This phase I trial was conducted to determine the maximum tolerated dose (MTD) and recommended dose of afatinib for phase II trial in elderly patients with advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations. The study used a standard 3 + 3 dose escalation design. Patients aged 75 years or older with advanced NSCLC harboring EGFR mutations were enrolled. The doses of afatinib, which were given once daily, were planned as follows: level 1, 20 mg/day; level 2, 30 mg/day; level 3, 40 mg/day. Dose-limiting toxicity (DLT) was defined as grade 4 hematologic, persistent grade > 2 diarrhea for > 2 days despite concomitant medications or grade 3 non-hematologic toxicity. DLT was evaluated during day 1–28. Fifteen patients were enrolled. Patient characteristics were: male/female 3/12; median age 79 (range 75–87); PS 0/1, 2/13. Six patients have been treated at levels 1 and 3, and three patients at level 2. At level 1, one of six patients experienced grade 3 rush, grade 3 anorexia, and grade 3 infection as DLTs. At level 2, none of three patients experienced a DLT. At level 3, two patients developed grade 3 diarrhea, one of whom also experienced grade 3 anorexia. Most frequent adverse events of any grade were diarrhea, paronychia, rush, and nausea. Most patients at level 2 and 3 required dose reduction in 3 months. MTD was defined as 40 mg/day, and recommended dose for phase II study in elderly patients was 30 mg/day.

Afatinib, a second-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) for mutant nonsmall cell lung cancer (NSCLC), was approved in Japan in 2014. This study evaluated clinical outcomes of afatinib in realworld practice. Medical records of patients who received afatinib for advanced EGFR-mutant NSCLC were retrospectively reviewed. In total, 128 patients were analyzed. Seventy-six patients received afatinib as the first-line setting and 52 as the re-challenge setting (i.e., after failure of prior first-generation TKI). There was no difference in patient characteristics, such as age, sex, and PS, between the first-line and the re-challenge settings. In the first-line setting, the median progression-free survival (PFS) was 17.8 months (95% confidence interval [CI] 13.7-21.5 months). The overall survival (OS) was 39.5 months (95% CI 34.4-not reached). The response rate (RR) was 64.4%. Subset analysis indicated that patients with dose reduction showed longer PFS than those without dose reduction (18.5 months versus 7.9 months) (P = 0.016). In the re-challenge setting, the median PFS was 8.0 months (95% CI 4.9-9.5 months). The RR was 25%. Most common adverse events leading to dose modification or treatment discontinuation included diarrhea, paronychia, and oral mucositis in both settings. Interstitial lung disease occurred in 5.4% (7/128). In the real-world practice in Japan, afatinib showed comparable or better efficacy compared with that shown in previous clinical trials in both the first-line and the re-challenge settings.

Pembrolizumab has become the standard first‐line treatment for non‐small cell lung cancer (NSCLC) patients with high PD‐L1expression. MET exon 14 skipping is a rare mutation typically found in older, female, and non‐smoking patients with NSCLC. Herein, we report the case of a 71‐year‐old non‐smoking woman who was diagnosed with NSCLC in the left lung. EGFR mutation and ALK fusion were not detected. Because the biopsy specimen showed high PD‐L1 expression with a tumor proportion score of 95%, pembrolizumab was introduced as first‐line therapy, but resulted in no clinical benefit. The patient was subsequently administered chemotherapy with carboplatin and pemetrexed, leading to remarkable tumor shrinkage. A next‐generation sequencing panel analysis revealed a MET exon 14 skipping mutation. Thus, pembrolizumab might not be effective for NSCLC patients with MET exon 14 skipping mutations, even if PD‐L1 expression is high.

A de novo single-nucleotide mutation in the EGFR gene can cause the development of lung cancer. EGFR tyrosine kinase inhibitors (EGFR-TKIs) are used for clinical treatment of such lung cancers, but acquired resistance often mitigates their efficacy. Accordingly, monitoring of de novo and acquired nucleotide mutations is essential for clinical treatment of lung cancers with EGFR-TKIs. Previously, we reported that oligoribonucleotide interference-PCR (ORNi-PCR) can accurately and cost-effectively detect single-nucleotide mutations. In this study, we applied ORNi-PCR to simultaneous detection of the de novo L858R and acquired T790M mutations in the EGFR gene in lung cancer cells. First, we established optimal experimental conditions for ORNi-PCR to simultaneously detect the two single-nucleotide mutations in genomic DNA from lung cancer cells. The conditions we established could also be used for ORNi-PCR using complementary DNA reverse-transcribed from extracted RNA. We found that ORNi-PCR could detect lung cancer cells possessing both single-nucleotide mutations among a large number of cells harboring wild-type sequences, even when the cancer cells constituted less than ~0.2% of all cells. Our findings demonstrate that ORNi-PCR can simultaneously detect multiple single-nucleotide mutations in a gene of interest and might therefore be useful for simultaneous detection of EGFR mutations in clinical examinations.

Lorlatinib, a third-generation ALK tyrosine kinase inhibitor, has been approved as a treatment for ALK-positive lung cancer. This review provides information regarding the pharmacology and clinical features of lorlatinib, including its efficacy and associated adverse events. Pivotal clinical trials are discussed along with the current status of lorlatinib as a treatment for ALK-positive lung cancer and future therapeutic challenges.