Dangers of using "optimal" cutpoints in the evaluation of prognostic factors

Doug Altman: Driving critical appraisal and improvements in the quality of methodological and medical research

Doug Altman was a visionary leader and one of the most influential medical statisticians of the last 40 years. Based on a presentation in the "Invited session in memory of Doug Altman" at the 40th Annual Conference of the International Society for Clinical Biostatistics (ISCB) in Leuven, Belgium and our long-standing collaborations with Doug, we discuss his contributions to regression modeling, reporting, prognosis research, as well as some more general issues while acknowledging that we cannot cover the whole spectrum of Doug's considerable methodological output. His statement "To maximize the benefit to society, you need to not just do research but do it well" should be a driver for all researchers. To improve current and future research, we aim to summarize Doug's messages for these three topics.

Burden of metastatic bone disease measured on 18F-NaF PET/computed tomography studies as a prognostic indicator in patients with medullary thyroid cancer

PURPOSE

The aim of the study was to assess the association between the burden of metastatic bone disease measured on F-NaF PET/computed tomography (CT) studies and the overall survival (OS) of patients with medullary thyroid cancer (MTC).

METHODS

We retrospectively analyzed 31 patients with MTC who performed 18F-NaF PET/CT studies to assess skeletal metastases. The outcomes of the patients (dead or alive) were established based on the last information available on their files. In the studies considered positives for skeletal metastases, the burden of metastatic bone disease was established calculating the fluoride tumor volume (FTV). The FTV was defined using isocontour thresholds based on percentages of maximal standardized uptake values (SUVmax) in the lesions. These percentages varied from lesion to lesion and were established by visual analysis. The patients were divided into three groups as follows: without skeletal metastases (n = 11), with low FTV (≤50 cm; n = 11) and with high FTV (>50cm; n = 9). The Kaplan-Meier curves were used to analyze the OS in the three groups of patients and the log-rank test was used to determine the statistical significance of the difference between the groups.

RESULTS

There were statistically significant differences in the OS between the group with high FTV and the groups of patients with low FTV (P = 0.036) and without skeletal metastases (P = 0.001). There was not a statistically significant difference between the groups of patients with low FTV and without skeletal metastases (P = 0.147).

CONCLUSION

In patients with MTC, the burden of metastatic bone disease is associated with OS.

A novel prognostic score based on systemic inflammatory biomarkers for patients with oral squamous cell carcinoma

OBJECTIVE

To explore the prognostic value of systemic inflammatory biomarkers (albumin/globulin ratio [AGR], neutrophil/lymphocyte ratio [NLR], and platelet/lymphocyte ratio [PLR]) in patients with oral squamous cell carcinoma (OSCC), and further develop a novel prognostic score (AGR-NLR).

METHODS

A large-scale prospective study enrolling 792 eligible patients from December 2002 to June 2018 was carried out at the First Affiliated Hospital of Fujian Medical University. Three multivariate Cox regression models were performed to assess the association of overall survival (OS) with systemic inflammatory biomarkers, quantified by Akaike information criterion (AIC). Then, a novel AGR-NLR score was established and incorporated into a prognostic nomogram.

RESULTS

In the univariate analysis, the increased AGR was associated with a reduced risk of death. Conversely, the higher NLR and PLR, the worse the OS. In the multivariate Cox regression models, AGR and NLR were stably independent prognostic indicators in all models, with Model 2 showing a lowest AIC (AGR: HR = 0.56, 95%CI: 0.41-0.78; NLR: HR = 1.80, 95%CI: 1.07-3.04). Then, a novel AGR-NLR score was established, which showed a more excellent performance than either AGR or NLR alone (area under curve [AUC]: 0.589, 0.559, and 0.556, respectively). The C-index of the nomogram based on AGR-NLR was superior to that of traditional TNM staging system (C-index: 0.658 versus. 0.596, p < .001). Similar results were also showed by decision curve analysis, indicating the nomogram had more positive net benefit compared to TNM staging system.

CONCLUSION

The novel AGR-NLR score is strongly associated with outcome in patients with OSCC and could be serve as a useful tool to accurately predict the OS of OSCC patients.

Tumor-Associated Tertiary Lymphoid Structures: A Cancer Biomarker and a Target for Next-generation Immunotherapy

The different forms of lymphoid organization that coexist in our bodies appeared at distinct time points during the evolution of the animal kingdom. Some of these forms are constitutive, either in fully dedicated organs, such as lymph nodes, or in tissue interfacing with the external environment, such as mucosal-associated lymphoid tissues. Others, known as tertiary lymphoid structures (TLS), are selectively induced in response to inflammation in any peripheral tissues and organs. In this chapter, we discuss the functional interest of each of these lymphoid organizations under different physiopathological conditions. In the context of cancer, recent findings have identified TLS formation as a hallmark of active T- and B-cell immune responses against tumors. TLS are thus a powerful prognostic factor in nearly all solid cancers, which must be taken into account along with the tumor microenvironment. The presence of TLS also predicts the response to immunotherapy including immune checkpoint blockade. With tumor-associated TLS now a key target for the next generation of immunotherapy, this chapter discusses their potential therapeutic manipulations in oncology.

Defining early recurrence in patients with resected primary colorectal carcinoma and its respective risk factors

PURPOSE

There is no evidence-based definition of early recurrence following resection of colorectal cancer. The purpose of this study is to define a point that discriminates between early and late recurrence in patients who have undergone colorectal cancer resection with curative intent and to analyze associated risk factors.

METHODS

A retrospective single-center cohort study was performed at a university hospital recognized as a comprehensive cancer center, specializing in colorectal cancer surgery. Patient data were retrieved from a prospectively maintained institutional database. Included patients underwent resection for primary, non-metastatic colorectal carcinomas with curative intent between 1995 and 2010. Aims of the study were (1) to define the optimal cut-off point of recurrence-free survival based on overall survival using a minimum p value approach and (2) to identify patterns of initial recurrence and putative risk factors for early recurrence using regression models.

RESULTS

Recurrence was diagnosed in 412 of 1893 patients. Statistical analysis suggested that a recurrence-free survival of 16 months could be used to distinguish between early and late recurrence based on overall survival (p < 0.001). Independent risk factors for early recurrence included advanced pT categories (pT3,4/ypT3,4) and positive lymph node status (pN+/ypN+). Early recurrence was independent of site of recurrence and was associated with worse prognosis.

CONCLUSIONS

Recurrence of colorectal carcinoma within 16 months after primary treatment should be labeled as "early." Tumor categories pT3,4/ypT3,4 and positive lymph node status pN+/ypN+ are predictive of early recurrence.

miR-10a as a therapeutic target and predictive biomarker for MDM2 inhibition in acute myeloid leukemia

Pharmacological inhibition of MDM2/4, which activates the critical tumor suppressor p53, has been gaining increasing interest as a strategy for the treatment of acute myeloid leukemia (AML). While clinical trials of MDM2 inhibitors have shown promise, responses have been confined to largely molecularly undefined patients, indicating that new biomarkers and optimized treatment strategies are needed. We previously reported that the microRNA miR-10a is strongly overexpressed in some AML, and demonstrate here that it modulates several key members of the p53/Rb network, including p53 regulator MDM4, Rb regulator RB1CC1, p21 regulator TFAP2C, and p53 itself. The expression of both miR-10a and its downstream targets were strongly predictive of MDM2 inhibitor sensitivity in cell lines, primary AML specimens, and correlated to response in patients treated with both MDM2 inhibitors and cytarabine. Furthermore, miR-10a inhibition induced synergy between MDM2 inhibitor Nutlin-3a and cytarabine in both in vitro and in vivo AML models. Mechanistically this synergism primarily occurs via the p53-mediated activation of cytotoxic apoptosis at the expense of cytoprotective autophagy. Together these findings demonstrate that miR-10a may be useful as both a biomarker to identify patients most likely to respond to cytarabine+MDM2 inhibition and also a druggable target to increase their efficacy.

A Blood-based Assay for Assessment of Tumor Mutational Burden in First-line Metastatic NSCLC Treatment: Results from the MYSTIC Study

PURPOSE

Tumor mutational burden (TMB) has been shown to be predictive of survival benefit in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors. Measuring TMB in the blood (bTMB) using circulating cell-free tumor DNA (ctDNA) offers practical advantages compared with TMB measurement in tissue (tTMB); however, there is a need for validated assays and identification of optimal cutoffs. We describe the analytic validation of a new bTMB algorithm and its clinical utility using data from the phase III MYSTIC trial.

PATIENTS AND METHODS

The dataset used for the clinical validation was from MYSTIC, which evaluated first-line durvalumab (anti-PD-L1 antibody) ± tremelimumab (anticytotoxic T-lymphocyte-associated antigen-4 antibody) or chemotherapy for metastatic NSCLC. bTMB and tTMB were evaluated using the GuardantOMNI and FoundationOne CDx assays, respectively. A Cox proportional hazards model and minimal P value cross-validation approach were used to identify the optimal bTMB cutoff.

