Randomized double-blind, placebo-controlled multicenter phase III study of prevention of irinotecan-induced diarrhea by a probiotic mixture containing Bifidobacterium BB-12®Lactobacillus rhamnosus LGG® in colorectal cancer patients.

Background: The incidence of irinotecan-induced diarrhea varies between 60-90%, by which the incidence of severe diarrhea is 20-40%. The objective of this phase III trial was to determine the effectiveness of the probiotic mixture containing Bifidobacterium, BB-12® and Lactobacillus rhamnosus, LGG® in the prophylaxis of irinotecan-induced diarrhea in metastatic colorectal cancer patients due to a reduction in the activity of intestinal beta-D-glucuronidase. Methods: From March 2016 to May 2022, a total of 242 patients with colorectal cancer starting a new line of irinotecan-based therapy were registered to the study in 11 cancer centers in Slovakia. Patients were randomized in a ratio 1:1 to probiotic formula vs. placebo that was administered for 6 weeks. Each capsule of Probio-Tec® BG-Vcap-6.5 contained 2.7x109 colony-forming units (CFU) of 2 lyophilized probiotic strains Bifidobacterium, BB-12® (50%) and Lactobacillus rhamnosus GG, LGG® (50%). Results: Administration of probiotics compared to placebo was not associated with a significant reduction of grade 3/4 diarrhea (placebo arm 11.8% vs. probiotic arm 7.9%, p=0.38). Neither the overall incidence of diarrhea (46.2% vs. 41.2%, p=0.51) nor the incidence of enterocolitis (3.4% vs. 0.9%, p=0.37) was different in the placebo vs. probiotic arm. Subgroup analysis revealed that patients with colostomy had higher incidence of any diarrhea and grade 3/4 diarrhea in the placebo arm compared to the probiotic arm (48.5% vs. 22.2%, p=0.06 and 15.2% vs. 0%, p=0.06, respectively). Moreover, patients on probiotic arm had significantly better diarrhea-free survival (HR = 0.41, 95%CI 0.18 - 0.95, p=0.05) and needed less loperamide (p=0.01) compared to patients on placebo arm. We did not observe any infection caused by probiotic strains used in this study. Conclusion: This study failed to achieve its primary endpoint, and results suggest a lack of benefit of administered probiotic formula for the prevention of irinotecan-induced diarrhea. However, subgroup analysis suggests a possible benefit in patients with colostomy.

Cost-effectiveness of colorectal cancer screening in Slovakia.

BACKGROUND: Colorectal cancer (CRC) is an ideal disease for screening due to known and detectable precursor lesions and slow progression from benign adenoma to invasive cancer. The introduction of organized population-based screening programs reduces the burden of colorectal cancer and increases the quality of the screening process with a more favorable harm to benefit ratio compared to opportunistic screening. METHODS: The study used the microsimulation screening analysis-colon simulation model for the estimation of the effect of various factors on cancer incidence and mortality. The model simulated the Slovakian population from 2018 to 2050. Study includes the analysis of two screening strategies the fecal immunochemical test (FIT) every 2 years and annual FIT. Cost-effectiveness parameters were evaluated comparing each simulated screening scenario with no screening. RESULTS: Compared to no screening, the biennial FIT would detect 29 600 CRC cases and annual FIT 37 800 CRC cases. Mortality due to CRC showed benefits for both strategies with 17,38% reduction in biennial FIT and 24,67% reduction in annual FIT approach. Both screening programs were more costly as well as more effective compared to no screening. The ICER for biennial FIT strategy was 1776 EUR per 1 QALY and for the annual FIT 3991 EUR per 1 QALY. CONCLUSIONS: In summary, this is the first cost-effectiveness analysis focusing on multiple national CRC screening strategies in Slovakia. Both strategies demonstrated cost-effectiveness compared to no screening. However, for optimal population-based programmatic screening strategy, the policymakers should also consider human resources availability, acceptability of screening test among the population or additional resources including the screening funding.

Paclitaxel, Ifosfamide, and Cisplatin in Patients with Poor-prognosis Disseminated Nonseminomatous Germ Cell Tumors with Unfavorable Serum Tumor Marker Decline After First Cycle of Chemotherapy. The GCT-SK-003 Phase II Trial.

