72 research outputs found

    Higher-Derivative Quantum Cosmology

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    The quantum cosmology of a higher-derivative derivative gravity theory arising from the heterotic string effective action is reviewed. A new type of Wheeler-DeWitt equation is obtained when the dilaton is coupled to the quadratic curvature terms. Techniques for solving the Wheeler-DeWitt equation with appropriate boundary conditions shall be described, and implications for semiclassical theories of inflationary cosmology will be outlined.Comment: 11 pages TeX. A term has been removed from equation (13

    Genomic copy number alterations as biomarkers for triple negative pregnancy-associated breast cancer

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    BACKGROUND: PABC, commonly defined as breast cancer diagnosed during or ≤ 1 year after pregnancy, accounts for 7% of all breast cancers in women ≤ 45 years. Compared to age-matched non-PABC patients, PABC is characterized by a particularly aggressive histopathologic profile with poorly differentiated and estrogen- and progesterone receptor negative tumors and associated high mortality rates. This study assessed the genomic background of triple-negative PABC tumors by detection of copy number alterations (CNAs). METHODS: MLPA was used to compare CNAs in breast cancer-associated chromosomal loci between triple-negative PABC- and subtype-matched non-PABC patients. Both CNA patterns were evaluated by cluster analysis; associations between individual gene CNAs, pathological characteristics and survival were explored. RESULTS: Triple-negative PABC tumors exhibited unique CNAs compared to non-PABC tumors, including enrichment for TOP2A copy number loss, an independent predictor of worse overall survival (HR 8.96, p = 0.020). Cluster analysis based on CNA profiles identified a triple-negative PABC-subgroup with a particularly poor prognosis, characterized by chromosome 8p copy number loss. Individual gene CNAs analysis revealed that FGFR1 copy number loss on chromosome 8p11.23 was an independent predictor of poor outcome in multivariate analysis (HR 3.59, p = 0.053) and predicted the development of distant metastases (p = 0.048). CONCLUSION: This study provides novel insights into the biology of triple-negative PABC tumors suggesting that CNAs, particularly 8p loss and TOP2A loss, are involved in the development of breast cancer during pregnancy. FGFR1 loss and TOP2A loss seem to be promising new biomarkers that independently identify subgroups of PABC patients with poor prognosis. These genomic biomarkers may provide clues for personalized therapy

    From Surviving Cancer to Getting on With Life: Adult Testicular Germ Cell Tumor Survivors' Perspectives on Transition From Follow-Up Care to Long-Term Survivorship

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    With an increasing incidence and a high cure rate, a growing number of testicular germ cell tumor (TGCT) survivors require specialized follow-up care. However, knowledge of these patients' needs is lacking, leaving TGCT survivors with unmet care needs at risk of symptom burden when transitioning to long-term survivorship. This grounded theory study aimed to understand the perspectives of TGCT survivors' transition from follow-up care to long-term survivorship. A total of 12 adult TGCT survivors in follow-up care or completion less than a year were in-depth semi-structured interviewed. Interviews were audiotaped and transcribed verbatim. Transcripts were analyzed by constant comparison, and the core category "Dealing with back-and-forth forces" emerged in the integrated concepts. Two comparative processes in dealing with those forces were identified: the process of Living beyond the sword of Damocles involved the transition from feeling threatened by cancer to overcoming those threats; the process of Getting on with one's life can be described as transitioning from a period where cancer overruled their lives to carrying on with everyday life. The processes toward long-term survivorship follow general characteristics; the transition itself is an individual journey that depends on (life) experiences. The constructed model can guide healthcare professionals and researchers involved in TGCT survivorship to understand TGCT survivors' individual and ensuing needs. When TGCT survivors receive individualized and tailored follow-up care, it can assist in preventing and reducing long-term and late effects on long-term survivorship

    Perspectives and Concerns on Late Effects Regarding Sexuality among Adolescents and Young Adults Treated for Testicular Germ Cell Tumor: The PRICELESS-Study-A Qualitative Study