RESULTS

In MYSTIC, somatic mutations could be detected in ctDNA extracted from plasma samples in a majority of patients, allowing subsequent calculation of bTMB. The success rate for obtaining valid TMB scores was higher for bTMB (809/1,001; 81%) than for tTMB (460/735; 63%). Minimal P value cross-validation analysis confirmed the selection of bTMB ≥20 mutations per megabase (mut/Mb) as the optimal cutoff for clinical benefit with durvalumab + tremelimumab.

CONCLUSIONS

Our study demonstrates the feasibility, accuracy, and reproducibility of the GuardantOMNI ctDNA platform for quantifying bTMB from plasma samples. Using the new bTMB algorithm and an optimal bTMB cutoff of ≥20 mut/Mb, high bTMB was predictive of clinical benefit with durvalumab + tremelimumab versus chemotherapy.

Optimal Tricuspid Annular Size for Tricuspid Annuloplasty in Patients with Less-Than-Moderate Functional Tricuspid Regurgitation

Background

We evaluated the association between tricuspid annular dilatation and the development of moderate or severe tricuspid regurgitation (TR). Additionally, we determined the optimal tricuspid annular dilatation threshold to use as an indicator for tricuspid annuloplasty in patients with less-than-moderate functional TR (FTR).

Methods

Between August 2007 and December 2014, 227 patients with less-than-moderate TR underwent mitral valve surgery without a tricuspid valve (TV) procedure. The TV annular diameter was measured via transthoracic echocardiography. The TV annular index (TVAI) was calculated as the TV annular diameter divided by the body surface area. The mean duration of echocardiographic follow-up was 42.0 months (interquartile range, 9.3–66.6 months).

Results

Eight patients (3.5%) developed moderate or severe TR. The rate of freedom from development of moderate or severe TR at 5 years was 96.2%. TV annular diameter, left atrial diameter, preoperative atrial fibrillation, and TVAI were found to be associated with the development of moderate or severe TR in the univariate analysis. A cut-off TVAI value of 19.8 mm/m² was found to predict the development of moderate or severe TR, and a significant difference was observed in the development of TR of this severity based on this cut-off (p<0.001).

Conclusion

The progression of TR was not infrequent in patients with untreated less- than-moderate FTR. An aggressive treatment approach can be helpful to prevent the progression of FTR for patients with risk factors, especially TVAI greater than 19.8 mm/m².

Is FDG-PET texture analysis related to intratumor biological heterogeneity in lung cancer?

OBJECTIVES

We aimed at investigating the origin of the correlations between tumor volume and ¹⁸F-FDG-PET texture indices in lung cancer.

METHODS

Eighty-five consecutive patients with newly diagnosed non-small cell lung cancer (NSCLC) underwent a ¹⁸F-FDG-PET/CT scan before treatment. Seven phantom spheres uniformly filled with ¹⁸F-FDG, and covering a range of activities and volumes similar to that found in lung tumors, were also scanned. Established texture indices were computed for lung tumors and homogeneous spheres. The dependence between textural indices and volume in homogeneous spheres was modeled and then used to predict texture indices in lung tumors. Correlation analyses were carried out between predicted and texture features measured in lung tumors. Cox proportional hazards regression was used to investigate the associations between overall survival and volume-adjusted textural features.

RESULTS

All textural features showed strong, non-linear correlations with volume, both in tumors and homogeneous spheres. Correlations between predicted versus measured texture features were very high for contrast (r² = 0.91), dissimilarity (r² = 0.90), ZP (r² = 0.90), GLNN (r² = 0.86), and homogeneity (r² = 0.82); high for entropy (r² = 0.50) and HILAE (r² = 0.53); and low for energy (r² = 0.30). Cox regressions showed that among volume-adjusted features, only HILAE was associated with overall survival (b = - 0.35, p = 0.008).

CONCLUSION

We have shown that texture indices previously found to be correlated with a number of clinically relevant outcomes might not provide independent information apart from that driven by their correlation with tumor volume, suggesting that these metrics might not be suitable as intratumor heterogeneity markers.

KEY POINTS

• Associations between texture FDG-PET indices and overall survival have been widely reported in lung cancer, with tumor volume also being associated with overall survival, and therefore, it is still unclear whether the predictive power of textural indices is simply driven by this correlation. • Our results demonstrated strong non-linear correlations between textural indices and volume, showing an analogous behavior for lung tumors from patients and homogeneous spheres inserted in phantoms. • Our findings showed that texture FDG-PET indices might not provide independent information apart from that driven by their correlation with tumor volume.

Deficiency of malate-aspartate shuttle component SLC25A12 induces pulmonary metastasis

BACKGROUND

Aspartate biosynthesis and its delivery to the cytosol can be crucial for tumor growth in vivo. However, the impact of intracellular aspartate levels on metastasis has not been studied. We previously described that loss-of-aspartate glutamate carrier 1 (SLC25A12 or AGC1), an important component of the malate-aspartate shuttle, impairs cytosolic aspartate levels, NAD⁺/NADH ratio, mitochondrial respiration, and tumor growth. Here, we report the impact of AGC1-knockdown on metastasis.

RESULTS

Low AGC1 expression correlates with worse patient prognosis in many cancers. AGC1-knockdown in mouse lung carcinoma and melanoma cell lines leads to increased pulmonary metastasis following subcutaneous or intravenous injections, respectively. On the other hand, conventional in vitro metastasis assays show no indication of increased metastasis capacity of AGC1-knockdown cells.

CONCLUSION

This study highlights that certain branches of metabolism impact tumor growth and tumor metastasis differently. In addition, it also argues that commonly known metastasis indicators, including EMT genes, cell migration, or colony formation, do not always reflect metastatic capacity in vivo.

Cellular and gene signatures of tumor-infiltrating dendritic cells and natural-killer cells predict prognosis of neuroblastoma

Tumor-infiltrating lymphocytes play an essential role in improving clinical outcome of neuroblastoma (NB) patients, but their relationship with other tumor-infiltrating immune cells in the T cell-inflamed tumors remains poorly investigated. Here we show that dendritic cells (DCs) and natural killer (NK) cells are positively correlated with T-cell infiltration in human NB, both at transcriptional and protein levels, and associate with a favorable prognosis. Multiplex imaging displays DC/NK/T cell conjugates in the tumor microenvironment of low-risk NB. Remarkably, this connection is further strengthened by the identification of gene signatures related to DCs and NK cells able to predict survival of NB patients and strongly correlate with the expression of PD-1 and PD-L1. In summary, our findings unveil a key prognostic role of DCs and NK cells and indicate their related gene signatures as promising tools for the identification of clinical biomarkers to better define risk stratification and survival of NB patients.

Tumour-infiltrating lymphocytes play a crucial role in neuroblastoma, but their relationship to other immune cells is poorly understood. Here the authors identify the cellular and gene signatures of intratumoural dendritic cells and natural killer cells that predict the clinical outcome of neuroblastoma.

Ten-year fracture risk predicted by proximal femur Hounsfield units

Colon cancer screening occurs at younger ages than osteoporosis screening. Bone density measurements using virtual colonoscopy performed for colon cancer screening can provide an early warning sign of patients at potential risk for osteoporosis-related fractures. Earlier identification may improve treatment and potentially fracture prevention.

INTRODUCTION

Opportunistic osteoporosis screening with computed tomography colonography (CTC) offers an opportunity to capitalize on earlier colorectal cancer screening to identify patients at risk of future fractures. The purpose of this study is to evaluate 10-year fracture and specifically hip fracture risk based on Hounsfield units (HU) obtained from CTC.

METHODS

We identified all CTC scans between 2004 and 2007 of patients 40 years and older with 10 years minimum follow-up. Hounsfield units were measured within the proximal femur and fractures identified via worldwide military records. Patients were stratified into two cohorts based on the presence or lack of a fracture in the wrist, spine, hip, or proximal humerus. Hounsfield unit measurements were compared between groups using Student's t test and the HU threshold was calculated that best approximated an 80% sensitivity to optimally screen patients for fracture risk. The odds ratio, negative predictive value, 10-year incidence of fracture, and survival curves were calculated.

RESULTS

We identified 3711 patients with 183 fractures over 10 years. The HU threshold that corresponded with an 80% sensitivity to identify fractures was 112 HU. The negative predictive value (NPV) for overall fractures and hip fractures was over 97%. The 10-year fracture incidence was higher in patients below 112 HU compared to those above for both overall fractures (6.3% vs 1.7%) and hip fractures (2.7% vs 0.07%). The 112 HU threshold corresponds with an odds ratio for overall fracture and hip fractures of 2.5 (95% confidence interval (CI), 1.7-3.6) and 24.5 (95% CI, 3.3-175.5), respectively.

CONCLUSION

In the 10 years following CTC, patients who experienced a fracture had lower hip HU. Decreasing HU on CTC may be an early warning sign of fracture potential.

Development and Validation of a 6-miRNA Prognostic Signature in Spinal Chordoma

BACKGROUND

Published data have suggested a critical role for microRNA (miRNA) expression in chordoma progression. However, most of these studies focus on single miRNA and no multi-miRNA prognostic signature has been currently established for chordoma. In this study, we sought to develop and validate a 6-miRNA risk score (miRscore) model for survival prediction.

METHODS

Medline, Embase, and Google scholar searches (from inception to July 20, 2018) were conducted to identify candidate miRNAs with prognostic value as per predefined criteria. Quantitative RT-PCR was used to measure miRNA levels in 114 spinal chordoma (54 in the training and 60 in the validation cohort) and 20 control specimens. Subsequently, the miRscore was built based on miRNAs data.

