Integrated histological and molecular analyses of rebiopsy samples at osimertinib progression improve post-progression survivals: A single-center retrospective study.

BACKGROUND: This single-center retrospective cohort study sought to investigate the impact of rebiopsy analysis after osimertinib progression in improving the survival outcomes. METHODS: Eighty-nine patients with EGFR T790M-positive advanced NSCLC who received second- or further-line osimertinib between January 2017 and July 2019 were included in this study. The co-primary study endpoints were post-progression progression-free survival (pPFS), defined as the time from osimertinib progression until progression from further-line treatment, and post-progression overall survival (pOS), defined as the time from osimertinib progression until death or the last follow-up date. RESULTS: Pairwise analysis revealed that receiving targeted therapy as further-line treatment after osimertinib progression did not statistically improve the pPFS (P = 0.285) or the pOS (P = 0.903) compared to chemotherapy. However, patients who submitted rebiopsy samples at osimertinib progression for histological and molecular analyses, particularly those who had actionable markers and received highly matched therapy, had significantly longer pPFS and pOS as compared to those who received low-level matched therapy (pPFS = 10.0 m vs. 4.1 m, P = 0.005; pOS = 19.4 m vs. 10.0 m, P = 0.023), unmatched therapy (pPFS = 10.0 m vs. 4.7 m, P = 0.009; pOS = 19.4 m vs. 7.0 m, P = 0.001), and those without rebiopsy data (Rebiopsy vs Non-rebiopsy; pPFS = 6.1 m vs. 3.3 m, P = 0.014; pOS = 11.7 m vs. 6.8 m, P = 0.011). CONCLUSION: Our real-world cohort study demonstrates that integrated histological and molecular analyses of rebiopsy specimens after osimertinib progression could provide more opportunities for individualized treatments to improve the post-progression survival of patients with advanced NSCLC. Our findings provide clinical evidence that supports the inclusion of NGS-based analysis of rebiopsy specimens as standard-of-care after osimertinib progression and warrants further prospective evaluation.

Evaluation of Real-Time PCR Coupled With Multiplex Probe Melting Curve Analysis for Pathogen Detection in Patients With Suspected Bloodstream Infections.

Background: This study aimed to evaluate real-time polymerase chain reaction coupled with multiplex probe melting curve analysis (PCR-MCA) for pathogen detection in patients with suspected bloodstream infections (BSIs). Methods: A PCR-MCA assay was developed for simultaneous identification of 28 kinds of the most common pathogens and two resistance genes within a few hours. The diagnostic performance of the PCR-MCA assay was determined and compared to the results of blood culture. Results: A total of 2,844 consecutive new episodes of suspected BSIs in 2,763 patients were included in this study. There were 269 episodes of pathogens identified by blood culture. For all the pathogens tested, the PCR-MCA assay exhibited a sensitivity of 88.8% (239/269), specificity of 100% (2,575/2,575), and agreement of 98.9% (2,814/2,844). For the pathogens on the PCR-MCA list, the PCR-MCA results had a sensitivity of 99.2% (239/241), specificity of 100% (2,575/2,575), and agreement of 99.9% (2,814/2,816) compared with the results of blood culture. For seven samples with multiple pathogens identified simultaneously during one blood culture investigation, the PCR-MCA assay verified the results of the blood culture, with an agreement rate of 100% for each. Conclusion: The PCR-MCA assay could discover 88.8% of the pathogens in clinical practice, showing excellent diagnostic performance vs. that of blood culture for pathogen detection in patients with suspected BSIs, and would contribute to rapid diagnosis and correct antibiotic administration.

A survey of five broad-host-range plasmids in gram-negative bacilli isolated from patients.

OBJECTIVES: To learn the prevalence of the primary classical broad-host-range (BHR) IncA/C, IncN, IncP, IncQ, and IncW plasmids in dominant gram-negative bacilli from inpatients in a teaching hospital in southern China. METHODS: A multiplex polymerase chain reaction based on the replicons of BHR IncA/C, IncN, IncP, IncQ, and IncW plasmids was developed and used to determine these BHR plasmids. The difference in prevalence rates among the different species from three specimens was evaluated by a binary logistic regression model and the differences between multidrug-resistant organisms (MDRO) and non-MDRO were assessed using a chi-square test. RESULTS: The average positive detection percentages of the replicons were 4.3%, 3.7%, 3.0%, 2.6%, and 1.9%, respectively, for IncN, IncP, IncQ, IncW, and IncA/C in descending order. The distribution of all five BHR plasmids did not differ significantly between specimens collected from wounds and urine, although both were significantly higher than those of sputum. The prevalence rates of all five BHR plasmids in MDROs were significantly higher than those in non-MDRO for Enterobacteriaceae; however, no significant difference was seen in non-fermenting gram-negative bacilli (NFGNB). CONCLUSIONS: BHR IncA/C, IncN, IncP, IncQ, and IncW plasmids, which occur more often in bacilli from wound and urine specimens than those of sputum, are widespread in Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Pseudomonas aeruginosa, and Acinetobacter baumannii strains isolated from inpatients. The prevalence rates in MDRO are higher than those in non-MDRO for Enterobacteriaceae but not significantly different for NFGNB.