BACKGROUND: Germ cell tumors represent highly curable disease even in metastatic stage. However, poor-risk patients with an unfavorable serum tumor marker (STM) decline after the first cycle of chemotherapy represent a subgroup with dismal prognosis, with approximately 50% cure rate using bleomycin, etoposide, and cisplatin (BEP). OBJECTIVE: The aim of this study was to determine the efficacy and safety of paclitaxel, ifosfamide, and cisplatin (TIP) in this patient population. DESIGN SETTING AND PARTICIPANTS: This was an open-labeled, nonrandomized, single-center phase II trial to study the efficacy and toxicity of TIP in the first-line treatment of germ cell tumor patients with an unfavorable decline of STMs. Nineteen patients with a poor prognosis according to the International Germ Cell Cancer Collaboration Group classification and an unfavorable STM decline after the first cycle of chemotherapy were included in this phase II study (NCT02414685). The treatment regimen consisted of paclitaxel 250 mg/m2 on day 1, ifosfamide 1200 mg/m2 on days 1-5, and cisplatin 20 mg/m2 on days 1-5, totally for four cycles. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was complete response (CR) rate. An optimal Simon two-stage design was used with a type I error of 5% and study power of 80%. If fewer than six CRs to study therapy have been observed among the first 19 patients, the study was to be terminated. RESULTS AND LIMITATIONS: A CR was achieved in four (21.1%) patients; therefore, the study was terminated in the first stage. A favorable response rate (CR or partial remission with negative tumor markers) was observed in 14 (78.9%) patients. At a median follow-up period of 35.2 mo (range, 5.6-62.1 mo), ten (52.6%) patients experienced disease progression and eight patients (42.1%) died. The 2-yr progression-free and overall survival was 41.2% (95% confidence interval [CI] 16.8-65.7) and 72.7% (95% CI 48.9-96.4), respectively. TIP was well tolerated, and no unexpected toxicity was observed. No informative biomarkers, including miR-371a-3p was identified. CONCLUSIONS: Treatment modification from the BEP to the TIP regimen in patients with an unfavorable STM decline after the first cycle of chemotherapy was not associated with improved outcome, and four cycles of BEP remain the standard treatment option in this patient population. PATIENT SUMMARY: Poor-risk patients with an unfavorable serum tumor marker decline after the first cycle of chemotherapy represent a subgroup with dismal prognosis, with an approximately 50% cure rate using bleomycin, etoposide, and cisplatin (BEP). Treatment modification from the BEP regimen to the paclitaxel, ifosfamide, and cisplatin regimen in patients with an unfavorable serum tumor marker decline after the first cycle of chemotherapy was not associated with improved outcome, and four cycles of BEP remain the standard treatment option in this patient population.

Challenges and solutions in management of cardiotoxicity induced by checkpoint inhibitors.

BACKGROUND: The use of immune checkpoint inhibitors has dramatically improved the prognosis of many cancer patients. However, their increasing use has also revealed several unexpected side effects - including cardiovascular complications. Increased attention was paid to them in recent years only, especially due to their potentially fatal character. Checkpoint inhibitors cardiotoxicity includes myocarditis, rhythm disorders (atrioventricular blocks, atrial and ventricular arrhythmias), pericarditis, myocardial infarction, left ventricular dysfunction/heart failure, dilated cardiomyopathy, cardiogenic shock and sudden cardiac death. The risk of ICI-associated cardiotoxicity is increased in patients treated with dual immune therapy, in combination with other cardiotoxic drugs, with preexisting cardiac damage, diabetes mellitus, underlying autoimmune disease and some other factors. Currently, there are no guidelines for prediction and management of ICI-associated cardiotoxicity. PURPOSE: Herein, we briefly summarize the findings regarding checkpoint inhibitor-induced cardiotoxicity and provide a new definition of anti-tumor-induced myocarditis together with a suitable design for immune- induced myocarditis management prepared by experts from the field of cardiooncology.

Phase II study of everolimus in refractory testicular germ cell tumors.

