scholarly journals Conditional Transformation Models for Survivor Function Estimation

2015 ◽  
Vol 11 (1) ◽  
Author(s):  
Lisa Möst ◽  
Torsten Hothorn
Keyword(s):  
Survival Data ◽  
Proportional Hazards ◽  
Patient Characteristics ◽  
Patient Specific ◽  
Survival Times ◽  
Transformation Models ◽  
Survivor Function ◽  
Conditional Transformation ◽  
The Impact ◽  
Survivor Functions

AbstractIn survival analysis, the estimation of patient-specific survivor functions that are conditional on a set of patient characteristics is of special interest. In general, knowledge of the conditional survival probabilities of a patient at all relevant time points allows better assessment of the patient’s risk than summary statistics, such as median survival time. Nevertheless, standard methods for analysing survival data seldom estimate the survivor function directly. Therefore, we propose the application of conditional transformation models (CTMs) for the estimation of the conditional distribution function of survival times given a set of patient characteristics. We used the inverse probability of censoring weighting approach to account for right-censored observations. Our proposed modelling approach allows the prediction of patient-specific survivor functions. In addition, CTMs constitute a flexible model class that is able to deal with proportional as well as non-proportional hazards. The well-known Cox model is included in the class of CTMs as a special case. We investigated the performance of CTMs in survival data analysis in a simulation that included proportional and non-proportional hazard settings and different scenarios of explanatory variables. Furthermore, we re-analysed the survival times of patients suffering from chronic myelogenous leukaemia and studied the impact of the proportional hazards assumption on previously published results.

Differences in survival for metastatic colorectal cancer patients by lines of therapy received.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e14016-e14016
Author(s):  
Brian S. Seal ◽  
Benjamin Chastek ◽  
Mahesh Kulakodlu ◽  
Satish Valluri
Keyword(s):  
Proportional Hazards ◽  
Survival Rates ◽  
Patient Characteristics ◽  
Cox Proportional Hazards ◽  
Research Database ◽  
First Line ◽  
Cox Proportional Hazards Models ◽  
Stage 4 ◽  
Similar Survival ◽  
The Impact

e14016 Background: Improvements in survival for advanced-stage CRC patients who receive chemotherapy have been reported. We compared survival rates for patients with 3+ vs. <3 lines of therapy. Methods: Adult patients with a diagnosis of CRC between 01/01/05 and 05/31/10 were identified from the Impact Intelligence Oncology Management (IIOM) registry. Patients with either stage 4 CRC at original diagnosis or development of metastasis were included. Registry data included original stage and date of diagnosis. Linked healthcare claims from the Life Sciences Research Database, a large US health insurance database affiliated with OptumInsight, were used to identify lines of therapy after metastases and patient characteristics. Death data were obtained from the Social Security Administration’s master death file. Patients were categorized by number of lines of therapy received (0, 1, 2, 3+) and original stage at diagnosis (0-2, 3, 4, unknown). Survival following metastases was evaluated using Cox proportional hazards models controlling for lines of therapy received, stage, and other patient characteristics. Results: 598 patients, followed for a mean of 653 days after becoming metastatic, were included. Mean unadjusted length of follow-up was lowest among patients who received no chemotherapy (516 days) or only 1 line (511 days), and increased to 627 days for those with 2 lines and 930 days for those with 3+ lines. However, multivariate analysis indicated that patients with 3+ lines had comparable survival vs. those with 0 (HR=0.79), 1 (HR=1.59), or 2 (HR=1.15) lines of therapy (p>0.05 for all comparisons). Compared to patients who presented with stage 4 CRC, those who progressed from stage 0-2 (HR=1.22), stage 3 (HR=0.83), or unknown stage (HR=1.18) had similar survival after metastases (p>0.05 for all comparisons). After excluding 94 patients who didn’t receive chemotherapy, patients treated with an oxaliplatin-based regimen (HR=1.28; p=0.24) in first line had similar survival compared to patients treated with an irinotecan-based or anti-EGFR regimen in first line. Conclusions: Lines of therapy received and initial stage were not associated with survival after development of metastases.