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    This study aimed to explore perspectives and concerns regarding sexuality among adolescents and young adults (AYAs) possibly experiencing late effects after testicular germ cell tumor (TGCT) treatment. A qualitative study was performed in which semi-structured interviews were held with thirteen AYAs from a center of expertise for TGCT in the Netherlands. Data were analyzed using Braun and Clark's thematic analysis method. Seven interacting and interconnected themes were found: desire to have children, rediscovering sexuality, insecurity about sexual performance, acceptance of physical change, loss of masculinity, burden on relationship, and openness in discussing sexuality. Concerns about the desire to have children seem to play a significant role. In conclusion, TGCT patients face multiple changes (physical, emotional, relational, and sexual), followed by a difficult period of acceptance, after which a new phase of rediscovering sexuality appeared. These findings can help to make healthcare professionals aware of the underlying mechanisms and concerns about sexuality. Furthermore, insights can help to develop sexuality-themed items for a broader monitoring tool to structurally assess the late effects to support discussing sexuality

    Induction therapy with ipilimumab and nivolumab followed by consolidative chemoradiation as organ-sparing treatment in urothelial bladder cancer:study protocol of the INDIBLADE trial

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    Introduction: Studies that assessed the efficacy of pre-operative immune checkpoint blockade (ICB) in locally advanced urothelial cancer of the bladder showed encouraging pathological complete response rates, suggesting that a bladder-sparing approach may be a viable option in a subset of patients. Chemoradiation is an alternative for radical cystectomy with similar oncological outcomes, but is still mainly used in selected patients with organ-confined tumors or patients ineligible to undergo radical cystectomy. We propose to sequentially administer ICB and chemoradiation to patients with (locally advanced) muscle-invasive bladder cancer. Methods: The INDIBLADE trial is an investigator-initiated, single-arm, multicenter phase 2 trial. Fifty patients with cT2-4aN0-2M0 urothelial bladder cancer will be treated with ipilimumab 3 mg/kg on day 1, ipilimumab 3 mg/kg plus nivolumab 1 mg/kg on day 22, and nivolumab 3 mg/kg on day 43 followed by chemoradiation. The primary endpoint is the bladder-intact event-free survival (BI-EFS). Events include: local or distant recurrence, salvage cystectomy, death and switch to platinum-based chemotherapy. We will also evaluate the potential of multiparametric magnetic resonance imaging of the bladder to identify non-responders, and we will assess the clearance of circulating tumor DNA as a biomarker for ICB treatment response. Discussion: This is the first trial in which the efficacy of induction combination ICB followed by chemoradiation is being evaluated to provide bladder-preservation in patients with (locally advanced) urothelial bladder cancer. Clinical Trial Registration: The INDIBLADE trial was registered on clinicaltrials.gov on January 21, 2022 (NCT05200988).</p

    Venous and arterial thrombosis in patients receiving immune checkpoint inhibitors

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    BACKGROUND: Immune checkpoint inhibitors (ICPi) have been associated with a prothrombotic and pro-atherogenic tendency which could lead to an increased risk of thrombosis. The aim of this study was to investigate the incidence of venous and arterial thrombosis (myocardial infarction or ischemic stroke) in patients who used ICPi as compared with the general population. Furthermore, we investigated the association between the occurrence of venous or arterial thrombosis and mortality. METHODS: Patients receiving immune checkpoint inhibitors ICPi between January 1, 2013, and May 31, 2020, at the University Medical Center Utrecht, the Netherlands, were included in this study. Indirect standardization was used to compare the incidence rates of venous and arterial thrombosis in patients who used ICPi to the age- and sex weighted incidence rates in the general population. Time-dependent Cox proportional hazard regression model was used to calculate Hazard ratios (HRs) with 95% CIs to investigate the association between the occurrence of a venous or arterial event after start of an ICPi and mortality. RESULTS: The age- and sex weighted incidence rates in 663 patients who used ICPi as compared to the general population was 22.7-fold (95% CI 16.6-31.0) increased for venous thrombosis, 3.0-fold (95% CI 1.2-7.1) increased for myocardial infarction, and 3.2-fold (95% CI 1.6-5.7) increased for ischemic stroke. After adjustment, the all-cause mortality risk was 2.3-fold (95% CI 1.5-3.5) increased for patients who were diagnosed with venous thrombosis during follow-up and 2.2-fold (95% CI 1.1-4.1) increased for patients who were diagnosed with arterial thrombosis during follow-up as compared with patients without venous or arterial thrombosis during follow-up. CONCLUSION: Patients receiving ICPi have elevated risks of venous thrombosis and arterial thrombosis. Occurrence of venous thrombosis or arterial thrombosis during treatment with ICPi is associated with an increased mortality risk

