The AGAMENON-SEOM model for prediction of survival in patients with advanced HER2-positive oesophagogastric adenocarcinoma receiving first-line trastuzumab-based therapy

Background

Trastuzumab and chemotherapy is the standard first-line treatment in human epidermal growth factor receptor 2 (HER2)-positive advanced gastro-oesophageal cancer. The objective was to develop a predictive model for overall survival (OS) and progression-free survival (PFS) in patients treated with trastuzumab.

Methods

Patients with HER2-positive advanced gastro-oesophageal adenocarcinoma (AGA) from the Spanish Society of Medical Oncology (SEOM)-AGAMENON registry and treated first line with trastuzumab and chemotherapy between 2008 and 2021 were included. The model was externally validated in an independent series (The Christie NHS Foundation Trust, Manchester, UK).

Results

In all, 737 patients were recruited (AGAMENON-SEOM, n = 654; Manchester, n = 83). Median PFS and OS in the training cohort were 7.76 [95% confidence interval (CI), 7.13-8.25] and 14.0 months (95% CI, 13.0-14.9), respectively. Six covariates were significantly associated with OS: neutrophil-to-lymphocyte ratio, Eastern Cooperative Oncology Group performance status, Lauren subtype, HER2 expression, histological grade and tumour burden. The AGAMENON-HER2 model demonstrated adequate calibration and fair discriminatory ability with a c-index for corrected PFS/OS of 0.606 (95% CI, 0.578-0.636) and 0.623 (95% CI, 0.594-0.655), respectively. In the validation cohort, the model is well calibrated, with a c-index of 0.650 and 0.683 for PFS and OS, respectively.

Conclusion

The AGAMENON-HER2 prognostic tool stratifies HER2-positive AGA patients receiving trastuzumab and chemotherapy according to their estimated survival endpoints.

Multistate Models: Accurate and Dynamic Methods to Improve Predictions of Thrombotic Risk in Patients with Cancer

Research into cancer-associated thrombosis (CAT) entails managing dynamic data that pose an analytical challenge. Thus, methods that assume proportional hazards to investigate prognosis entail a risk of misinterpreting or overlooking key traits or time-varying effects. We examined the AGAMENON registry, which collects data from 2,129 patients with advanced gastric cancer. An accelerated failure time (AFT) multistate model and flexible competing risks regression were used to scrutinize the time-varying effect of CAT, as well as to estimate how covariates dynamically predict cumulative incidence. The AFT model revealed that thrombosis shortened progression-free survival and overall survival with adjusted time ratios of 0.72 and 0.56, respectively. Nevertheless, its prognostic effect was nonproportional and disappeared over time if the subject managed to survive long enough. CAT that occurred later had a more pronounced prognostic effect. In the flexible competing risks model, multiple covariates were seen to have significant time-varying effects on the cumulative incidence of CAT (Khorana score, secondary thromboprophylaxis, high tumor burden, and cisplatin-containing regimen), whereas other predictors exerted a constant effect (signet ring cells and primary thromboprophylaxis). The model that assumes proportional hazards was incapable of capturing the effect of these covariates and predicted the cumulative incidence in a biased way. This study evinces that flexible and multistate models are a useful and innovative method to describe the dynamic effect of variables associated with CAT and should be more widely used.

Anthracycline-based triplets do not improve the efficacy of platinum-fluoropyrimidine doublets in first-line treatment of advanced gastric cancer: real-world data from the AGAMEMON National Cancer Registry

BACKGROUND

Although anthracycline-based triplets are one of the most widely used schedules to treat advanced gastric cancer (AGC), the benefit of including epirubicin in these therapeutic combinations remains unknown. This study aims to evaluate both the efficacy and tolerance of triplets with epirubicin vs. doublets with platinum-fluoropyrimidine in a national AGC registry.

METHODS

Patients with AGC treated with polychemotherapy without trastuzumab at 28 hospitals in Spain between 2008 and 2016 were included. The effect of anthracycline-based triplets against doublets was evaluated by propensity score matching (PSM) and Cox proportional hazards (PH) regression.