Any regression of tumor (ART) within 12 weeks versus RECIST 1.1 response category as an intermediate endpoint to assess the activity of immune checkpoint inhibitors (ICIs) for metastatic urothelial carcinoma (mUC).

2020 ◽  
Vol 38 (6_suppl) ◽  
pp. 473-473
Author(s):  
Catherine Curran ◽  
Gregory Russell Pond ◽  
Amin Nassar ◽  
Sarah Abou Alaiwi ◽  
Bradley Alexander McGregor ◽  
...  
Keyword(s):  
Survival Data ◽  
Tumor Size ◽  
Proportional Hazards ◽  
Checkpoint Inhibitors ◽  
Cox Proportional Hazards ◽  
P Value ◽  
Prognostic Effect ◽  
Recist 1.1 ◽  
Metastatic Urothelial Carcinoma ◽  
The Impact

473 Background: Many ICIs are approved to treat mUC following platinum-based chemo and as 1st-line therapy for selected patients (pts). While RECIST 1.1 responses are generally durable and associated with prolonged survival, the benefit of ICIs extends beyond this group of pts. Stable disease (SD) consists of a heterogeneous population of pts with both increase and decrease in tumor size and is confounded by the impact of pre-ICI disease pace. We hypothesized that in the setting of ICIs, any regression of tumor (ART) within 12 weeks may capture early benefit and correlate with survival more comprehensively than RECIST 1.1. Methods: mUC pts who received an ICI following platinum-based chemo at DFCI were eligible for analysis. Pts were required to have tumor size changes, RECIST 1.1 response by week 12 and survival data available. Demographics and prognostic factors were collected. Descriptive stats were calculated, and univariable Cox proportional hazards regression analysis was conducted to examine the prognostic effect of ART and RECIST 1.1 with overall survival (OS). Results: 104 pts were evaluable. The median age was 66 (range 34-89). 71% were male. The numbers of pts with ART and RECIST1.1 partial response (PR) were 45 (43.3%) and 32 (30.1%), respectively. Univariable analyses identified an association between ART and RECIST 1.1 response with OS (p<0.001). The 1-year OS (95% CI) for ART vs. no ART was 83.6 % (68.7, 91.8) and 35.9 % (23.1, 48.8), while the 1-year OS (95% CI) for RECIST 1.1 response vs. no response was 81.3% (62.9, 91.1) and 45.6% (32.9, 57.4), respectively. RECIST 1.1 category was not significantly associated with OS (p-value=0.68) after adjusting for ART; however, statistically, ART associated with OS (p=0.002) after adjusting for RECIST 1.1 category. The modest size of this cohort is a limitation. Conclusions: ART within 12 weeks is identified early and is robustly associated with OS in pts with mUC receiving post-platinum ICIs. ART may serve as a more optimal intermediate endpoint for survival compared to RECIST 1.1 in the setting of ICIs. Evaluating this endpoint in other malignancies is warranted.

scholarly journals MP12: Emergency department boarding: predictors and outcomes

CJEM ◽  
2018 ◽  
Vol 20 (S1) ◽  
pp. S44-S44
Author(s):  
L. Salehi ◽  
V. Jegatheeswaran ◽  
J. Herman ◽  
P. Phalpher ◽  
R. Valani ◽  
...  
Keyword(s):  
Critical Care ◽  
Patient Care ◽  
High Volume ◽  
Patient Characteristics ◽  
Patient Specific ◽  
Medicine Service ◽  
Comorbidity Burden ◽  
Ed Overcrowding ◽  
Ed Visits ◽  
The Impact