BACKGROUND: Testicular germ cell tumors (TGCTs) represent a highly curable disease; however, a small proportion of patients develop disease recurrence. Loss of the tumor-suppressor gene phosphatase and tensin homolog marks the transition from intratubular germ cell neoplasia to invasive GCT and is correlated with disease progression. Inactivation of phosphatase and tensin homolog is associated with deregulation of the PI3K/Akt pathway and increased mammalian target of rapamycin signaling. This study aimed to determine the efficacy and toxicity of a mammalian target of rapamycin inhibitor, everolimus, in patients with refractory TGCTs. METHODS: From December 2011 to February 2015, 15 patients with refractory GCTs were enrolled in the phase II study. All patients were pretreated with at least 2 cisplatin-based therapies; 4 tumors (26.7%) were absolutely refractory to cisplatin and 9 patients (60.0%) had visceral nonpulmonary metastases. Everolimus was administered at a dose of 10mg daily until progression or unacceptable toxicity. The primary end point was the objective response rate, according to Response Evaluation Criteria in Solid Tumors. RESULTS: No objective response was observed, but 6 patients (40.0%) achieved 12-week progression-free survival. During a median follow-up period of 3.6 months (range: 1-35.1mo), all patients experienced disease progression and 11 patients (80.0%) died. Median progression-free survival was 1.7 months (95% CI: 1.1-4.0mo) and median overall survival was 3.6 months (95% CI: 2.0-11.0mo). CONCLUSIONS: This study failed to achieve its primary end point and our data suggest limited efficacy of everolimus against unselected heavily pretreated refractory TGCTs. CONDENSED ABSTRACT: Everolimus showed limited efficacy in unselected heavily pretreated refractory TGCTs. Prolonged disease stabilization could be achieved in selected patients.

Prevention of irinotecan induced diarrhea by probiotics: A randomized double blind, placebo controlled pilot study.

PURPOSE: Diarrhea is one of the dose limiting toxicity of irinotecan. SN-38 is main irinotecan metabolite responsible for diarrhea development, which is excreted in glucuronidated form into the intestine. This study aimed to determine the effectiveness of the probiotics in the prevention of irinotecan induced diarrhea due to reduction of intestinal beta-d-glucuronidase activity. METHODS: Between January 2011 and December 2013, 46 patients with colorectal cancer starting a new line of irinotecan based therapy were included. Patients were randomized 1:1 to probiotics (PRO) or placebo (PLA). Probiotic formula Colon Dophilus™, was administered at a dose of 10×10(9)CFU of bacteria tid, orally for 12 weeks of chemotherapy. The study was prematurely terminated due to slow accrual, when 46 of 220 planned patients were accrued. RESULTS: Twenty-three patients were randomized to PRO and 23 patients to PLA. Administration of probiotics compared to placebo led to a reduction in the incidence of severe diarrhea of grade 3 or 4 (0% for PRO vs. 17.4% for PLA, p=0.11), as well as reduction of the overall incidence of diarrhea (39.1% for PRO vs. 60.9% for PLA, p=0.24) and incidence of enterocolitis (0% for PRO vs. 8.7% for PLA). Patients on PRO used less antidiarrheal drugs compared to PLA. There was no infection caused by probiotic strains recorded. CONCLUSIONS: Administration of probiotics in patients with colorectal cancer treated with irinotecan-based chemotherapy is safe and could lead to a reduction in the incidence and severity of gastrointestinal toxicity.

Personalised chemotherapy based on tumour marker decline in poor prognosis germ-cell tumours (GETUG 13): a phase 3, multicentre, randomised trial.

