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The WJOG8815L phase II clinical study involves patients with non‐small cell lung cancer (NSCLC) that harbored the EGFR T790M mutation, which confers resistance to EGFR tyrosine kinase inhibitors (TKIs). The purpose of this study was to assess the predictive value of monitoring EGFR genomic alterations in circulating tumor DNA (ctDNA) from patients with NSCLC that undergo treatment with the third‐generation EGFR‐TKI osimertinib. Plasma samples of 52 patients harboring the EGFR T790M mutation were obtained pretreatment (Pre), on day 1 of treatment cycle 4 (C4) or cycle 9 (C9), and at diagnosis of disease progression or treatment discontinuation (PD/stop). CtDNA was screened for EGFR‐TKI‐sensitizing mutations, the EGFR T790M mutation, and other genomic alterations using the cobas EGFR Mutation Test v2 (cobas), droplet digital PCR (ddPCR), and targeted deep sequencing. Analysis of the sensitizing—and T790M—EGFR mutant fractions (MFs) was used to determine tumor mutational burden. Both MFs were found to decrease during treatment, whereas rebound of the sensitizing EGFR MF was observed at PD/stop, suggesting that osimertinib targeted both T790M mutation‐positive tumors and tumors with sensitizing EGFR mutations. Significant differences in the response rates and progression‐free survival were observed between the sensitizing EGFR MF‐high and sensitizing EGFR MF‐low groups (cutoff: median) at C4. In conclusion, ctDNA monitoring for sensitizing EGFR mutations at C4 is suitable for predicting the treatment outcomes in NSCLC patients receiving osimertinib (Clinical Trial Registration No.: UMIN000022076).

Abbreviations

CIs
confidence intervals
ctDNA
circulating tumor DNA
ddPCR
droplet digital PCR
EGFR
epidermal growth factor receptor
MFs
mutant fractions
NGS
next‐generation sequencing
NSCLC
non‐small cell lung cancer
ORR
overall response rate
OS
overall survival
PD
progressive disease
PFS
progression‐free survival
PR
partial response
SD
stable disease
TKI
tyrosine kinase inhibitor
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BackgroundLocomotive syndrome is a condition of reduced mobility due to problems with locomotive organs. Although lumbar spinal canal stenosis is one of the major diseases constituting locomotive syndrome, only few studies have focused on the association between the two pathologies. We aimed to investigate the effect of surgery on lumbar spinal canal stenosis with respect to locomotive syndrome using various physical function tests, including locomotive syndrome risk tests, before and after surgery.MethodsClinical data of 101 consecutive patients (male = 46; female = 55; mean age, 69.3 years) who underwent surgery for lumbar spinal canal stenosis at our institute were prospectively collected. Results of physical function tests, including stand-up test, two-step test, and 25-Question Geriatric Locomotive Function Scale, and the sagittal vertical axis were evaluated before and 1 year after surgery. The association between several parameters and improvement of risk level in locomotive syndrome was evaluated.ResultsIn the total assessment, 93.1% of cases were in stage 2 and 6.9% in stage 1 preoperatively, while 72.4% were in stage 2, 22.4% in stage 1, and 5.2% in stage 0 at 1 year postoperatively. Postoperative improvement in the total assessment was observed in 28.7% of cases. Several physical function tests and sagittal vertical axis showed significant improvement after surgery. On multiple logistic regression analysis, age >75 years (odds ratio = 10.9, confidence interval = 1.09–109) and postoperative sagittal vertical axis >40 mm (odds ratio = 17.8, confidence interval = 1.78–177) were significant risk factors associated with non-improvement in risk level of locomotive syndrome.ConclusionsSurgical treatment for lumbar spinal canal stenosis improved physical function, including locomotive syndrome. Risk factors associated with non-improvement of locomotive syndrome were later-stage elderly and postoperative sagittal balance impairment.  相似文献   
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A 3‐month‐old boy developed small papules on his trunk. After the papules increased in number, the patient was diagnosed with Langerhans cell histiocytosis based on the pathological findings. He was referred to our department for further examination. Upon initial examination, the papules and nodules were scattered on his back, abdomen and lumbar region. Because he did not present with any organ involvement except the skin, he was diagnosed with single‐system and skin‐limited Langerhans cell histiocytosis. Skin rashes were treated with a topical steroid and started regressing 3 months after onset. All papules disappeared 6 months after onset. In this boy, the Langerhans cell histiocytosis tumor cells expressed phosphorylated extracellular signal‐regulated kinases. In Langerhans cell histiocytosis, BRAF V600E and other genes are known to mutate to act as driver mutations in stem cells of the myeloid dendritic cell lineage. Consequently, extracellular signal‐regulated kinases are continuously activated, which contributes to Langerhans cell histiocytosis carcinogenesis.  相似文献   
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Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis.  相似文献   
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