RESUMO
The immune checkpoint inhibitor atezolizumab is approved for PD-L1-positive triple-negative breast cancer (TNBC). However, no activity of atezolizumab in PD-L1-negative TNBC has been reported to date. Here, we present the case study of a woman with TNBC with low tumor infiltrating lymphocytes and PD-L1-negative disease, which achieved a significant response to atezolizumab monotherapy and durable response after the combination of atezolizumab and nab-paclitaxel. The comprehensive genomic analysis that we performed in her tumor and plasma samples revealed high tumor mutational burden (TMB), presence of the APOBEC genetic signatures, high expression of the tumor inflammation signature, and a HER2-enriched subtype by the PAM50 assay. Some of these biomarkers have been shown to independently predict response to immunotherapy in other tumors and may explain the durable response in our patient. Our work warrants further translational studies to identify biomarkers of response to immune checkpoint inhibitors in TNBC beyond PD-L1 expression and to better select patients that will benefit from immunotherapy.
RESUMO
BACKGROUND: We aimed to describe the epidemiology of catheter-related bloodstream infections (CRBSIs) in onco-hematological neutropenic patients during a 25-year study period, to evaluate the risk factors for Gram-negative bacilli (GNB) CRBSI, as well as rates of inappropriate empirical antibiotic treatments (IEAT) and mortality. MATERIALS/METHODS: All consecutive episodes of CRBSIs were prospectively collected (1994-2018). Changing epidemiology was evaluated comparing five-year time spans. A multivariate regression model was built to evaluate risk factors for GNB CRBSIs. RESULTS: 482 monomicrobial CRBSIs were documented. The proportion of CRBSIs among all BSIs decreased over time from 41.2% to 15.8% (p<0.001). CRBSIs epidemiology has been changing: the rate of GNB increased over time (from 11.9% to 29.4%; p<0.001), as well as the absolute number and rate of multidrug-resistant (MDR) GNB (from 9.5% to 40.0%; p = 0.039). P. aeruginosa increased and comprised up to 40% of all GNB. Independent factors related with GNB-CRBSIs were: longer duration of in-situ catheter (OR 1.007; 95%CI 1.004-1.011), older age (OR 1.016; 95%CI 1.001-1.033), prior antibiotic treatment with penicillins (OR 2.716; 95%CI 1.306-5.403), and current antibiotic treatment with glycopeptides (OR 1.931; 95%CI 1.001-3.306). IEATs were administered to 30.7% of patients, with the highest percentage among MDR P. aeruginosa (76.9%) and S. maltophillia (92.9%). Mortality rate was greater among GNB than GPC-CRBSI (14.4% vs 5.4%; p = 0.002), with mortality increasing over time (from 4.5% to 11.2%; p = 0.003). CONCLUSION: A significant shift towards GNB-CRBSIs was observed. Secondarily, and coinciding with an increasing number of GNB-MDR infections, mortality increased over time.