BACKGROUND: Poor prognosis germ-cell tumours are only cured in about half of patients. We aimed to assess whether treatment intensification based on an early tumour marker decline will improve progression-free survival for patients with germ-cell tumours. METHODS: In this phase 3, multicentre, randomised trial, patients were enrolled from France (20 centres), USA (one centre), and Slovakia (one centre). Patients were eligible if they were older than 16 years, had evidence of testicular, retroperitoneal, or mediastinal non-seminomatous germ cell tumours based on histological findings or clinical evidence and highly elevated serum human chorionic gonadotropin or alfa-fetoprotein concentrations that matched International Germ Cell Cancer Consensus Group poor prognosis criteria. After one cycle of BEP (intravenous cisplatin [20 mg/m(2) per day for 5 days], etoposide [100 mg/m(2) per day for 5 days], and intramuscular or intravenous bleomycin [30 mg per day on days 1, 8, and 15]), patients' human chorionic gonadotropin and alfa-fetoprotein concentrations were measured at day 18-21. Patients with a favourable decline in human chorionic gonadotropin and alfa-fetoprotein continued BEP (Fav-BEP group) for 3 additonal cycles, whereas patients with an unfavourable decline were randomly assigned (1:1) to receive either BEP (Unfav-BEP group) or a dose-dense regimen (Unfav-dose-dense group), consisting of intravenous paclitaxel (175 mg/m(2) over 3 h on day 1) before BEP plus intravenous oxaliplatin (130 mg/m(2) over 3 h on day 10; two cycles), followed by intravenous cisplatin (100 mg/m(2) over 2 h on day 1), intravenous ifosfamide (2 g/m(2) over 3 h on days 10, 12, and 14), plus mesna (500 mg/m(2) at 0, 3, 7 and 11 h), and bleomycin (25 units per day, by continuous infusion for 5 days on days 10-14; two cycles), with granulocyte-colony stimulating factor (lenograstim) support. Centrally blocked computer-generated randomisation stratified by centre was used. The primary endpoint was progression-free survival and the efficacy analysis was done in the intention-to-treat population. The planned trial accrual was completed in May, 2012, and follow-up is ongoing. This study is registered with ClinicalTrials.gov, number NCT00104676. FINDINGS: Between Nov 28, 2003, and May 16, 2012, 263 patients were enrolled and 254 were available for tumour marker assessment. Of these 51 (20%) had a favourable marker assessment, and 203 (80%) had an unfavourable tumour marker decline; 105 were randomly assigned to the Unfav-dose-dense group and 98 to the Unfav-BEP group. 3-year progression-free survival was 59% (95% CI 49-68) in the Unfav-dose-dense group versus 48% (38-59) in the Unfav-BEP group (HR 0·66, 95% CI 0·44-1·00, p=0·05). 3-year progression-free survival was 70% (95% CI 57-81) in the Fav-BEP group (HR 0·66, 95% CI 0·49-0·88, p=0·01 for progression-free survival compared with the Unfav-BEP group). More grade 3-4 neurotoxic events (seven [7%] vs one [1%]) and haematotoxic events occurred in the Unfav-dose-dense group compared with in the Unfav-BEP group; there was no difference in grade 1-2 febrile neutropenia (18 [17%] vs 18 [18%]) or toxic deaths (one [1%] in both groups). Salvage high-dose chemotherapy plus a stem-cell transplant was required in six (6%) patients in the Unfav-dose-dense group and 16 (16%) in the Unfav-BEP group. INTERPRETATION: Personalised treatment with chemotherapy intensification reduces the risk of progression or death in patients with poor prognosis germ-cell tumours and an unfavourable tumour marker decline. FUNDING: Institut National du Cancer (Programme Hospitalier de Recherche Clinique).

Optical mapping of electrical activation in the developing heart.

Specialized conduction tissues mediate coordinated propagation of electrical activity through the adult vertebrate heart. Following activation of the atria, the activation wave is slowed down in the atrioventricular canal or node, after which it spreads rapidly into the left and right ventricles via the His-Purkinje system (HPS). This results in the ventricles being activated from the apex toward the base, which is a hallmark of HPS function. The development of mature HPS function follows significant phases of cardiac morphogenesis. Initially, the cardiac impulse propagates in a slow, linear, and isotropic fashion from the sinus venosus at the most caudal portion of the tubular heart. Although the speed of impulse propagation gradually increases as it travels toward the anterior regions of the heart tube, the actual sequence of ventricular activation in the looped heart proceeds in the same direction as blood flow. Eventually, the immature base-to-apex sequence of ventricular activation undergoes an apparent reversal, changing to the mature apex-to-base pattern. Using an optical mapping approach, we demonstrate that the timing of this last transition shows striking dependence on hemodynamic loading of the ventricle, being accelerated by pressure overload and delayed in left ventricular hypoplasia. Comparison of chick and mammalian hearts revealed some striking similarities as well as key differences in the timing of such events during cardiac organogenesis.

Developmental transitions in electrical activation patterns in chick embryonic heart.

