72 research outputs found
A Flexible-Hazards Cure Model With application to Patients With Soft Tissue Sarcoma
In medical research, it is often of great interest to have an accurate estimation of cure rates by different treatment options and for different patient groups. If the follow-up time is sufficiently long and the sample size is large, the proportion of cured patients will make the Kaplan-Meier estimator of survival function have a flat plateau at its tail, whose value indicates the overall cure rate. However, it may be difficult to estimate and compare the cure rates for all the subsets of interest in this way, due to the limit of sample sizes and curse of dimensionality. In the current literature, most regression models for estimating cure rates assume proportional hazards (PH) between different subgroups. It turns out that the estimation of cure rates for subgroups is highly sensitive to this assumption, so more flexible models are needed, especially when this PH assumption is clearly violated. We propose a new cure model to simultaneously incorporate both PH and non-PH scenarios for different covariates. We develop a stable and easily implementable iterative procedure for parameter estimation through maximization of the nonparametric likelihood function. The covariance matrix is estimated by adding perturbation weights to the estimation procedure. In simulation studies, the proposed method provides unbiased estimation for the regression coefficients, survival curves, and cure rates given covariates, while existing models are biased. Our model is applied to a study of stage III soft tissue sarcoma and provides trustworthy estimation of cure rates for different treatment and demographic groups
Serum CA 19-9 as a Marker of Resectability and Survival in Patients with Potentially Resectable Pancreatic Cancer Treated with Neoadjuvant Chemoradiation
Purpose
The role of carbohydrate antigen (CA) 19-9 in the evaluation of patients with resectable pancreatic cancer treated with neoadjuvant therapy prior to planned surgical resection is unknown. We evaluated CA 19-9 as a marker of therapeutic response, completion of therapy, and survival in patients enrolled on two recently reported clinical trials.
Patients and Methods
We analyzed patients with radiographically resectable adenocarcinoma of the head/uncinate process treated on two phase II trials of neoadjuvant chemoradiation. Patients without evidence of disease progression following chemoradiation underwent pancreaticoduodenectomy (PD). CA 19-9 was evaluated in patients with a normal bilirubin level.
Results
We enrolled 174 patients, and 119 (68%) completed all therapy including PD. Pretreatment CA 19-9 <37 U/ml had a positive predictive value (PPV) for completing PD of 86% but a negative predictive value (NPV) of 33%. Among patients without evidence of disease at last follow-up, the highest pretreatment CA 19-9 was 1,125 U/ml. Restaging CA 19-9 <61 U/ml had a PPV of 93% and a NPV of 28% for completing PD among resectable patients. The area under the receiver-operating characteristics curve of pretreatment and restaging CA 19-9 levels for completing PD was 0.59 and 0.74, respectively. We identified no association between change in CA 19-9 and histopathologic response (P = 0.74).
Conclusions
Although the PPV of CA 19-9 for completing neoadjuvant therapy and undergoing PD was high, its clinical utility was compromised by a low NPV. Decision-making for patients with resectable PC should remain based on clinical assessment and radiographic staging.PublishedN/
Contemporary guideline-directed medical therapy in de novo, chronic, and worsening heart failure patients:First data from the TITRATE-HF study
Aims: Despite clear guideline recommendations for initiating four drug classes in all patients with heart failure (HF) with reduced ejection fraction (HFrEF) and the availability of rapid titration schemes, information on real-world implementation lags behind. Closely following the 2021 ESC HF guidelines and 2023 focused update, the TITRATE-HF study started to prospectively investigate the use, sequencing, and titration of guideline-directed medical therapy (GDMT) in HF patients, including the identification of implementation barriers. Methods and results: TITRATE-HF is an ongoing long-term HF registry conducted in the Netherlands. Overall, 4288 patients from 48 hospitals were included. Among these patients, 1732 presented with de novo, 2240 with chronic, and 316 with worsening HF. The median age was 71 years (interquartile range [IQR] 63–78), 29% were female, and median ejection fraction was 35% (IQR 25–40). In total, 44% of chronic and worsening HFrEF patients were prescribed quadruple therapy. However, only 1% of HFrEF patients achieved target dose for all drug classes. In addition, quadruple therapy was more often prescribed to patients treated in a dedicated HF outpatient clinic as compared to a general cardiology outpatient clinic. In each GDMT drug class, 19% to 36% of non-use in HFrEF patients was related to side-effects, intolerances, or contraindications. In the de novo HF cohort, 49% of patients already used one or more GDMT drug classes for other indications than HF. Conclusion: This first analysis of the TITRATE-HF study reports relatively high use of GDMT in a contemporary HF cohort, while still showing room for improvement regarding quadruple therapy. Importantly, the use and dose of GDMT were suboptimal, with the reasons often remaining unclear. This underscores the urgency for further optimization of GDMT and implementation strategies within HF management.</p