RESULTS

Literature searches identified six prognostic miRNAs (miR-574-3p, miR-1237-3p, miR-140-3p, miR-1, miR-155, and miR-1290) with differential expression in tumor tissues. Bioinformatical analysis revealed an important regulatory role for miR-574-3p/EGFR signaling in chordoma and showed that the target genes of these prognostic miRNAs were mainly enriched in transcription regulation, protein binding and cancer-related pathways. In both cohorts, the miRscore was associated with surrounding muscle invasion by tumor and/or other aggressive features. The miRscore model well predicted local recurrence-free survival and overall survival, which remained after adjusting for other relevant covariates. Further time-dependent receiver operating characteristics analysis in the two cohorts found that the miRscore classifier had stronger prognostic power than known clinical predictors and improved the ability of Enneking staging to predict outcomes. Importantly, recursive-partitioning analysis of both samples combined separated patients into four prognostically distinct risk subgroups for recurrence and survival (both P < 0.001).

CONCLUSIONS

These data suggest the miRscore as a useful prognostic stratification tool in spinal chordoma and may represent an important step toward future personalized treatment of patients.

Management Practices Associated With Prevalence of Lameness in Lambs in 2012-2013 in 1,271 English Sheep Flocks

The evidence base for management practices associated with low prevalence of lameness in ewes is robust. Current best practice is prompt treatment of even mildly lame sheep with parenteral and topical antibiotics with no routine or therapeutic foot trimming and avoiding routine footbathing. To date, comparatively little is known about management of lameness in lambs. Data came from a questionnaire completed by 1,271 English sheep farmers in 2013. Latent class (LC) analyses were used to investigate associations between treatment of footrot and geometric mean flock prevalence of lameness (GMPL) in lambs and ewes, with multinomial models used to investigate effects of flock management with treatment. Different flock typologies were identified for ewes and lambs. In both ewe and lamb models, there was an LC (1) with GMPL <2%, where infectious causes of lameness were rare, and farmers rarely treated lame animals. There was a second LC in ewes only (GMPL 3.2%) where infectious causes of lameness were present but farmers followed "best practice" and apparently controlled lameness. In other typologies, farmers did not use best practice and had higher GMPL than LC1 (3.9-4.2% and 2.8-3.5%, respectively). In the multinomial model, farmers were more likely to use parenteral antibiotics to treat lambs when more than 2-5% of lambs were lame compared with ≤2%. Once >10% of lambs were lame, while farmers were likely to use parenteral antibiotics, only sheep with locomotion score >2 were considered lame, leaving lame sheep untreated, potentially allowing spread of footrot. These farmers also used poor practices of routine foot trimming and footbathing, delayed culling, and poor biosecurity. We conclude there are no managements beneficial to manage lameness in lambs different from those for ewes; however, currently lameness in lambs is not treated using "best practice." In flocks with <2% prevalence of all lameness, where infectious causes of lameness were rare, farmers rarely treated lame animals but also did not practice poor managements of routine foot trimming or footbathing. If more farmers adopted "best practice" in ewes and lambs, the prevalence of lameness in lambs could be reduced to <2%, antibiotic use would be reduced, and sheep welfare would be improved.

IL2RA Promotes Aggressiveness and Stem Cell-Related Properties of Acute Myeloid Leukemia

Overexpression of IL2RA, which encodes the alpha chain of the IL2 receptor, is associated with chemotherapy resistance and poor outcome in acute myeloid leukemia (AML). The clinical potential of anti-IL2RA therapy is, therefore, being explored in early-stage clinical trials. Notwithstanding, only very limited information regarding the biological function of IL2RA in AML is available. Using genetic manipulation of IL2RA expression as well as antibody-mediated inhibition of IL2RA in human cell lines, mouse models, and primary patient samples, we investigated the effects of IL2RA on AML cell proliferation and apoptosis, and on pertinent signaling pathways. The impact of IL2RA on the properties of leukemic stem cells (LSC) and on leukemogenesis were queried. IL2RA promoted proliferation and cell-cycle activity and inhibited apoptosis in human AML cell lines and primary cells. These phenotypes were accompanied by corresponding alterations in cell-cycle machinery and in pathways associated with cell survival and apoptosis. The biological roles of IL2RA were confirmed in two genetically distinct AML mouse models, revealing that IL2RA inhibits differentiation, promotes stem cell-related properties, and is required for leukemogenesis. IL2RA antibodies inhibited leukemic, but not normal, hematopoietic cells and synergized with other antileukemic agents in this regard. Collectively, these data show for the first time that IL2RA plays key biological roles in AML and underscore its value as a potential therapeutic target in this disease. SIGNIFICANCE: This study identifies IL2RA as a potential therapeutic target in AML, where it is shown to regulate proliferation, differentiation, apoptosis, stem cell-related properties, and leukemogenesis.

[How complete is the Germany-wide standardised medication list ("Bundeseinheitlicher Medikationsplan")? An analysis at hospital admission.]

Einleitung  Bei stationärer Aufnahme scheint die Aktualität und Vollständigkeit des Bundeseinheitlichen Medikationsplans häufig nicht gegeben. Ebenso ist unklar, welche Charakteristiken der Pläne die Wahrscheinlichkeit für Diskrepanzen erhöhen.

Methoden  Retrospektiv wurden deshalb 100 Pläne, die zur Arzneimittelanamnese elektiver Patienten einer chirurgischen Klinik mitgebracht wurden, geprüft, ob und welche Abweichungen bestanden. Die Abweichungen wurden 7 Kategorien zugeordnet: Arzneimittel, das in der Anamnese erfasst wurde, fehlt auf dem Plan, Arzneimittel auf dem Plan wird nicht mehr eingenommen, Stärke oder Dosierung fehlt auf dem Plan bzw. ist falsch oder die Darreichungsform ist falsch dokumentiert. Hinweise zur Arzneimitteltherapiesicherheit, involvierte Arzneimittel und -formen wurden ebenfalls erfasst. Mithilfe multivariater Analysen wurde der Einfluss der Aktualität, der Anzahl der Arzneimittel und der ausstellenden Facharztdisziplin der Pläne auf die Art und Anzahl an Diskrepanzen untersucht.

Ergebnisse  Zur Arzneimittelanamnese wiesen 78 % (78/100) der Pläne Abweichungen auf. Insgesamt wurden 226 Abweichungen (2,3 ± 0,6 Abweichungen/Anamnese) dokumentiert. Am häufigsten fehlte ein Arzneimittel auf dem Plan (n = 103). Von allen Hinweisen und Empfehlungen betrafen 64 % (83/177) das perioperative Management von Antithrombotika (n = 55) und Antidiabetika (n = 28). In der multivariaten Analyse stieg nur das Risiko für fehlerhafte Angaben bei Stärke und Dosierung mit dem Alter der Pläne signifikant (p = 0,047) und war um mehr als das 2-fache erhöht, wenn der Plan älter als einen Monat war.

Diskussion  Die Aktualität, Vollständigkeit und Aspekte der Arzneimitteltherapiesicherheit des Bundeseinheitlichen Medikationsplans sollten umfassend und gezielt im Anamnesegespräch validiert werden. In der Praxis sollten Pläne, die älter als 1 Monat sind, besonders kritisch hinsichtlich Angaben zu Stärke und Dosierung geprüft und der Plan entsprechend regelmäßig aktualisiert werden.

Predictors of Intravesical Recurrence After Radical Nephroureterectomy and Prognosis in Patients with Upper Tract Urothelial Carcinoma

Purpose

We investigate factors that may contribute individually to bladder recurrence and find out the potential candidate to receive postoperative single dose intravesical chemotherapy.

Materials and Methods

A total of 217 patients who were diagnosed with upper tract urothelial carcinoma (UTUC) underwent radical nephroureterectomy (RNU) between 2012 and 2016 in a single hospital. The possible risk factors that may contribute to development of bladder recurrence and overall survival were analysed. In order to find out the relationship between 1st bladder recurrence timing and outcome, we divided the 54 of 56 patients (2 patients with prophylactic intravesical chemotherapy excluded) with bladder recurrence after RNU into 2 groups, using the median time of 1st bladder recurrence and confirmed with the “minimum P-value” approach. The primary endpoint was the development of relapsing high-risk non-muscle invasive bladder cancer (NMIBC). The predictive factors of early recurrence and prognostic factors of survival were also analysed.

Results

Among 217 patients with UTUC under RNU, intravesical recurrence occurred in 56 (25.8%) patients after a median follow-up of 35.2 (1.18–83.34) months. On multivariable analysis, the preoperative ureter manipulation (p=0.009) was a significant predictor for the development of bladder tumours. As for overall survival, renal rein invasion (p=0.017), neutrophil to lymphocyte ratio (p=0.021), and main tumour size (p=0.015) were significant predictors. For 54 patients who developed bladder recurrence, the optimal cut-off point of early recurrence was determined to be 10 months after surgery (p=0.042). Preoperative ureter manipulation (p=0.005) and tumour located both pelvicalyceally and ureterically (P=0.042) were identified as independent factors associated with early recurrence. An end-stage renal disease history and surgical margin positive patient has more late bladder recurrence.