RESULT

A total of 1002 patients were included (doublets, n = 653; anthracycline-based triplets, n = 349). The multivariable Cox PH regression failed to detect significantly increased OS in favor of triplets with anthracyclines: HR 0.90 (95% CI, 0.78-1.05), p = 0.20035. After PSM, the sample contained 325 pairs with similar baseline characteristics. This method was also unable to reveal an increase in OS: 10.5 (95% CI, 9.7-12.3) vs. 9.9 (95% CI, 9.2-11.4) months, HR 0.91 (CI 95%, 0.76-1.083), and (log-rank test, p = 0.226). Response rates (42.1 vs. 33.1%, p = 0.12) and PFS (HR 0.95, CI 95%, 0.80-1.13, log-rank test, p = 0.873) were not significantly higher with epirubicin-based regimens. The triplets were associated with greater grade 3-4 hematological toxicity, and increased hospitalization due to toxicity by 68%. The addition of epirubicin is viable, but 23.7% discontinued treatment because of adverse effects or patient decision.

CONCLUSION

Anthracyclines added to platinum-fluoropyrimidine doublets did not improve the response rate or survival outcomes in patients with AGC but entailed greater toxicity.

Efficacy and safety of chemotherapy in older versus non-older patients with advanced gastric cancer: A real-world data, non-inferiority analysis

OBJECTIVE

Advanced gastric cancer (AGC) is a common neoplasm in older adults. Nevertheless, there are few specific management data in the literature. The aim of this study was to assess non-inferiority of survival and efficacy-related outcomes of chemotherapy used in older vs non-older patients with AGC.

MATERIALS AND METHODS

We recruited 1485 patients from the AGAMENON registry of AGC treated with polychemotherapy between 2008-2017. A statistical analysis was conducted to prove non-inferiority for overall survival (OS) associated with the use of chemotherapy schedules in individuals ≥70 vs.<70years. The fixed-margin method was used (hazard ratio [HR]<1.176) that corresponds to conserving at least 85% efficacy.

RESULTS

33% (n=489) of the cases analyzed were ≥70 years. Two-agent chemotherapies and combinations with oxaliplatin (48% vs. 29%) were used more often in the older patients, as were modified schedules and/or lower doses. Toxicity grade 3-4 was comparable in both groups, although when looking at any grade, there were more episodes of enteritis, renal toxicity, and fatigue in older patients. In addition, toxicity was a frequent cause for discontinuing treatment in older patients. The response rate was similar in both groups. After adjusting for confounding factors, the non-inferiority of OS associated with schedules administered to the older vs. younger subjects was confirmed: HR 1.02 (90% CI, 0.91-1.14), P (non inferiority)=0.018, as well as progression-free survival: HR 0.97 (90% CI, 0.87-1.08), P(non-inferiority)=0.001.

CONCLUSION

In this AGC registry, the use of chemotherapy with schedules adapted to patients ≥70 years provided efficacy that was not inferior to that seen in younger cases, with comparable adverse effects.

Prognostic significance of performing universal HER2 testing in cases of advanced gastric cancer

BACKGROUND

Trastuzumab significantly improves overall survival (OS) when added to cisplatin and fluoropyrimidine as a treatment for HER2-positive advanced gastric cancers (AGC). The aim of this study was to evaluate the impact of the gradual implementation of HER2 testing on patient prognosis in a national registry of AGC.

METHODS

This Spanish National Cancer Registry includes cases who were consecutively recruited at 28 centers from January 2008 to January 2016. The effect of missing HER2 status was assessed using stratified Cox proportional hazards (PH) regression.

RESULTS

The rate of HER2 testing increased steadily over time, from 58.3 % in 2008 to 92.9 % in 2016. HER2 was positive in 194 tumors (21.3 %). In the stratified Cox PH regression, each 1 % increase in patients who were not tested for HER2 at the institutions was associated with an approximately 0.3 % increase in the risk of death: hazard ratio, 1.0035 (CI 95 %, 1.001-1.005), P = 0.0019. Median OS was significantly lower at institutions with the highest proportions of patients who were not tested for HER2.

