-eight patients showed oligoprogression. Male sex, a lack of driver mutations, and smoking history were significantly correlated with the risk of oligoprogression. Primary lesions were most frequently detected at oligoprogression sites (15 patients), and 6 patients experienced abdominal lymph node (LN) oligoprogression. Four patients showed evidence of new abdominal LN oligometastases. There was no significant difference in overall survival (OS) between the local therapy group and the switch therapy group (reached vs. not reached, P = .456). We summarized clinical data on the response of oligoprogressive NSCLC to ICI therapy. The results may help to elucidate the causes of ICI resistance and indicate that the use of local therapy as the initial treatment in this setting is feasible treatment option.

Efficacy and Safety Data of Osimertinib in Elderly Patients with NSCLC Who Harbor the EGFR T790M Mutation After Failure of Initial EGFR-TKI Treatment.

BACKGROUND/AIM: The aim of this study was to evaluate the safety and efficacy of osimertinib for elderly patients, since the data remain limited. PATIENTS AND METHODS: A total of 77 patients with advanced non-small cell lung cancer (NSCLC) harboring the epidermal growth factor receptor (EGFR) T790M mutation and treated with osimertinib were reviewed. Efficacy and safety indicators, such as EGFR-tyrosine kinase inhibitor (TKI)-related adverse events (AEs) and osimertinib-associated hematotoxicity, were evaluated in elderly patients (elderly group, EG; age, ≥75 years) by comparing them with younger patients (non-EG; aged <75 years). The frequency of AEs associated with osimertinib was compared with the initial EGFR-TKI treatment before osimertinib administration in the same patient cohort. RESULTS: Of the total 77 patients, 18 (23%) were assigned to the EG, whereas 59 (77%) were assigned to the non-EG. There were no significant differences in overall response rate and progression-free survival between the two groups. Regarding the safety of osimertinib, the EG had significantly more grade ≥2 paronychia than the non-EG (16.6% vs. 1.6%, p=0.04). Additionally, the maximum grade of EGFR-TKI-related AEs associated with osimertinib in the EG was significantly lower than that of the initial EGFR-TKI treatment (p=0.03). CONCLUSION: Osimertinib is a safe and effective treatment option for elderly patients with advanced NSCLC who harbor the EGFR mutation.

Dramatic intracranial response to osimertinib in a poor performance status patient with lung adenocarcinoma harboring the epidermal growth factor receptor T790M mutation: A case report.

We herein report a case of dramatic intracranial response to osimertinib in a poor performance status patient with lung adenocarcinoma harboring the epidermal growth factor receptor (EGFR) T790M mutation encoded in exon 20. The patient was a 59-year-old woman with EGFR exon 19 deletion-positive lung adenocarcinoma, who relapsed with multiple brain metastases. Computed tomography-guided biopsy of the left pleural tumor revealed adenocarcinoma harboring an EGFR exon 19 deletion and an EGFR T790M mutation encoded in exon 20. The patient was treated with osimertinib, a third-generation EGFR tyrosine kinase inhibitor. Two days after treatment initiation, the patient displayed profound disturbance of consciousness, possibly due to carcinomatous meningitis, and treatment had to be discontinued due to difficulty in taking osimertinib. However, the patient gradually started to recover consciousness and, after 3 days, she was again able to take osimertinib. One month after the initiation of osimertinib treatment, magnetic resonance imaging revealed an apparent reduction in brain metastases. The patient is currently under continued treatment with osimertinib. At the last follow-up (February, 2017) she exhibited partial response to the treatment.

Risk of tumor flare after nivolumab treatment in patients with irradiated field recurrence.

Nivolumab offers a statistically superior survival benefit over docetaxel in patients with advanced, previously treated squamous and non-squamous non-small-cell lung cancer (NSCLC). However, we unexpectedly encountered "tumor flare" that was associated with initially increased tumor lesion size and subsequently decreased tumor burden in patients with NSCLC treated with nivolumab, which is known as pseudoprogression. Tumor flare with rapid progression related to accelerated progression after nivolumab treatment has also been observed. Here we report two patients having early irradiated field recurrence who experienced "tumor flare" that showed pseudoprogression and rapid progression. In addition, we present a brief literature review on "tumor flare" after nivolumab treatment.

CYFRA 21-1 as a Predictive Marker for Non-small Cell Lung Cancer Treated with Pemetrexed-based Chemotherapy.

BACKGROUND: Pretreatment serum tumor marker levels predict outcome in non-small cell lung cancer (NSCLC). However, little is known about the clinical value of such measurements for patients treated with pemetrexed plus a platinum-derivative. PATIENTS AND METHODS: We retrospectively screened 100 chemotherapy-naïve patients with advanced non-squamous NSCLC treated with pemetrexed plus a platinum-derivative in relation to the pretreatment level of cytokeratin 19 fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA). RESULTS: Sixty one patients with a high CYFRA 21-1 level had statistically shorter progression-free and overall survival than 39 patients with a normal CYFRA 21-1 level (median progression-free survival=127 days vs. 191 days, respectively; p=0.046; median overall survival=360 days vs. 781 days, respectively, p<0.001). Serum CEA level was not related to survival. CONCLUSION: Serum CYFRA 21-1 level is a predictive and prognostic marker in patients with NSCLC treated with pemetrexed plus a platinum-derivative.