Conclusion

Bladder recurrence was common in UTUC after RNU. Early bladder recurrence was associated with more relapsing high-risk NMIBC and preoperative ureter manipulation was identified as an independent factor associated with early recurrence.

A prognostic gene model of immune cell infiltration in diffuse large B-cell lymphoma

Background

Immune cells in the tumor microenvironment are an important prognostic indicator in diffuse large B-cell lymphoma (DLBCL). However, information on the heterogeneity and risk stratification of these cells is limited. We sought to develop a novel immune model to evaluate the prognostic intra-tumoral immune landscape of patients with DLBCL.

Methods

The ESTIMATE and CIBERSORT algorithms were used to estimate the numbers of 22 infiltrating immune cells based on the gene expression profiles of 229 patients with DLBCL who were recruited from a public database. The least absolute shrinkage and selection operator (Lasso) penalized regression analyses and nomogram model were used to construct and evaluate the prognostic immunoscore (PIS) model for overall survival prediction. An immune gene prognostic score (IGPS) was generated by Gene Set Enrichment Analysis (GSEA) and Cox regression analysis was and validated in an independent NCBI GEO dataset (GSE10846).

Results

A higher proportion of activated natural killer cells was associated with a poor outcome. A total of five immune cells were selected in the Lasso model and DLBCL patients with high PIS showed a poor prognosis (hazard ratio (HR) 2.16; 95% CI [1.33-3.50]; P = 0.002). Differences in immunoscores and their related outcomes were attributed to eight specific immune genes involved in the cytokine-cytokine receptor interaction and chemokine signaling pathways. The IGPS based on a weighted formula of eight genes is an independent prognostic factor (HR: 2.14, 95% CI [1.40-3.28]), with high specificity and sensitivity in the validation dataset.

Conclusions

Our findings showed that a PIS model based on immune cells is associated with the prognosis of DLBCL. We developed a novel immune-related gene-signature model associated with the PIS model and enhanced the prognostic functionality for the prediction of overall survival in patients with DLBCL.

Decisive evidence corroborates a null relationship between MTHFR C677T and chronic kidney disease: A case-control study and a meta-analysis

BACKGROUND

Previous meta-analyses have explored the association between the C677T polymorphism of methyltetrahydrofolate reductase (MTHFR) and chronic kidney disease (CKD) but there were no studies with a decisive conclusion. Furthermore, the high heterogeneity among different populations is not yet interpreted.

OBJECTIVES

This study used trial sequential analysis (TSA) to evaluate whether the nowadays conclusion supported by current cumulative samples. We also applied case-weighted meta-regression to explore the potential gene-environment interactions.

METHODS

For the first stage of this study we conducted a case-control study involving 847 dialysis patients from 7 hemodialysis centers in Taipei during 2015 to 2018 and 755 normal controls from a health center in the Tri-Service General Hospital. The second stage combined the results from the first stage with previous studies. The previous studies were collected from PubMed, EMBASE, and Web of Science databases before January 2018.

RESULTS

From the case-control study, the T allele of MTHFR C677T appeared to have a protective effect on end-stage renal disease compared with the C allele [odds ratio (OR): 0.80, 95% CI (confidence interval) = 0.69-0.93]. However, the meta-analysis contradicted the results in Asian (OR = 1.12, 95% CI = 0.96-1.30). The same analysis was also applied in Caucasian and presented similar results from Asian (OR = 1.18, 95% CI = 0.98-1.42). The TSA showed our case-control study to be the decisive sample leading to a null association among Asian population. The high heterogeneity (I = 75%) could explain the contradictory results between the case-control study and the meta-analysis. However, further case-weighted meta-regression did not find any significant interaction between measured factors and MTHFR C677T on CKD.

CONCLUSIONS

High heterogeneities were found in both Caucasian and Asian, which caused the null relationship in meta-analysis while there were significant effects in individual studies. Future studies should further explore the high heterogeneity that might be hidden in unmeasured gene-environment interactions, to explain the diverse findings among different populations.

Videogame-related experiences among regular adolescent gamers

The objective of this study was to identify the videogame-related experiences expressed by regular adolescent gamers and to explore the socio-family factors related to these experiences. A cross-sectional observational and descriptive study was carried out with a convenience sample of regular Spanish videogamers between 16 and 18 years old. To measure the use of videogames for evasion and its negative consequences, the Questionnaire of Videogame-Related Experiences (Cuestionario de Experiencias Relacionadas con Videojuegos, CERV) was used and socio-family variables collected, evaluating their relationship with the results of the CERV. A total of 206 adolescents participated, 89.3% men [84.3-93.2] and 17.9% [12.9-23.9] allocating more than 35 hours a week to videogames. The CERV subscale related to the evasive use of videogames (max. = 24 points) obtained a mean value of 11.71 (SD = 3.52) and the mean value for the subscale related to the negative consequences (max. = 27 points) was 7.14 (SD = 3.33). A higher frequency of high values of evasive use (p = .038) and higher scores of this subscale (p = .02) were found in gamers without brothers or sisters. Higher scores and larger numbers of negative consequences were found in gamers who play more than 21 hours a week (p = .032). In conclusion, frequent use of videogames does not seem to be carried out with an evasive purpose, except in the case of absence of siblings. Frequent videogame use has only proven to carry a higher level of negative consequences when playing more than 21 hours a week. No other socio-family variables related to these subscales of the CERV have been identified.

The Ki-67 Proliferation Index as a Marker of Time to Recurrence in Intracranial Meningioma

BACKGROUND

There are examples of incongruence between the WHO grade and clinical course in meningioma patients. This incongruence between WHO grade and recurrence has led to search for other prognostic histological markers.

OBJECTIVE

To study the correlation between the Ki-67 proliferative index (PI), risk of recurrence, and recurrence rates in meningioma patients.

METHODS

We prospectively collected pathological diagnosis of de novo consecutive meningiomas. In total, we followed 159 patients with clinical controls until recurrence, death, or emigration. We estimated the correlation between risk of recurrence and Ki-67 PI when adjusted for age at diagnosis, sex, WHO grade, extent of surgical resection, and tumor location. We estimated the cumulative incidence of recurrence when considering death without recurrence a competing risk. We report recurrence rates per 100 person-years.

RESULTS

A 1%-point increase of Ki-67 PI yielded a hazard ratio of 1.12 (95% CI: 1.01-1.24) in a multivariate analysis. The cumulative incidence of recurrence was 3% for Ki-67 0% to 4% vs 19% for Ki-67 > 4% meningiomas after 1 yr, but 24% vs 35%, respectively, after 10 yr. There was no significant difference in mean Ki-67 PI between nonrecurrent and recurrent meningioma in a 2-sample t-test (P = .08). The strongest relationship was detected between Ki-67 PI and time to recurrence: Ki-67 < 4% meningiomas recurred after median 4.8 yr, compared to 0.60 to 0.75 yr for patients with higher Ki-67 PI.

CONCLUSION

Ki-67 PI was a marker for time to recurrence rather than a predictor of recurrence. Ki-67 PI may be utilized for patient tailored follow-up.

The Automated Bone Scan Index as a Predictor of Response to Prostate Radiotherapy in Men with Newly Diagnosed Metastatic Prostate Cancer: An Exploratory Analysis of STAMPEDE's "M1|RT Comparison"

Background

Prostate radiotherapy (RT) is a first-line option for newly diagnosed men with low-burden metastatic prostate cancer. The current criterion to define this clinical state is based on manual bone metastasis counts, but enumeration of bone metastases is limited by interobserver variations, and it does not account for metastasis volume or lesional coalescence. The automated bone scan index (aBSI) is a quantitative method of evaluating bone metastatic burden in a standardised and reproducible manner.

Objective

To evaluate whether aBSI has utility as a predictive imaging biomarker to define a newly diagnosed metastatic prostate cancer population that might benefit from the addition of prostate RT to standard of care (SOC) systemic therapy.

Design, setting, and participants

This is an exploratory analysis of men with newly diagnosed metastatic prostate cancer randomised in a 1:1 ratio to either SOC or SOC + prostate RT within the STAMPEDE “M1|RT comparison”.

Intervention

The SOC was lifelong androgen deprivation therapy, with up-front docetaxel permitted from December 2015. Men allocated RT received either a daily or a weekly schedule that was nominated before randomisation.

Outcome measurements and statistical analysis

Baseline bone scans were evaluated retrospectively to calculate aBSI. We used overall (OS) and failure-free (FFS) survival as the end points. Treatment-aBSI interaction was evaluated using the multivariable fractional polynomial interaction (MFPI) and subpopulation treatment effect pattern plot. Further analysis was done in aBSI quartiles using Cox regression models adjusted for stratification factors.

Results and limitations

: Baseline bone scans for 660 (SOC: 323 and SOC + RT: 337) of 2061 men randomised within the “M1|RT comparison” met the software requirements for aBSI calculation. The median age was 68 yr, median PSA was 100 ng/mL, median aBSI was 0.9, and median follow-up was 39 mo. Baseline patient characteristics including aBSI were balanced between the treatment groups. Using the MFPI procedure, there was evidence of aBSI-treatment interaction for OS (p = 0.04, MFPI procedure) and FFS (p <  0.01, MFPI procedure). Graphical evaluation of estimated treatment effect plots showed that the OS and FFS benefit from prostate RT was greatest in patients with a low aBSI. Further analysis in quartiles based on aBSI supported this finding.