Introduction: Delays in transfer to an in-patient bed of admitted patients boarded in the ED has been identified as one of the chief drivers of ED overcrowding. Our study aims to replicate findings from a previous study in identifying patient characteristics associated with increased boarding time, and the impact of increased boarding time on in-patient length of stay (IPLOS). Methods: We conducted a retrospective single-centre observational study during the period between January 1, 2015 December 31, 2015 at a very high volume community hospital (~ 75,000 ED visits/year). All patients admitted from the ED to Medicine, Pediatrics, Surgery, and Critical Care were identified. The mean time to in-patient bed (TTB), as well as patient-specific and institutional factors that were associated with prolonged boarding times ( 12 hours) were identified. Mean IP LOS was calculated for those with prolonged boarding times and compared to those without prolonged boarding times. Results: There were 8,096 unique admissions during the study period. Patients admitted to the Medicine service exhibited significantly higher boarding times than those admitted to other services, with a mean boarding time of 17.4 hrs, as compared to 4.2 hrs, 5.7 hrs, and 4.0 hrs for those admitted to Surgery, Critical Care and Pediatrics respectively. Within Medicine patients, there was a statistically significant greater odds of prolonged boarding time for patients who were older, had a greater comorbidity burden, and required more specialized in-patient care (i.e. an isolation bed or telemetry bed). Medicine patients with prolonged boarding times also experienced 0.7 days longer IP LOS, even after correcting for age and comorbidity (mean adjusted IP LOS 10.6 days versus 11.3 days). Conclusion: Within our study period, older, sicker patients and those patients requiring more resource-intensive in-patient care have the longest ED boarding times. These prolonged ‘boarding’ times are associated with significantly increased IP LOS.

Poor FEV1 or DLco on Pre-Transplant PFT Does Not Compromise Outcomes In Patients Undergoing a Reduced-Intensity Allogeneic Progenitor Cell Transplant.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1322-1322
Author(s):  
Manish Sharma ◽  
Rima M. Saliba ◽  
Muzaffar H. Qazilbash ◽  
Grace-Julia Okoroji ◽  
Uday Popat ◽  
...  
Keyword(s):  
Proportional Hazards ◽  
Conflicts Of Interest ◽  
Univariate Analysis ◽  
Patient Characteristics ◽  
Cancer Center ◽  
Control Group ◽  
Study Group ◽  
Cell Transplant ◽  
The Impact ◽  
Reduced Intensity

Abstract Abstract 1322 Background: Pre-transplant work-up prior to an allogeneic stem cell transplant (allo-SCT) generally includes pulmonary functions tests (PFT) with assessment of FEV1 and DLco. It has been previously published that patients with a DLco or FEV1 less than 60% of predicted have higher non-relapse mortality (NRM) when undergoing a myeloablative allo-SCT. However, the PFT criteria for selecting candidates for a reduced intensity (RI) allogeneic transplant allo-SCT remains poorly investigated. We performed a retrospective analysis to assess the impact of low FEV1 or DLco on NRM and overall survival (OS) in patients undergoing a RI allo-SCT. Methods: All patients who underwent a RI allo-SCT for hematological malignancies at MD Anderson Cancer Center from Jan 2000 to April 2009 were included. Using Cox's proportional hazards regression, we compared the rate of NRM and OS between patients who had a pre-transplant FEV1 or DLco > 50% (control group) prior to a RI allo-SCT and those with FEV1 and DLco < 50% (study group). The cumulative incidence of NRM was estimated considering disease progression as a competing risk. Actuarial OS was estimated by the Kaplan-Meier method. Results: Patient characteristics are presented in Table 1. There were no statistically significant differences between the study and control groups except for age and sex. A significantly higher proportion of patients were > 50 years in the control group (65%) compared with the low PFT group (45%, P=0.02) and there were more males in the control group (P=.001). The median FEV1 and DLco in the study group was 55% (28-111) and 47% (33-98) of predicted, respectively. On univariate analysis abnormal PFTs did not impact OS at 30 months (HR 1.1, 95% CI 0.7–1.8, P=0.7) or NRM at 1 year (HR 1.3, (95% CI 0.6–2.7, P=0.4). Active disease at SCT, and a diagnosis of CLL, NHL or HL were associated with significantly worse OS and NRM, whereas age >50 years was only associated with worse OS. Low PFT had no significant impact on OS and NRM when evaluated separately in patients older or younger than 50 years old. Conclusion: Our experience suggests that a low (<50% of predicted) FEV1 or a DLco on pre-transplant evaluation does not adversely impact NRM and OS after RI allo-SCT. These findings need to be validated in a multivariate analysis. Disclosures: No relevant conflicts of interest to declare.