Less bleeding by omitting aspirin in non-ST-segment elevation acute coronary syndrome patients: Rationale and design of the LEGACY study
BACKGROUND: Early aspirin withdrawal, also known as P2Y12-inhibitor monotherapy, following percutaneous coronary intervention (PCI) for non-ST-segment elevation acute coronary syndrome (NSTE-ACS) can reduce bleeding without a trade-off in efficacy. Still the average daily bleeding risk is highest during the first months and it remains unclear if aspirin can be omitted immediately following PCI. METHODS: The LEGACY study is an open-label, multicenter randomized controlled trial evaluating the safety and efficacy of immediate P2Y12-inhibitor monotherapy versus dual antiplatelet therapy (DAPT) for 12 months in 3,090 patients. Patients are randomized immediately following successful PCI for NSTE-ACS to 75-100 mg aspirin once daily versus no aspirin. The primary hypothesis is that immediately omitting aspirin is superior to DAPT with respect to major or minor bleeding defined as Bleeding Academic Research Consortium type 2, 3, or 5 bleeding, while maintaining noninferiority for the composite of all-cause mortality, myocardial infarction and stroke compared to DAPT. CONCLUSIONS: The LEGACY study is the first randomized study that is specifically designed to evaluate the impact of immediately omitting aspirin, and thus treating patients with P2Y12-inhibitor monotherapy, as compared to DAPT for 12 months on bleeding and ischemic events within 12 months following PCI for NSTE-ACS
Contemporary guideline-directed medical therapy in de novo, chronic, and worsening heart failure patients: First data from the TITRATE-HF study
AIMS: Despite clear guideline recommendations for initiating four drug classes in all patients with heart failure (HF) with reduced ejection fraction (HFrEF) and the availability of rapid titration schemes, information on real-world implementation lags behind. Closely following the 2021 ESC HF guidelines and 2023 focused update, the TITRATE-HF study started to prospectively investigate the use, sequencing, and titration of guideline-directed medical therapy (GDMT) in HF patients, including the identification of implementation barriers. METHODS AND RESULTS: TITRATE-HF is an ongoing long-term HF registry conducted in the Netherlands. Overall, 4288 patients from 48 hospitals were included. Among these patients, 1732 presented with de novo, 2240 with chronic, and 316 with worsening HF. The median age was 71 years (interquartile range [IQR] 63-78), 29% were female, and median ejection fraction was 35% (IQR 25-40). In total, 44% of chronic and worsening HFrEF patients were prescribed quadruple therapy. However, only 1% of HFrEF patients achieved target dose for all drug classes. In addition, quadruple therapy was more often prescribed to patients treated in a dedicated HF outpatient clinic as compared to a general cardiology outpatient clinic. In each GDMT drug class, 19% to 36% of non-use in HFrEF patients was related to side-effects, intolerances, or contraindications. In the de novo HF cohort, 49% of patients already used one or more GDMT drug classes for other indications than HF. CONCLUSION: This first analysis of the TITRATE-HF study reports relatively high use of GDMT in a contemporary HF cohort, while still showing room for improvement regarding quadruple therapy. Importantly, the use and dose of GDMT were suboptimal, with the reasons often remaining unclear. This underscores the urgency for further optimization of GDMT and implementation strategies within HF management
Venous resection in pancreatic cancer surgery
Vascular resection and reconstruction at the time of pancreaticoduodenectomy (PD) adds complexity to an already demanding operation. In this chapter, we review the indications, surgical techniques, and most recent results of venous resection combined with PD. The need for venous resection may not always be apparent on preoperative imaging, and surgeons who perform PD should be familiar with standard techniques necessary for vascular resection and reconstruction. Recent data suggest that with proper patient selection and surgeon experience, vascular resection and reconstruction can be performed safely and does not impact survival duration even in patients with pancreatic ductal adenocarcinoma. The median survival of patients who underwent PD and required vascular resection was 23 months, approximately 1 year longer than the survival of patients with locally advanced, surgically unresectable pancreatic cancer who receive palliative chemotherapy or chemoradiation
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