Conclusions

A low automated bone scan index is predictive of survival benefit associated with prostate RT in men with newly diagnosed metastatic prostate cancer.

Patient summary

The widely used bone scan can be evaluated using an automated technique to potentially select men with newly diagnosed metastatic prostate cancer who might benefit from prostate radiotherapy.

A Validated T Cell Radiomics Score Is Associated With Clinical Outcomes Following Multisite SBRT and Pembrolizumab

PURPOSE

Combining immune checkpoint blockade (ICB) with stereotactic body radiation therapy (SBRT) may improve the local response to radiation and the systemic response to immunotherapy. However, no prognostic markers exist to identify patients likely to benefit from combined therapy. The degree of T cell-mediated immunity, which can be quantified with radiomics using computed tomography (CT) imaging, is predictive of immunotherapy response. Herein we investigated whether a validated T cell radiomics score (RS) is correlated with clinical outcomes after multisite SBRT and pembrolizumab (SBRT + P).

METHODS AND MATERIALS

The RS was quantified for 68 patients with metastatic treatment-refractory adult solid tumors who received SBRT (30-50 Gy, 3-5 fractions) and pembrolizumab ≤7 days after SBRT. RS was calculated using 8 variables, including 5 radiomics features extracted from pretreatment CT scans. At a prespecified cutoff of the 25th percentile, we assessed the association between RS and clinical outcomes. The Kaplan-Meier method was used to estimate survival outcomes. The prognostic effect of RS was assessed via logistic regression or Cox proportional hazards models. In an exploratory analysis, RS was also analyzed as a continuous variable.

RESULTS

One hundred thirty-nine tumors were analyzed. At the 25th percentile cutoff, high-RS patients were more likely to exhibit irradiated tumor responses to SBRT + P (odds ratio [OR] 10.2; 95% confidence interval [CI], 1.76-59.17; P = .012). High-RS was associated with improved TMC compared with low-RS tumors (hazard ratio [HR] 0.18; 95% CI, 0.04-0.74; P = .018). Furthermore, high-RS patients had improved PFS (HR 0.47, 95% CI, 0.26-0.85; P = .013) and OS (HR 0.39, 95% CI, 0.20-0.75; P = .005). As a continuous variable, higher RS was associated with improved PFS (HR 0.12, 95% CI, 0.03-0.51; P = .004) but did not reach statistical significance for TMC (HR 0.36, 95% CI, 0.02-7.02; P = .502) or OS (HR 0.28, 95% CI, 0.05-1.55; P = .144).

CONCLUSIONS

We demonstrated the clinical validity of RS (at the 25th percentile cutoff) as a prognostic biomarker in patients treated with SBRT + P. Future validation of the prognostic value of RS in larger similarly treated patient cohorts is warranted.

Stromal reactivity differentially drives tumour cell evolution and prostate cancer progression

Prostate cancer (PCa) progression is a complex eco-evolutionary process driven by the feedback between evolving tumour cell phenotypes and microenvironmentally driven selection. To better understand this relationship, we used a multiscale mathematical model that integrates data from biology and pathology on the microenvironmental regulation of PCa cell behaviour. Our data indicate that the interactions between tumour cells and their environment shape the evolutionary dynamics of PCa cells and explain overall tumour aggressiveness. A key environmental determinant of this aggressiveness is the stromal ecology, which can be either inhibitory, highly reactive (supportive) or non-reactive (neutral). Our results show that stromal ecology correlates directly with tumour growth but inversely modulates tumour evolution. This suggests that aggressive, environmentally independent PCa may be a result of poor stromal ecology, supporting the concept that purely tumour epithelium-centric metrics of aggressiveness may be incomplete and that incorporating markers of stromal ecology would improve prognosis.

CD34+CD38-CD123+ Leukemic Stem Cell Frequency Predicts Outcome in Older Acute Myeloid Leukemia Patients Treated by Intensive Chemotherapy but Not Hypomethylating Agents

The prognostic impact of immunophenotypic CD34⁺CD38⁻CD123⁺ leukemic stem cell (iLSC) frequency at diagnosis has been demonstrated in younger patients treated by intensive chemotherapy, however, this is less clear in older patients. Furthermore, the impact of iLSC in patients treated by hypomethylating agents is unknown. In this single-center study, we prospectively assessed the CD34⁺CD38⁻CD123⁺ iLSC frequency at diagnosis in acute myeloid leukemia (AML) patients aged 60 years or older. In a cohort of 444 patients, the median percentage of iLSC at diagnosis was 4.3%. Significant differences were found between treatment groups with a lower median in the intensive chemotherapy group (0.6%) compared to hypomethylating agents (8.0%) or supportive care (11.1%) (p <0.0001). In the intensive chemotherapy group, the median overall survival was 34.5 months in patients with iLSC ≤0.10% and 14.6 months in patients with >0.10% (p = 0.031). In the multivariate analyses of this group, iLSC frequency was significantly and independently associated with the incidence of relapse, event-free, relapse-free, and overall survival. However, iLSC frequency had no prognostic impact on patients treated by hypomethylating agents. Thus, the iLSC frequency at diagnosis is an independent prognostic factor in older acute myeloid patients treated by intensive chemotherapy but not hypomethylating agents.

Individual participant data meta-analysis to examine interactions between treatment effect and participant-level covariates: Statistical recommendations for conduct and planning

Precision medicine research often searches for treatment‐covariate interactions, which refers to when a treatment effect (eg, measured as a mean difference, odds ratio, hazard ratio) changes across values of a participant‐level covariate (eg, age, gender, biomarker). Single trials do not usually have sufficient power to detect genuine treatment‐covariate interactions, which motivate the sharing of individual participant data (IPD) from multiple trials for meta‐analysis. Here, we provide statistical recommendations for conducting and planning an IPD meta‐analysis of randomized trials to examine treatment‐covariate interactions. For conduct, two‐stage and one‐stage statistical models are described, and we recommend: (i) interactions should be estimated directly, and not by calculating differences in meta‐analysis results for subgroups; (ii) interaction estimates should be based solely on within‐study information; (iii) continuous covariates and outcomes should be analyzed on their continuous scale; (iv) nonlinear relationships should be examined for continuous covariates, using a multivariate meta‐analysis of the trend (eg, using restricted cubic spline functions); and (v) translation of interactions into clinical practice is nontrivial, requiring individualized treatment effect prediction. For planning, we describe first why the decision to initiate an IPD meta‐analysis project should not be based on between‐study heterogeneity in the overall treatment effect; and second, how to calculate the power of a potential IPD meta‐analysis project in advance of IPD collection, conditional on characteristics (eg, number of participants, standard deviation of covariates) of the trials (potentially) promising their IPD. Real IPD meta‐analysis projects are used for illustration throughout.

Clinicopathological and Prognostic Characteristics in Extra-Axial Chordomas: An Integrative Analysis of 86 Cases and Comparison With Axial Chordomas

BACKGROUND

Currently, clinical characteristics and prognostic factors of extra-axial chordoma (EAC) remain poorly understood.

OBJECTIVE

To characterize clinicopathological characteristics in a large EAC cohort and investigate their correlation with survival. We also attempted to compare these outcomes with axial chordoma (AC).

METHODS

Medline and Embase searches (from inception to February 28, 2018) were conducted to identify eligible studies as per predefined criteria. The local database at our center was also retrospectively reviewed to include additional patients.

RESULTS

Forty-three studies from the literature and 86 patients from our local institute were identified, resulting in a total of 86 EAC patients and 75 AC patients for analysis. Overall, EAC had similar characteristics to AC, except for having higher CAM5.2 expression, common lobular growth pattern, and better prognosis. Whereas wide surgical resection was consistently associated with favorable survival in both EAC and AC cohorts on univariate analyses, most parameters showed differential prognostic implications between the 2 groups. Significant prognostic factors for local recurrence-free survival on multivariate analysis included type of surgery in both cohorts and tumor Brachyury expression and adjuvant radiotherapy in AC cohort. Multivariate analysis of overall survival demonstrated that type of surgery, tumor Brachyury expression, and duration of symptoms were significant predictors in the AC cohort, whereas none of the analyzed parameters were predictive of overall survival for the EAC group.

CONCLUSION

These data suggest potentially distinct biological behaviors between EAC and AC and may provide useful information to better understand the prognostic characteristics and improve the outcome prediction of EAC patients.

State of the art in selection of variables and functional forms in multivariable analysis-outstanding issues

BACKGROUND

How to select variables and identify functional forms for continuous variables is a key concern when creating a multivariable model. Ad hoc 'traditional' approaches to variable selection have been in use for at least 50 years. Similarly, methods for determining functional forms for continuous variables were first suggested many years ago. More recently, many alternative approaches to address these two challenges have been proposed, but knowledge of their properties and meaningful comparisons between them are scarce. To define a state of the art and to provide evidence-supported guidance to researchers who have only a basic level of statistical knowledge, many outstanding issues in multivariable modelling remain. Our main aims are to identify and illustrate such gaps in the literature and present them at a moderate technical level to the wide community of practitioners, researchers and students of statistics.