High-dose carmustine (BCNU), etoposide (VP-16), cytarabine (Ara-C), and cyclophosphamide-BVAC with autologous transplant (ASCT) in relapsed and refractory Hodgkin disease (HD): Long-term follow-up of 89 patients

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 8068-8068
Author(s):  
T. Iyengar ◽  
M. Hayashi ◽  
C. Leopold ◽  
B. J. Smith ◽  
R. Gingrich ◽  
...  
Keyword(s):  
Survival Data ◽  
Proportional Hazards ◽  
Conditioning Regimen ◽  
Disease Free Survival ◽  
High Dose Chemotherapy ◽  
Cox Proportional Hazards ◽  
High Dose ◽  
Preparative Regimen ◽  
The Impact

8068 Background: High dose chemotherapy followed by ASCT has been established as the therapy for refractory and relapsed HD. Relapse remains the primary contributor to an unsuccessful outcome after ASCT. Intensification of the conditioning regimen is one means of decreasing relapse and improving results. We report our experience with an augmented preparative regimen in patients (pts) with relapsed or refractory HD undergoing ASCT. Methods: Retrospective analysis of 89 consecutive pts from October 1984 to October 2004. All pts received high-dose chemotherapy with BCNU 600mg/m2 IV day -8, Etoposide 400mg/m2/day days -7, -6, -5, and -4, Ara-C 3gm/m2 IV every 12 hours for 8 doses starting day -7, and Cyclophosphamide 90mg/kg IV on day-2 followed by bone marrow (40 pts), peripheral blood (43 pts) or both (6 pts) rescue. Ten pts received planned XRT post-transplant. Survival data were estimated using Kaplan-Meier curves. Cox proportional hazards regression was used to assess the impact of variables on disease-free survival (DFS) and overall survival (OS). Results: A total of 89 pts were identified. Median age was 31 (range 16–62); 51 pts (57.3%) had received one prior therapy at the time of transplant. At transplant only 28 pts (34.6%) were in CR; 79.8% had sensitive disease (CR plus PR).Time to transplant was < 1 year for 17% of pts. With a median follow-up of 811 days, the 5 and 10-year DFS rates were 63.3% and 60.4%, respectively. The estimated 5 and 10- year OS rates were 47.3% and 33.7%. The rate of secondary malignancies at 10 years was 7.8%. Lack of B symptoms and stage at transplant were associated with improved DFS (p= 0.01 and p= 0.0005, respectively) and OS (p=0.002 and p=0.02, respectively). Patients with primary induction failure and resistant relapse did as well as patients with sensitive disease. Conclusions: Though ASCT has been beneficial in prolonging DFS and OS in pts with chemosensitive HD, there has been conflicting data regarding refractory disease. We propose that an intensified regimen, i.e. BVAC, may be of benefit in that setting. Only a large randomized trial can determine whether intensification of the preparative regimen can improve OS for such a population. No significant financial relationships to disclose.

The Joint Analysis of Survival Times and Response Rates in Clinical Trials on the Treatment of Cancer

1980 ◽  
Vol 19 (02) ◽  
pp. 112-114 ◽  
Author(s):  
J. Wahrendorf
Keyword(s):  
Clinical Trial ◽  
Survival Data ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Time Dependent ◽  
Joint Analysis ◽  
Survival Times ◽  
Logrank Test ◽  
Hazards Model ◽  
Time Dependent Covariates

A method is outlined which allows to analyse survival and response data from a clinical trial on the treatment of cancer when the question of interest is whether the somehow defined response to the treatment has an influence on patients’ survival times. This can be done by making use of Cox’s proportional hazards model for survival data together with time-dependent covariates. This allows an appropriate classification of non-respondors and responders by considering the time of diagnosis of response during follow-up. The resulting test can be viewed as a time-dependent logrank test. An example from a clinical trial on gastrointestinal cancer is considered.

scholarly journals THE IMPACT OF SUBJECTIVE WELL-BEING ON LONGEVITY AMONG OLDER ADULTS