CONCLUSION

Patients treated at centers that took longer to implement HER2 testing exhibited worse clinical outcomes. The speed of implementation behaves as a quality-of-care indicator. Reviewed guidelines on HER2 testing should be used to achieve this goal in a timely manner.

In VitroActivity of Telithromycin, Quinupristin/Dalfopristin, Linezolid and Comparator Antimicrobial Agents AgainstStaphylococcus aureusClinical Isolates

We have studied the prevalence of the different macrolide, lincosamide, streptograminB (MLS(B)) phenotypes among clinical Staphylococcus aureus isolates erythromycin- and/or oxacillin-resistant; and also the activity of other antimicrobial agents including telithromycin, quinupristin/dalfopristin, linezolid, aminoglycosides, chloramphenicol and vancomycin. We found that 64.86% of S. aureus were oxacillin-resistant. While the most prevalent MLS(B) phenotype among methicillin-resistant S. aureus (MRSA) was constitutive MLS(B) (cMLS) (83%), among methicillin-susceptible S. aureus (MSSA) it was inducible MLS(B) (iMLS(B)) (90%). Kanamycin resistance was more frequent than resistance to other aminoglycosides, being 100% for MRSA. Telithromycin was only active against iMLS(B), MS and erythromycin-susceptible isolates, although resistance rates were found among iMLS(B) MSSA (2.78%). Quinupristin/dalfopristin showed greater activity, with resistance rates of 2.5% for MRSA and 1.53% for MSSA. Both vancomycin and linezolid were fully active against all the isolates tested, with the highest MIC value being 2 microg/ml and 4 microg/ml, respectively. Among MRSA strains, 81.67% displayed resistance to five or more antimicrobials. This multiresistance was more frequently found among cMLS(B) strains (96.38% MRSA resistant to 6-9 agents).

Novel 10-bp deletion in the translational attenuator of a constitutively expressed erm(A) gene from Staphylococcus epidermidis

Alterations in the erm(A) regulatory region of six clinical isolates of Staphylococcus epidermidis and one of Staphylococcus haemolyticus displaying a constitutive resistance phenotype were investigated. Anovel deletion of 10 bp with respect to the corresponding sequence of Tn554 was identified in the attenuator of a constitutively expressed erm(A) gene of one of the S. epidermidis isolates. Thus far, this is the smallest deletion conferring constitutive resistance in the translational attenuator of erm(A) in a naturally occurring S. epidermidis strain of human origin.

Detection of the aminoglycosidestreptothricin resistance gene cluster ant(6)-sat4-aph(3 ')-III in commensal viridans group streptococci

High-level aminoglycoside resistance was assessed in 190 commensal erythromycin-resistant alpha-hemolytic streptococcal strains. Of these, seven were also aminoglycoside-resistant: one Streptococcus mitis strain was resistant to high levels of kanamycin and carried the aph(3 ')-III gene, four S. mitis strains were resistant to high levels of streptomycin and lacked aminoglycoside-modifying enzymes, and two S. oralis strains that were resistant to high levels of kanamycin and streptomycin harbored both the aph(3 ')-III and the ant(6) genes. The two S. oralis strains also carried the ant(6)-sat4- aph(3 ' ')-III aminoglycoside-streptothricin resistance gene cluster, but it was not contained in a Tn5405-like structure. The presence of this resistance gene cluster in commensal streptococci suggests an exchange of resistance genes between these bacteria and enterococci or staphylococci.

Epidemiological study of resistance to nalidixic acid and other antibiotics in clinical Yersinia enterocolitica O:3 isolates

Forty-six Yersinia enterocolitica O:3 clinical isolates resistant to nalidixic acid were studied. The use of molecular typing techniques, other indicators of resistance patterns, the plasmid profile, and the presence of genes that encode aminoglycoside-modifying enzyme production suggested to us a clonal dissemination of the studied strains.