METHODS

We briefly discuss general issues in building descriptive regression models, strategies for variable selection, different ways of choosing functional forms for continuous variables and methods for combining the selection of variables and functions. We discuss two examples, taken from the medical literature, to illustrate problems in the practice of modelling.

RESULTS

Our overview revealed that there is not yet enough evidence on which to base recommendations for the selection of variables and functional forms in multivariable analysis. Such evidence may come from comparisons between alternative methods. In particular, we highlight seven important topics that require further investigation and make suggestions for the direction of further research.

CONCLUSIONS

Selection of variables and of functional forms are important topics in multivariable analysis. To define a state of the art and to provide evidence-supported guidance to researchers who have only a basic level of statistical knowledge, further comparative research is required.

The prognostic value of the neutrophil-to-lymphocyte ratio in patients with testicular cancer

OBJECTIVES

To evaluate the potential prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in testicular cancer.

MATERIALS AND METHODS

80 patients with testicular cancer treated at our institution from 2005 to 2018 were retrospectively reviewed. Age, tumor markers, stage and histotype at final pathology, eventual medical treatment, tumor recurrence and follow-up data were extracted. The NLR was retrospectively calculated from blood tests. Data were analyzed by medians comparison, linear correlation, univariate and multivariate Cox regression and survival curve analysis.

RESULTS

Population's median age was 33 years and median follow-up was 40.5 months. Overall, the median NLR was significantly reduced after orchiectomy (2.2 [1.55-3.09] vs. 1.77 [1.34-2.46], M-W P<0.001). Post-orchiectomy NLR was higher in patients who had disease recurrence (2.51;IQ 1.84-3.74 vs 1.59; IQ 1.10-2.24; M-W P=0.001), regardless of disease's stage: HR=1,85 (95%CI 0,99-3,46) and HR=1,91 (95%CI 0,96-3,78) for stage disease I or stage II, respectively. After stratification of patients by post-orchiectomy NLR (optimal cut-off: 2.255), patients with lower NLR had significantly longer recurrence-free survival (107.7 months [95%CI 97,7-119,2] vs. 57.65 months [95%CI 48,2-81,1], P<0.001). Univariable and multivariable Cox proportional hazard analyses, showed post-orchiectomy NLR, histotype at final pathology and disseminated disease at diagnosis as predictors of recurrence.

CONCLUSION

NLR is a simple and wildly available biomarker. Higher post-orchiectomy NLR was found independently correlated to higher risk of recurrence, regardless of disease stage, which could potentially lead to a worse prognosis.

Risk Stratification Using Multivariable Fractional Polynomials in Diffuse Large B-Cell Lymphoma

The risk stratification of diffuse large B-cell lymphoma (DLBCL) is crucial. The International Prognostic Index, the most commonly used and the traditional risk stratification system, is composed of fixed and artificially dichotomized attributes. We aimed to develop a novel prognostic model that allows the incorporation of up-to-date attributes comprehensively without information loss. We analyzed 204 patients with primary DLBCL who were uniformly treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) from 2007 to 2012 at Asan Medical Center. Using the multivariable fractional polynomial (MFP) method and bootstrap resampling, we selected the variables of significance and the best fitted functional form in fractional polynomials. Age, serum β2-microglobulin, serum lactate dehydrogenase, and BCL2 expression were selected as significant variables in predicting overall survival (OS), while age was excluded in predicting 2-years event-free survival. The prognostic score calculated by the MFP model effectively classifies patients into four risk groups with 5-years OS of 89.91% (low risk), 81.21% (low-intermediate risk), 66.40% (high-intermediate risk), and 37.89% (high risk). We suggest a new prognostic model that is simple and flexible. By using the MFP method, we can incorporate various clinicopathologic factors into a risk stratification system without arbitrary dichotomization.

Statistical significance: p value, 0.05 threshold, and applications to radiomics-reasons for a conservative approach

Here, we summarise the unresolved debate about p value and its dichotomisation. We present the statement of the American Statistical Association against the misuse of statistical significance as well as the proposals to abandon the use of p value and to reduce the significance threshold from 0.05 to 0.005. We highlight reasons for a conservative approach, as clinical research needs dichotomic answers to guide decision-making, in particular in the case of diagnostic imaging and interventional radiology. With a reduced p value threshold, the cost of research could increase while spontaneous research could be reduced. Secondary evidence from systematic reviews/meta-analyses, data sharing, and cost-effective analyses are better ways to mitigate the false discovery rate and lack of reproducibility associated with the use of the 0.05 threshold. Importantly, when reporting p values, authors should always provide the actual value, not only statements of "p < 0.05" or "p ≥ 0.05", because p values give a measure of the degree of data compatibility with the null hypothesis. Notably, radiomics and big data, fuelled by the application of artificial intelligence, involve hundreds/thousands of tested features similarly to other "omics" such as genomics, where a reduction in the significance threshold, based on well-known corrections for multiple testing, has been already adopted.

Patient-related risk factors for unplanned 30-day readmission following total knee arthroplasty: a narrative literature review

Osteoarthritis is a debilitating condition as well as a growing global health problem, and total knee arthroplasty (TKA) is an effective treatment for advanced disease. Unplanned 30-day hospital readmission is an indicator of complications, which is a significant financial burden on healthcare systems. We reviewed the literature to better understand the patient-related factors associated with unplanned 30-day readmission following TKA. MEDLINE and EMBASE were searched for studies reporting on patient-related risk factors for unplanned 30-day readmission following primary or revision TKA for any indication. The impact of specific medical comorbidities on increasing the risk of 30-day readmission following TKA is quite well established. The following comorbidities are strongly associated with readmission: bleeding disorder, diabetes, chronic kidney disease and dialysis, chronic immunosuppressant use and history of cancer. Other significant comorbidities include: dementia; depression; haematological (coagulopathy and anaemia), cardiovascular (atrial fibrillation, cardiovascular disease, coronary artery disease and congestive heart failure), respiratory (chronic obstructive pulmonary disease) and liver diseases; and cerebrovascular accident/transient ischaemic attack (but only in revision TKA patients). The influence of variation in sex, age and body mass index each demonstrate a more complex pattern. A systematic review and meta-analysis is required to quantify the impact of the various patient-related factors on 30-day readmission following TKA. Clinicians can use this information in preoperative decision-making.

Phase I/II intra-patient dose escalation study of vorinostat in children with relapsed solid tumor, lymphoma, or leukemia

Background

Until today, adult and pediatric clinical trials investigating single-agent or combinatorial HDAC inhibitors including vorinostat in solid tumors have largely failed to demonstrate efficacy. These results may in part be explained by data from preclinical models showing significant activity only at higher concentrations compared to those achieved with current dosing regimens. In the current pediatric trial, we applied an intra-patient dose escalation design.

The purpose of this trial was to determine a safe dose recommendation (SDR) of single-agent vorinostat for intra-patient dose escalation, pharmacokinetic analyses (PK), and activity evaluation in children (3–18 years) with relapsed or therapy-refractory malignancies.

Results

A phase I intra-patient dose (de)escalation was performed until individual maximum tolerated dose (MTD). The starting dose was 180 mg/m²/day with weekly dose escalations of 50 mg/m² until DLT/maximum dose. After MTD determination, patients seamlessly continued in phase II with disease assessments every 3 months. PK and plasma cytokine profiles were determined. Fifty of 52 patients received treatment. n = 27/50 (54%) completed the intra-patient (de)escalation and entered phase II. An SDR of 130 mg/m²/day was determined (maximum, 580 mg/m²/day). n = 46/50 (92%) patients experienced treatment-related AEs which were mostly reversible and included thrombocytopenia, fatigue, nausea, diarrhea, anemia, and vomiting. n = 6/50 (12%) had treatment-related SAEs. No treatment-related deaths occurred. Higher dose levels resulted in higher C_max. Five patients achieved prolonged disease control (> 12 months) and showed a higher C_max (> 270 ng/mL) and MTDs. Best overall response (combining PR and SD, no CR observed) rate in phase II was 6/27 (22%) with a median PFS and OS of 5.3 and 22.4 months. Low levels of baseline cytokine expression were significantly correlated with favorable outcome.

Conclusion

An SDR of 130 mg/m²/day for individual dose escalation was determined. Higher drug exposure was associated with responses and long-term disease stabilization with manageable toxicity. Patients with low expression of plasma cytokine levels at baseline were able to tolerate higher doses of vorinostat and benefited from treatment. Baseline cytokine profile is a promising potential predictive biomarker.

Trial registration

ClinicalTrials.gov, NCT01422499. Registered 24 August 2011,

The impact of postoperative inflammation on recurrence in patients with colorectal cancer

BACKGROUND

Systemic inflammatory response is strongly linked to among cancer development, progression and poor prognosis. The aim of this study was to clarify the impact of postoperative serum C-reactive protein (CRP) levels on the prognoses of patients with colorectal cancer (CRC).