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S313-S314
Author(s):  
Sylvia Y Wang ◽  
Giyeon Kim ◽  
Ansley Gilpin
Keyword(s):  
Older Adults ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Well Being ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
Medical Illness ◽  
Subjective Well Being ◽  
Survival Times ◽  
The Impact

Abstract Objectives: People tend to believe happier people live longer. However, relatively few empirical studies have examined the influence of subjective well-being (SWB) on longevity among older adults. Thus, our study investigated the impact of SWB on longevity among older adult using national representative longitudinal data in the U.S. Methods: Drawn from the National Health and Aging Trends Study, 6,757 older adults aged 65 or older with completed information of SWB from 2011 were selected and followed until 2017 annually. The Kaplan-Meier estimator was used to estimate the survival time between different levels of SWB without covariates. In addition, the Cox Proportional Hazards Model was used to investigate the impact of SWB on longevity while adjusting the influences of covariates. Results: We found that a higher level of SWB predicted longer survival times among older adults. The impact of SWB on survival times remained to be significant, but weaker, after adjusting the influences of age, educational attainment, household income, gender, marital status, number of health insurances, self-rated health, chronical medical illness, and mental health. Conclusion: Findings suggest that happier older adults live longer. Recognizing the importance of SWB on longevity, healthcare providers should develop programs promoting higher SWB to prolong life for older adults.

scholarly journals Predicting Hospital Length of Stay at Admission Using Global and Country-Specific Competing Risk Analysis of Structural, Patient, and Nutrition-Related Data from nutritionDay 2007–2015

Nutrients ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 4111
Author(s):  
Noemi Kiss ◽  
Michael Hiesmayr ◽  
Isabella Sulz ◽  
Peter Bauer ◽  
Georg Heinze ◽  
...  
Keyword(s):  
Length Of Stay ◽  
Proportional Hazards ◽  
Patient Characteristics ◽  
Hospital Length ◽  
Cox Proportional Hazards ◽  
Hospital Length Of Stay ◽  
Hospital Death ◽  
Event Analysis ◽  
Related Data ◽  
The Impact

Hospital length of stay (LOS) is an important clinical and economic outcome and knowing its predictors could lead to better planning of resources needed during hospitalization. This analysis sought to identify structure, patient, and nutrition-related predictors of LOS available at the time of admission in the global nutritionDay dataset and to analyze variations by country for countries with n > 750. Data from 2006–2015 (n = 155,524) was utilized for descriptive and multivariable cause-specific Cox proportional hazards competing-risks analyses of total LOS from admission. Time to event analysis on 90,480 complete cases included: discharged (n = 65,509), transferred (n = 11,553), or in-hospital death (n = 3199). The median LOS was 6 days (25th and 75th percentile: 4–12). There is robust evidence that LOS is predicted by patient characteristics such as age, affected organs, and comorbidities in all three outcomes. Having lost weight in the last three months led to a longer time to discharge (Hazard Ratio (HR) 0.89; 99.9% Confidence Interval (CI) 0.85–0.93), shorter time to transfer (HR 1.40; 99.9% CI 1.24–1.57) or death (HR 2.34; 99.9% CI 1.86–2.94). The impact of having a dietician and screening patients at admission varied by country. Despite country variability in outcomes and LOS, the factors that predict LOS at admission are consistent globally.

scholarly journals Peridural Anesthesia and Cancer-Related Survival after Surgery for Pancreatic Cancer—A Retrospective Cohort Study

2021 ◽  
Vol 11 (3) ◽  
pp. 532-542
Author(s):  
Andrea Alexander ◽  
Nadja Lehwald-Tywuschik ◽  
Alexander Rehders ◽  
Stefanie Rabenalt ◽  
Pablo E. Verde ◽  
...  
Keyword(s):  
Overall Survival ◽  
Pancreatic Adenocarcinoma ◽  
Survival Data ◽  
Oncological Outcome ◽  
Patient Characteristics ◽  
Radical Resection ◽  
Proportional Hazard ◽  
General Anesthetics ◽  
Peridural Anesthesia ◽  
The Impact