    Stereotactic Body radiotherapy and pedicLE screw fixatioN During one hospital visit for patients with symptomatic unstable spinal metastases: a randomized trial (BLEND RCT) using the Trials within Cohorts (TwiCs) design

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    BACKGROUND: Spinal metastases can lead to unremitting pain and neurological deficits, which substantially impair daily functioning and quality of life. Patients with unstable spinal metastases receive surgical stabilization followed by palliative radiotherapy as soon as wound healing allows. The time between surgery and radiotherapy delays improvement of mobility, radiotherapy-induced pain relief, local tumor control, and restart of systemic oncological therapy. Stereotactic body radiotherapy (SBRT) enables delivery of preoperative high-dose radiotherapy while dose-sparing the surgical field, allowing stabilizing surgery within only hours. Patients may experience earlier recovery of mobility, regression of pain, and return to systemic oncological therapy. The BLEND RCT evaluates the effectiveness of SBRT followed by surgery within 24 h for the treatment of symptomatic, unstable spinal metastases. METHODS: This phase III randomized controlled trial is embedded within the PRospective Evaluation of interventional StudiEs on boNe meTastases (PRESENT) cohort. Patients with symptomatic, unstable spinal metastases requiring stabilizing surgery and radiotherapy will be randomized (1:1). The intervention group (n = 50) will be offered same-day SBRT and surgery, which they can accept or refuse. According to the Trial within Cohorts (TwiCs) design, the control group (n = 50) will not be informed and receive standard treatment (surgery followed by conventional radiotherapy after 1-2 weeks when wound healing allows). Baseline characteristics and outcome measures will be captured within PRESENT. The primary outcome is physical functioning (EORTC-QLQ-C15-PAL) 4 weeks after start of treatment. Secondary endpoints include pain response, time until return to systemic oncological therapy, quality of life, local tumor control, and adverse events up to 3 months post-treatment. DISCUSSION: The BLEND RCT evaluates the effect of same-day SBRT and stabilizing surgery for the treatment of symptomatic, unstable spinal metastases compared with standard of care. We expect better functional outcomes, faster pain relief, and continuation of systemic oncological therapy. The TwiCs design enables efficient recruitment within an ongoing cohort, as well as prevention of disappointment bias and drop-out as control patients will not be informed about the trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT05575323. Registered on October 11, 2022

    Induction therapy with ipilimumab and nivolumab followed by consolidative chemoradiation as organ-sparing treatment in urothelial bladder cancer: study protocol of the INDIBLADE trial

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    Introduction: Studies that assessed the efficacy of pre-operative immune checkpoint blockade (ICB) in locally advanced urothelial cancer of the bladder showed encouraging pathological complete response rates, suggesting that a bladder-sparing approach may be a viable option in a subset of patients. Chemoradiation is an alternative for radical cystectomy with similar oncological outcomes, but is still mainly used in selected patients with organ-confined tumors or patients ineligible to undergo radical cystectomy. We propose to sequentially administer ICB and chemoradiation to patients with (locally advanced) muscle-invasive bladder cancer. Methods: The INDIBLADE trial is an investigator-initiated, single-arm, multicenter phase 2 trial. Fifty patients with cT2-4aN0-2M0 urothelial bladder cancer will be treated with ipilimumab 3 mg/kg on day 1, ipilimumab 3 mg/kg plus nivolumab 1 mg/kg on day 22, and nivolumab 3 mg/kg on day 43 followed by chemoradiation. The primary endpoint is the bladder-intact event-free survival (BI-EFS). Events include: local or distant recurrence, salvage cystectomy, death and switch to platinum-based chemotherapy. We will also evaluate the potential of multiparametric magnetic resonance imaging of the bladder to identify non-responders, and we will assess the clearance of circulating tumor DNA as a biomarker for ICB treatment response. Discussion: This is the first trial in which the efficacy of induction combination ICB followed by chemoradiation is being evaluated to provide bladder-preservation in patients with (locally advanced) urothelial bladder cancer. Clinical Trial Registration: The INDIBLADE trial was registered on clinicaltrials.gov on January 21, 2022 (NCT05200988)