METHODS

A total of 467 patients with stage I-III CRC who underwent curative surgery were retrospectively analyzed. To precisely evaluate the effect of postoperative inflammatory status on prognosis in CRC patients, we excluded patients with postoperative complication or elevated preoperative CRP level (CRP > 1.0 mg/dL). Patients were divided into two groups based on their highest post-resection CRP levels (max CRP): the low CRP group (LCG; < 9.0 mg/dL, n = 385) and high CRP group (HCG; ≥ 9.0 mg/dL, n = 82). Furthermore, the effect of inflammation on malignant potential of CRC cells was evaluated using in vitro peritoneal dissemination model.

RESULTS

HCG patients showed significantly worse recurrence-free survival (RFS) than LCG patients (p = 0.012). Multivariate analysis revealed that a higher max CRP was an independent prognostic factor for RFS (HR: 2.07, 95% CI 1.04-3.96, p = 0.038). Concerning the risk factors for high max CRP level, multivariate analysis revealed that older age (p < 0.001), male sex (p < 0.001), higher BMI (p = 0.005), right-sided colorectal cancer (p = 0.008), and longer operative time (p = 0.007) were independent risk factors. A higher max CRP was also significantly associated with peritoneal recurrence (p < 0.001). Additionally, recombinant cytokines enhanced the adhesive ability of CRC cells to mesothelial cell in vitro (p < 0.05).

CONCLUSIONS

Postoperative inflammation may be a possible mechanism portending the poor prognosis of CRC patients.

In silico identification of microRNAs as candidate colorectal cancer biomarkers

The involvement of microRNA in cancers plays a significant role in their pathogenesis. Specific expressions of these non-coding RNAs also serve as biomarkers for early colorectal cancer diagnosis, but their laboratory/molecular identification is challenging and expensive. The aim of this study was to identify potential microRNAs for colorectal cancer diagnosis using in silico approach. Sequence similarity search was employed to obtain the candidate microRNA from the datasets, and three target prediction software were employed to determine their target genes. To determine the involvement of these microRNAs in colorectal cancer, the microRNA gene list obtained was used alongside with colorectal cancer expressed genes from gbCRC and CoReCG databases for gene intersection analysis. The involvement of these genes in the cancer subtype was further strengthened with the DAVID database. KEGG and Gene Ontology were used for the pathway and functional analysis, while STRING was employed for the interactions of protein network and further visualized by Cytoscape. The cBioPortal database was used to prioritize the target genes; prognostic and expression analysis were finally performed on the candidate microRNAs and the prioritized targets. This study, therefore, identified five candidate microRNAs, two hub genes (CTNNB1 and epidermal growth factor receptor), and seven significant target genes associated with colorectal cancer. The molecular validation studies are ongoing to ascertain the biological fitness of these findings.

Validation, clinical utility and limitations of the Amsterdam-Oxford model for primary sclerosing cholangitis

BACKGROUND & AIMS

Recently the Amsterdam-Oxford model (AOM) was introduced as a prognostic model to assess the risk of death and/or liver transplantation (LT) in primary sclerosing cholangitis (PSC). We aimed to validate and assess the utility of the AOM.

METHODS

Clinical and laboratory data were collected from the time of PSC diagnosis until the last visit or time of LT or death. The AOM was calculated at yearly intervals following PSC diagnosis. Discriminatory performance was assessed by calculation of the C-statistic and prediction accuracy by comparing the predicted survival with the observed survival in Kaplan-Meier estimates. A grid search was performed to identify the most discriminatory AOM threshold.

RESULTS

A total of 534 patients with PSC and a mean (SD) age of 39.2 (13.1) years were included. The diagnosis was large duct PSC in 466 (87%), PSC with features of autoimmune hepatitis in 52 (10%) and small-duct PSC in 16 (3%). During the median (IQR) follow-up of 7.8 (4.0-12.6) years, 167 patients underwent LT and 65 died. The median LT-free survival was 13.2 (11.8-14.7) years. The C-statistic of the AOM ranged from 0.67 at baseline to 0.75 at 5 years of follow-up. The difference between the predicted and observed survival ranged from -1.6% at 1 year to + 3.9% at 5 years of follow-up. Patients that developed AOM scores >2.0 were at significant risk of LT or death (time-dependent hazard ratio 4.09; 95% CI 2.99-5.61).

CONCLUSIONS

In this large cohort of patients with PSC, the AOM showed an adequate discriminative performance and good prediction accuracy at PSC diagnosis and during follow-up. This study further validates the AOM as a valuable risk stratification tool in PSC and extends its utility.

LAY SUMMARY

In our study we assessed whether the Amsterdam-Oxford model (AOM) is able to correctly estimate the risk of liver transplantation or death in patients with primary sclerosing cholangitis (PSC). This model uses 7 objective and readily available variables to estimate prognosis for individual patients at the time of PSC diagnosis. The AOM may aid in patient counselling and timing of diagnostic procedures or therapeutic interventions for complications of liver disease. We confirm that the model works well at PSC diagnosis, but also when the AOM is recalculated at different timepoints during follow-up, greatly improving the applicability of the model in clinical practice and for individual patients.

Preoperative total cholesterol-lymphocyte score as a novel immunonutritional predictor of survival in gastric cancer

PURPOSE

Immunonutritional status is a known prognostic correlate in the context of gastric cancer (GC). In the present study, we investigated the prognostic relevance of a lipid profile-based immunonutritional score in patients with GC.

METHODS

Data pertaining to 224 patients with stage II and III GC who underwent curative gastrectomy were retrospectively analyzed. The total cholesterol-lymphocyte score (TL score) was defined as follows: patients with both low total cholesterol (TC) and total lymphocyte count were allocated a score of 2; patients with only one or none of these biochemical abnormalities were allocated a score of 1 or 0, respectively.

RESULTS

Among the serum lipid indices, low TC was the strongest predictor of cancer-specific survival (CSS; p = 0.001). On multivariate analysis, both low prognostic nutritional index (PNI) (p < 0.001) and high TL score (p = 0.003) were independent prognostic factors. PNI was significantly associated with peritoneal recurrence (p = 0.047), while TL score was significantly associated with locoregional and distant metastasis (p = 0.004 and p = 0.003, respectively).

CONCLUSIONS

TL score may facilitate risk stratification of patients based on CSS. TL score plus PNI may help predict the recurrence pattern in patients with stage II and III GC.

Comprehensive biomarker analyses identifies HER2, EGFR, MET RNA expression and thymidylate synthase 5'UTR SNP as predictors of benefit from S-1 adjuvant chemotherapy in Japanese patients with stage II/III gastric cancer

Purpose: A comprehensive molecular analysis was conducted to identify prognostic and predictive markers for adjuvant S-1 chemotherapy in stage II/III Japanese gastric cancer (GC) patients and to evaluate their potential suitability for alternative cytotoxic or targeted drugs.

Experimental Design: We investigated genetic polymorphisms of enzymes potentially involved in 5-fluoruracil (5-FU) metabolism as well as platinum resistance, previously identified genomic subtypes potentially predicting 5-FU benefit, and mRNA expression levels of receptor tyrosine kinases and KRAS as potential treatment targets in a single institution cohort of 252 stage II/III GC patients treated with or without S-1 after D2 gastrectomy.

Results: 88% and 62% GC had a potentially 5-FU sensitive phenotype by SNP analyses of TS 3'UTR, and TS 5'UTR, respectively. 24%, 46%, 40%, 5%, and 44% GC had a potentially platinum sensitive phenotype by SNP analyses of GSTP1, ERCC1 rs11615, ERCC1 rs3212986, ERCC2, and XRCC1, respectively. High HER2, EGFR, FGFR2, or MET mRNA expression was observed in 49%, 66%, 72%, and 54% GC, respectively. High HER2 expression was the only significant prognosticator (HR=3.912, 95%CI: 1.706-8.973, p=0.0005). High HER2 (p=0.031), low EGFR (p=0.124), high MET (p=0.165) RNA expression, and TS 5'UTR subtype 2R/2R, 2R/3C, or 3C (p=0.058) were significant independent predictors for S-1 resistance.

Conclusions: The present study suggests that platinum-based or RTK targeted agents could be alternative treatment options for a substantial subgroup of Japanese GC patients currently treated with S-1. HER2, EGFR, MET, and TS 5'UTR SNP appear to be promising predictive markers for S-1 resistance warranting validation in an independent GC series.

Cubic splines to model relationships between continuous variables and outcomes: a guide for clinicians

SERIES EDITORS' NOTE

We are pleased to add this typescript to the Bone Marrow Transplantation Statistics Series. We realize the term cubic splines may be a bit off-putting to some readers, but stay with us and don't get lost in polynomial equations. What the authors describe is important conceptually and in practice. Have you ever tried to buy a new pair of hiking boots? Getting the correct fit is critical; shoes that are too small or too large will get you in big trouble! Now imagine if hiking shoes came in only 2 sizes, small and large, and your foot size was somewhere in between. You are in trouble. Sailing perhaps?Transplant physicians are often interested in the association between two variables, say pre-transplant measurable residual disease (MRD) test state and an outcome, say cumulative incidence of relapse (CIR). We typically reduce the results of an MRD test to a binary, negative or positive, often defined by an arbitrary cut-point. However, MRD state is a continuous biological variable, and reducing it to a binary discards what may be important, useful data when we try to correlate it with CIR. Put otherwise, we may miss the trees from the forest.Another way to look at splines is a technique to make smooth curves out of irregular data points. Consider, for example, trying to describe the surface of an egg. You could do it with a series of straight lines connecting points on the egg surface but a much better representation would be combining groups of points into curves and then combining the curves. To prove this try drawing an egg using the draw feature in Microsoft Powerpoint; you are making splines.Gauthier and co-workers show us how to use cubic splines to get the maximum information from data points, which may, unkindly, not lend themselves to dichotomization or a best fit line. Please read on. We hope readers will find their typescript interesting and exciting, and that it will give them a new way to think about how to analyse data. And no, a spline is not a bunch of cactus spines. Robert Peter Gale, Imperial College London, and Mei-Jie Zhang, Medical College of Wisconsin and CIBMTR.