Background: In patients with prostatic and breast cancer the application of peridural anesthesia (PDA) showed a beneficial effect on prognosis. This was explained by reduced requirements for general anesthetics and perioperative opioids as well as a lower perioperative stress level. The impact of PDA in patients with more aggressive types of cancer has not been completely elucidated. Here, we analyzed the prognostic influence of PDA on overall survival after surgery as primary in patients that underwent radical resection of pancreatic adenocarcinoma. Methods: Records of 98 consecutive patients were reviewed. In 70 of these cases PDA was applied. Patient characteristics such as demographics, TNM stage, and operative data were retrospectively collected from medical records and analyzed. Survival data were analyzed by Cox’s proportional hazard regression model. Results: Overall, no significant prognostic influence of PDA on recurrence or overall survival (p = 0.762, Hazard Ratio [HR] 0.884, 95% confidence interval [CI] 0.398–1.961) was found. However, there was a trend towards a longer overall survival (p = 0.069, HR 0.394, 95% CI 0.144–1.078) associated with PDA in a subgroup of patients with better differentiation of pancreatic adenocarcinoma. Conclusion: The observation of longer survival associated with PDA in our subgroup of patients with better-differentiated pancreatic carcinomas is in line with previous reports on various other less aggressive tumor entities. Our results indicate that PDA might improve the oncological outcome of patients with pancreatic adenocarcinoma.

Racial and socioeconomic disparities in the treatment of resectable hepatocellular carcinoma.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e19026-e19026
Author(s):  
Young soo Rho ◽  
Ian Pagano ◽  
Jared David Acoba
Keyword(s):  
Hepatocellular Carcinoma ◽  
Survival Data ◽  
Proportional Hazards ◽  
Private Insurance ◽  
Cox Proportional Hazards ◽  
Socioeconomic Disparities ◽  
Clinical Predictors ◽  
Case Volume ◽  
The Us ◽  
The Impact

e19026 Background: Cancer surgeries performed at high case volume centers (hCVCs) are associated with improved surgical and clinical outcomes. Resectable hepatocellular carcinoma (rHCC) is not common in the US and the impact of surgery at hCVCs has not been well assessed. We analyzed the impact of surgery at hCVCs on survival, and the potential racial and socioeconomic disparities associated with obtaining care at hCVCs. Methods: We collected demographic, diagnostic, treatment, and survival data of 96,215 patients with stage I-III HCC diagnosed between 2004 – 2015 from the National Cancer Database. To estimate the average surgical volume/year, number of reported cases were divided by the number of years the facility was represented in the database. Logistic regression was used to determine the associations between case volume, facility type and the demographic and clinical variables. We assessed demographic and clinical predictors of overall survival (OS) using Cox proportional hazards regression. Results: In total, 10,419 resected HCC patients were included in the analysis. The median age was 64 (18 – 90), 68.4% were male and 69.5% were white. Facilities were divided into quartiles by average number of surgical CV/year: 1st quartile (1Q) 0.08-1.60, 2Q 1.61 – 3.91, 3Q 3.92 – 8.34, and 4Q 8.35 – 45.34. In a multivariate model, improved OS was seen with each increase in quartiles with the highest CVCs (i.e 4Q) HR 0.70 (95% CI 0.63 – 0.77). Treatment at academic centers did not show an OS advantage (HR 0.93; 95% CI 0.86 – 1.01). Factors including black race (OR 0.83; 95% CI 0.75-0.93), age 65+ (OR 0.91; 95% CI 0.82 – 1.00), and living in a metro area with a population of 250,000 – 1 million people (OR 0.68; 95% CI 0.62 – 0.74) were less likely to be associated with treatment at hCVCs. Conversely, Asians/Pacific Islanders (OR 2.28; 95% CI 2.04 – 2.55) and those with private insurance (OR 1.33; 95% CI 1.18– 1.40) or Medicare (OR 1.21; 95% CI 1.05 – 1.38) were more likely to be treated at hCVCs. Conclusions: rHCC is not common in the US and having surgery at hCVCs improves OS. However, racial and socioeconomic disparities exist in receiving care at these hCVCs.

Sign in / Sign up

Export Citation Format

Share Document