The specialized conduction tissue network mediates coordinated propagation of electrical activity through the adult vertebrate heart. Following activation of the atria, the activation wave is slowed down in the atrioventricular canal or node, then spreads rapidly into the left and right ventricles via the His-Purkinje system (HPS). This results in the ventricle being activated from the apex toward the base and is thought to represent HPS function. The development of mature HPS function in embryogenesis follows significant phases of cardiac morphogenesis. Initially, cardiac impulse propagates in a slow, linear, and isotropic fashion from the sinus venosus at the most caudal portion of the tubular heart. Although the speed of impulse propagation gradually increases, ventricular activation in the looped heart still follows the direction of blood flow. Eventually, the immature base-to-apex sequence of ventricular activation undergoes an apparent reversal, maturing to apex-to-base pattern. The embryonic chick heart has been studied intensively by both electrophysiological and morphological techniques, and the morphology of its conduction system (which is similar to mammals) is well characterized. One interesting but seldom studied feature is the anterior septal branch (ASB), which came sharply to focus (together with the rest of the ventricular conduction system) in our birthdating studies. Using an optical mapping approach, we show that ASB serves to activate ventricular surface between stages 16 and 25, predating the functionality of the His bundle/bundle branches. Heart morphogenesis and conduction system formation are thus linked, and studying the abnormal activation patterns could further our understanding of pathogenesis of congenital heart disease.

Hemodynamic-dependent patterning of endothelin converting enzyme 1 expression and differentiation of impulse-conducting Purkinje fibers in the embryonic heart.

Impulse-conducting Purkinje fibers differentiate from myocytes during embryogenesis. The conversion of contractile myocytes into conduction cells is induced by the stretch/pressure-induced factor, endothelin (ET). Active ET is produced via proteolytic processing from its precursor by ET-converting enzyme 1 (ECE1) and triggers signaling by binding to its receptors. In the embryonic chick heart, ET receptors are expressed by all myocytes, but ECE1 is predominantly expressed in endothelial cells of coronary arteries and endocardium along which Purkinje fiber recruitment from myocytes takes place. Furthermore, co-expression of exogenous ECE1 and ET-precursor in the embryonic heart is sufficient to ectopically convert cardiomyocytes into Purkinje fibers. Thus, localized expression of ECE1 defines the site of Purkinje fiber recruitment in embryonic myocardium. However, it is not known how ECE1 expression is regulated in the embryonic heart. The unique expression pattern of ECE1 in the embryonic heart suggests that blood flow-induced stress/stretch may play a role in patterning ECE1 expression and subsequent induction of Purkinje fiber differentiation. We show that gadolinium, an antagonist for stretch-activated cation channels, downregulates the expression of ECE1 and a conduction cell marker, Cx40, in ventricular chambers, concurrently with delayed maturation of a ventricular conduction pathway. Conversely, pressure-overload in the ventricle by conotruncal banding results in a significant expansion of endocardial ECE1 expression and Cx40-positive putative Purkinje fibers. Coincident with this, an excitation pattern typical of the mature heart is precociously established. These in vivo data suggest that biomechanical forces acting on, and created by, the cardiovascular system during embryogenesis play a crucial role in Purkinje fiber induction and patterning.

The oldest, toughest cells in the heart.

We review here the evolution and development of the earliest components of the cardiac pacemaking and conduction system (PCS) and the turnover or persistence of such cells into old age in the adult vertebrate heart. Heart rate is paced by upstream foci of cardiac muscle near the future sinoatrial junction even before contraction begins. As the tubular heart loops, directional blood flow is maintained through coordinated sphincter function in the forming atrioventricular (AV) canal and outflow segments. Propagation of initially peristaltoid contraction along and between these segments appears to be influenced by physical conditioning and orientation of inner muscle layers as well as by their slow relaxation; all characteristic of definitive conduction tissue. As classical elements of the mature conduction system emerge, such inner 'contour fibres' maintain muscular and electrical continuity between atrial and ventricular compartments. Elements of such primordial architecture are visible also in histological and optical electrical study of fish and frog hearts. In the maturing chick heart, cells within core conducting tissues retain early thymidine labels from the tubular heart stage into adult life, dividing only slowly, if at all. Preliminary evidence from mammals suggest similar function and kinetics for these 'oldest, toughest' cells in the hearts of all vertebrates.