Impact of facility type and volume in low-grade glioma outcomes

OBJECTIVE

The object of this study was to investigate the impact of facility type (academic center [AC] vs non-AC) and facility volume (high-volume facility [HVF] vs low-volume facility [LVF]) on low-grade glioma (LGG) outcomes.

METHODS

This retrospective cohort study included 5539 LGG patients (2004-2014) from the National Cancer Database. Patients were categorized by facility type and volume (non-AC vs AC, HVF vs LVF). An HVF was defined as the top 1% of facilities according to the number of annual cases. Outcomes included overall survival, treatment receipt, and postoperative outcomes. Kaplan-Meier and Cox proportional-hazards models were applied. The Heller explained relative risk was computed to assess the relative importance of each survival predictor.

RESULTS

Significant survival advantages were observed at HVFs (HR 0.67, 95% CI 0.55-0.82, p < 0.001) and ACs (HR 0.84, 95% CI 0.73-0.97, p = 0.015), both prior to and after adjusting for all covariates. Tumor resection was 41% and 26% more likely to be performed at HVFs vs LVFs and ACs vs non-ACs, respectively. Chemotherapy was 40% and 88% more frequently to be utilized at HVFs vs LVFs and ACs vs non-ACs, respectively. Prolonged length of stay (LOS) was decreased by 42% and 24% at HVFs and ACs, respectively. After tumor histology, tumor pattern, and codeletion of 1p19q, facility type and surgical procedure were the most important contributors to survival variance. The main findings remained consistent using propensity score matching and multiple imputation.

CONCLUSIONS

This study provides evidence of survival benefits among LGG patients treated at HVFs and ACs. An increased likelihood of undergoing resections, receiving adjuvant therapies, having shorter LOSs, and the multidisciplinary environment typically found at ACs and HVFs are important contributors to the authors' finding.

Frailty Index is Associated with Adverse Outcomes after Aortic Valve Replacement in Elderly Patients

BACKGROUND

This study was conducted to evaluate the prognostic value of the frailty index based on routine laboratory data (FI-L) in elderly patients who underwent surgical aortic valve replacement (SAVR).

METHODS

A total of 154 elderly patients (≥ 75 years) (78.7 ± 3.6 years; men:women = 78:76) who underwent aortic valve replacement with stented bioprosthesis between 2001 and 2018 were enrolled. The FI-L was calculated as the proportion of abnormal results out of 32 items based on laboratory tests, pulse rate and blood pressure. The primary outcome was all-cause mortality. Secondary outcomes included operative mortality and aortic valve-related events (AVREs) during follow-up. The predictive values of FI-L for the early and late outcomes were evaluated using logistic regression and Cox proportional hazards models, respectively. The median follow-up duration was 40 months (interquartile, 15-74).

RESULTS

The operative mortality rate was 3.9% (n = 6). Late death occurred in 29 patients. The overall survival (OS) rates at 5, 10, and 15 years were 83.3%, 59.0%, and 41.6%, respectively. The AVREs occurred in 28 patients and the freedom rates from AVREs at 5, 10, and 15 years were 79.4%, 72.7%, and 52.9%, respectively. Multivariable analyses demonstrated that FI-L was a significant factor for OS (hazard ratio, 1.075; 95% confidence interval, 1.040-1.111). A minimal P value approach showed that a FI-L of 25% was the best cutoff value to predict OS after SAVR.

CONCLUSION

The FI-L is significantly associated with early and long-term outcomes after SAVR in elderly patients. Frailty rather than a patient's age should be considered in the decision-making process for SAVR in elderly patients.

Do early luteal serum progesterone levels predict the reproductive outcomes in IVF with oral dydrogesterone for luteal phase support?

Objective

We sought to determine whether the early luteal serum progesterone (P₄) level predicts the success of IVF treatment with oral dydrogesterone for luteal support.

Method

This retrospective monocentric cohort study included 242 women who underwent IVF treatment with fresh embryo transfer (ET) between July 2017 and June 2018. The population was unselected, and women were treated according to our unit’s usual stimulation protocols. For the luteal phase support (LPS), all women were supplemented with a 10 mg three-times-daily dose of oral dydrogesterone beginning on the day of oocyte pick-up (OPU). Blood sampling was performed on the day of ET (Day 2–3 after OPU) to determine the early luteal serum progesterone level.

Results

ROC curve analysis allowed us to determine two thresholds for the prediction of live birth using the early P₄ level. Women who had early luteal P₄ levels greater than 252 nmol/l had a significantly higher live birth rate (27.1%) than women with early luteal P₄ between 115 and 252 nmol/l (17.2%) and women with early luteal P₄ below 115 nmol/l (6.0%; p = 0.011). After a multiple regression analysis, an early luteal P₄ level greater than 252 nmol/l was still associated with a higher chance of a live birth than a P₄ between 115 and 252 nmol/l (OR = 0.40 [0.18–0.91]; p = 0.028) or a P₄ below 115 nmol/l (OR = 0.10 [0.01–0.52]; p = 0.006).

Conclusions

Our study suggests a positive association between early P₄ levels and reproductive outcomes in IVF using oral dydrogesterone for luteal support. The inconsistencies between our results and those of other studies suggest that extrapolation is impractical. Further larger prospective cohort studies should be conducted to determine reliable thresholds that could be used to personalize luteal phase support.

Uncovering the clinical impact of kallikrein-related peptidase 5 (KLK5) mRNA expression in the colorectal adenoma-carcinoma sequence

Background Kallikrein-related peptidases (KLKs) are a subgroup of serine proteases located on chromosome 19q13.3. Most KLKs have been extensively studied as potential biomarkers for several carcinomas and other diseases. KLK5 was originally identified from a keratinocyte library, and its enzyme was purified from the stratum corneum of human skin. KLK5 was shown to be differentially expressed in a variety of endocrine tumors, although it is not as yet examined widely in colorectal cancer (CRC). Methods In this study, we quantitatively assessed the mRNA expression status of KLK5 in 197 colorectal tissues from 133 patients (70 cancerous and their paired normal colonic mucosa for 64 of them, as well as 63 colorectal adenomas) by quantitative real-time PCR (qPCR) using TaqMan probes. Statistical analysis evaluated the results. Results It was shown that KLK5 expression is reduced following the histologically non-cancerous-adenoma sequence (p<0.001), whereas it is increased during the sequence adenoma-carcinoma (p<0.001). Furthermore, KLK5 positive expression is associated with positive nodal status (p=0.022), advanced tumor stage (p=0.038) and high histological grade (p=0.033). Cox univariate analysis revealed that KLK5 positive expression is associated with disease-free survival (DFS) (p=0.028) and overall survival (OS) of patients (p=0.048). Kaplan-Meyer survival models showed that patients with positive KLK5 expression have lower DFS (p=0.009) and OS (p=0.019). Receiver operating characteristic (ROC) analysis demonstrated for first time that KLK5 expression had significant discriminatory values between cancer and adenoma tissues (area under the curve [AUC] 0.77; 95% confidence interval [CI]=0.69-0.85, p=0.03). Conclusions KLK5 mRNA expression may be useful for the differentiation of CRC from colorectal adenoma and represents a potential unfavorable prognostic biomarker for CRC.

SOCS2 is part of a highly prognostic 4-gene signature in AML and promotes disease aggressiveness

Acute myeloid leukemia (AML) is a heterogeneous disease with respect to its genetic and molecular basis and to patients´ outcome. Clinical, cytogenetic, and mutational data are used to classify patients into risk groups with different survival, however, within-group heterogeneity is still an issue. Here, we used a robust likelihood-based survival modeling approach and publicly available gene expression data to identify a minimal number of genes whose combined expression values were prognostic of overall survival. The resulting gene expression signature (4-GES) consisted of 4 genes (SOCS2, IL2RA, NPDC1, PHGDH), predicted patient survival as an independent prognostic parameter in several cohorts of AML patients (total, 1272 patients), and further refined prognostication based on the European Leukemia Net classification. An oncogenic role of the top scoring gene in this signature, SOCS2, was investigated using MLL-AF9 and Flt3-ITD/NPM1c driven mouse models of AML. SOCS2 promoted leukemogenesis as well as the abundance, quiescence, and activity of AML stem cells. Overall, the 4-GES represents a highly discriminating prognostic parameter in AML, whose clinical applicability is greatly enhanced by its small number of genes. The newly established role of SOCS2 in leukemia aggressiveness and stemness raises the possibility that the signature might even be exploitable therapeutically.