    Prevalence of neoplasia at colonoscopy among testicular cancer survivors treated with platinum-based chemotherapy

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    Testicular cancer survivors (TCS) treated with platinum-based chemotherapy have an increased risk of colorectal cancer (CRC). We determined the yield of colonoscopy in TCS to assess its potential in reducing CRC incidence and mortality. We conducted a colonoscopy screening study among TCS in four Dutch hospitals to assess the yield of colorectal neoplasia. Neoplasia was defined as adenomas, serrated polyps (SPs), advanced adenomas (AAs: ≥10 mm diameter, high-grade dysplasia or ≥25% villous component), advanced serrated polyps (ASPs: ≥10 mm diameter or dysplasia) or CRC. Advanced neoplasia (AN) was defined as AA, ASP or CRC. Colonoscopy yield was compared to average-risk American males who underwent screening colonoscopy (n = 24,193) using a propensity score matched analysis, adjusted for age, smoking status, alcohol consumption and body mass index. A total of 137 TCS underwent colonoscopy. Median age was 50 years among TCS (IQR 43–57) vs 55 years (IQR 51–62) among American controls. A total of 126 TCS were matched to 602 controls. The prevalence of AN was higher in TCS than in controls (8.7% vs 1.7%; P =.0002). Nonadvanced adenomas and SPs were detected in 45.2% of TCS vs 5.5% of controls (P &lt;.0001). No lesions were detected in 46.0% of TCS vs 92.9% of controls (P &lt;.0001). TCS treated with platinum-based chemotherapy have a higher prevalence of neoplasia and AN than matched controls. These results support our hypothesis that platinum-based chemotherapy increases the risk of colorectal neoplasia in TCS. Cost-effectiveness studies are warranted to ascertain the threshold of AN prevalence that justifies the recommendation of colonoscopy for TCS.</p

    Prevalence of neoplasia at colonoscopy among testicular cancer survivors treated with platinum-based chemotherapy

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    Testicular cancer survivors (TCS) treated with platinum-based chemotherapy have an increased risk of colorectal cancer (CRC). We determined the yield of colonoscopy in TCS to assess its potential in reducing CRC incidence and mortality. We conducted a colonoscopy screening study among TCS in four Dutch hospitals to assess the yield of colorectal neoplasia. Neoplasia was defined as adenomas, serrated polyps (SPs), advanced adenomas (AAs: ≥10 mm diameter, high-grade dysplasia or ≥25% villous component), advanced serrated polyps (ASPs: ≥10 mm diameter or dysplasia) or CRC. Advanced neoplasia (AN) was defined as AA, ASP or CRC. Colonoscopy yield was compared to average-risk American males who underwent screening colonoscopy (n = 24,193) using a propensity score matched analysis, adjusted for age, smoking status, alcohol consumption and body mass index. A total of 137 TCS underwent colonoscopy. Median age was 50 years among TCS (IQR 43–57) vs 55 years (IQR 51–62) among American controls. A total of 126 TCS were matched to 602 controls. The prevalence of AN was higher in TCS than in controls (8.7% vs 1.7%; P =.0002). Nonadvanced adenomas and SPs were detected in 45.2% of TCS vs 5.5% of controls (P &lt;.0001). No lesions were detected in 46.0% of TCS vs 92.9% of controls (P &lt;.0001). TCS treated with platinum-based chemotherapy have a higher prevalence of neoplasia and AN than matched controls. These results support our hypothesis that platinum-based chemotherapy increases the risk of colorectal neoplasia in TCS. Cost-effectiveness studies are warranted to ascertain the threshold of AN prevalence that justifies the recommendation of colonoscopy for TCS.</p
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