Spatiotemporal pattern of commitment to slowed proliferation in the embryonic mouse heart indicates progressive differentiation of the cardiac conduction system.

Patterns of DNA synthesis in the developing mouse heart between ED7.5-18.5 were studied by a combination of thymidine and bromodeoxyuridine labeling techniques. From earliest stages, we found zones of slow myocyte proliferation at both the venous and arterial poles of the heart, as well as in the atrioventricular region. The labeling index was distinctly higher in nonmyocardial populations (endocardium, epicardium, and cardiac cushions). Ventricular trabeculae showed lower proliferative activity than the ventricular compact layer after their appearance at ED9.5. Low labeling was observed in the pectinate muscles of the atria from ED11.5. The His bundle, bundle branches, and Purkinje fiber network likewise were distinguished by their lack of labeling. Thymidine birthdating (label dilution) showed that the cells in these emerging components of the cardiac conduction system terminally differentiated between ED8.5-13.5. These patterns of slowed proliferation correlate well with those in other species, and can serve as a useful marker for the forming conduction system.

Hemodynamics is a key epigenetic factor in development of the cardiac conduction system.

The His-Purkinje system (HPS) is a network of conduction cells responsible for coordinating the contraction of the ventricles. Earlier studies using bipolar electrodes indicated that the functional maturation of the HPS in the chick embryo is marked by a topological shift in the sequence of activation of the ventricle. Namely, at around the completion of septation, an immature base-to-apex sequence of ventricular activation was reported to convert to the apex-to-base pattern characteristic of the mature heart. Previously, we have proposed that hemodynamics and/or mechanical conditioning may be key epigenetic factors in development of the HPS. We thus hypothesized that the timing of the topological shift marking maturation of the conduction system is sensitive to variation in hemodynamic load. Spatiotemporal patterns of ventricular activation (as revealed by high-speed imaging of fluorescent voltage-sensitive dye) were mapped in chick hearts over normal development, and following procedures previously characterized as causing increased (conotruncal banding, CTB) or reduced (left atrial ligation, LAL) hemodynamic loading of the embryonic heart. The results revealed that the timing of the shift to mature activation displays striking plasticity. CTB led to precocious emergence of mature HPS function relative to controls whereas LAL was associated with delayed conversion to apical initiation. The results from our study indicate a critical role for biophysical factors in differentiation of specialized cardiac tissues and provide the basis of a new model for studies of the molecular mechanisms involved in induction and patterning of the HPS in vivo.

Functional and morphological evidence for a ventricular conduction system in zebrafish and Xenopus hearts.

Zebrafish and Xenopus have become popular model organisms for studying vertebrate development of many organ systems, including the heart. However, it is not clear whether the single ventricular hearts of these species possess any equivalent of the specialized ventricular conduction system found in higher vertebrates. Isolated hearts of adult zebrafish (Danio rerio) and African toads (Xenopus laevis) were stained with voltage-sensitive dye and optically mapped in spontaneous and paced rhythms followed by histological examination focusing on myocardial continuity between the atrium and the ventricle. Spread of the excitation wave through the atria was uniform with average activation times of 20 +/- 2 and 50 +/- 2 ms for zebrafish and Xenopus toads, respectively. After a delay of 47 +/- 8 and 414 +/- 16 ms, the ventricle became activated first in the apical region. Ectopic ventricular activation was propagated significantly more slowly (total ventricular activation times: 24 +/- 3 vs. 14 +/- 2 ms in zebrafish and 74 +/- 14 vs. 35 +/- 9 ms in Xenopus). Although we did not observe any histologically defined tracts of specialized conduction cells within the ventricle, there were trabecular bands with prominent polysialic acid-neural cell adhesion molecule staining forming direct myocardial continuity between the atrioventricular canal and the apex of the ventricle; i.e., the site of the epicardial breakthrough. We thus conclude that these hearts are able to achieve the apex-to-base ventricular activation pattern observed in higher vertebrates in the apparent absence of differentiated conduction fascicles, suggesting that the ventricular trabeculae serve as a functional equivalent of the His-Purkinje system.