Genetic determinants of taxane-induced peripheral neuropathy.

The efficacy of taxane­containing regimens has been demonstrated for various cancers, particularly ovarian, endometrial, breast, lung, and prostate cancers. However, extensive taxane-induced toxicities limit their use. Prediction and management of many toxic complications in cancer patients have evolved significantly over the last decade. Peripheral neuropathy is the most typical non-hematological taxane-related complication, and it has a multifactorial pathogenesis. It is often dose-dependent and progressive during therapy and sometimes even after treatment. Unfortunately, the prediction of these common adverse events remains unclear. In the past few years, several polymorphisms of candidate genes with a possible role in the development of this consequence were studied. This minireview aims to highlight the critical yet underappreciated roles of genetic predictors that may increase susceptibility to taxane-induced peripheral neuropathy in cancer patients (Ref. 40). Keywords: taxanes, paclitaxel, docetaxel, peripheral neuropathy, risk factors, genetic polymorphisms.

Chemotherapy-Induced Peripheral Neuropathy (CIPN) as a Predictor of Decreased Quality of Life in Testicular Germ Cell Tumor Survivors.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) after curative treatment for testicular germ cell tumors (GCTs) has been previously reported. It has been shown that CIPN can contribute to impaired quality of life (QOL) in cancer survivors. Herein, we aimed to evaluate CIPN in association with QOL in GCT survivors. PATIENTS AND METHODS: European Organization for Research and Treatment of Cancer (EORTC) Quality of Life - Chemotherapy-Induced Peripheral Neuropathy questionnaire (QLQ-CIPN20) and Quality of Life Questionnaire (QLQ-C30) were prospectively completed by GCT survivors (N = 151) at National Cancer Institute in Slovakia during their annual follow-up. The median follow-up was 10 years (range 4-30). Upon obtaining the scores from each questionnaire, each score from QLQ-C30 was correlated with CIPN defined as high or low (above and below median) as obtained from CIPN20. RESULTS: GCT survivors with high overall CIPN score reported impaired QOL in QLQ-C30. The global health status was lower in survivors with high CIPN versus low CIPN (mean score ± SEM: 67.17 ± 2.00 vs. 86.18 ± 1.76, P < .00001). Survivors with high CIPN reported worse physical, role, emotional, cognitive, and social functioning compared to survivors with low CIPN (all P < .00001). CIPN high survivors perceived more fatigue, nausea, pain, dyspnea, sleeping disorders, and appetite loss compared to CIPN low survivors (all P < .004). Higher burden of CIPN was associated with more financial problems vs CIPN low (mean score ± SEM: 19.70 ± 2.64 vs. 6.67 ± 2.32, P = .00025). Spearman analysis has confirmed negative correlation of overall CIPN20 score with QLQ-C30 global health status (R = -0.53, P < .0001). CONCLUSION: CIPN is a strong predictor of impairment in QOL among GCT survivors. Molecular mechanisms of neurotoxicity should be intensively studied to find preventive and therapeutic strategies.

Exploring the Role of the Gut and Intratumoral Microbiomes in Tumor Progression and Metastasis.

Cancer cell dissemination involves invasion, migration, resistance to stressors in the circulation, extravasation, colonization, and other functions responsible for macroscopic metastases. By enhancing invasiveness, motility, and intravasation, the epithelial-to-mesenchymal transition (EMT) process promotes the generation of circulating tumor cells and their collective migration. Preclinical and clinical studies have documented intensive crosstalk between the gut microbiome, host organism, and immune system. According to the findings, polymorphic microbes might play diverse roles in tumorigenesis, cancer progression, and therapy response. Microbial imbalances and changes in the levels of bacterial metabolites and toxins promote cancer progression via EMT and angiogenesis. In contrast, a favorable microbial composition, together with microbiota-derived metabolites, such as short-chain fatty acids (SCFAs), can attenuate the processes of tumor initiation, disease progression, and the formation of distant metastases. In this review, we highlight the role of the intratumoral and gut microbiomes in cancer cell invasion, migration, and metastatic ability and outline the potential options for microbiota modulation. As shown in murine models, probiotics inhibited tumor development, reduced tumor volume, and suppressed angiogenesis and metastasis. Moreover, modulation of an unfavorable microbiome might improve efficacy and reduce treatment-related toxicities, bringing clinical benefit to patients with metastatic cancer.

Cognitive impairment and biomarkers of gut microbial translocation in testicular germ cell tumor survivors.

Background: Survivors of testicular germ cell tumors (GCT) may suffer from late cognitive impairment. We hypothesized that disruption of intestinal barrier during chemotherapy and/or radiotherapy may be a contributing factor of cognitive dysfunction within the gut-blood-brain axis. Methods: GCT survivors (N = 142) from National Cancer Institute of Slovakia completed the Functional Assessment of Cancer Therapy Cognitive Function questionnaires during their annual follow-up visit at 9-year median (range 4-32). Biomarkers of gut microbial translocation and dysbiosis high mobility group box-1 (HMGB-1), lipopolysaccharide, d-lactate and sCD14 were measured from peripheral blood obtained during the same visit. Each questionnaire score was correlated with biomarkers. Survivors were treated with orchiectomy only (N = 17), cisplatin-based chemotherapy (N = 108), radiotherapy to the retroperitoneum (N = 11) or both (N = 6). Results: GCT survivors with higher sCD14 (above median) had worse cognitive function perceived by others (CogOth domain) (mean ± SEM; 14.6 ± 0.25 vs 15.4 ± 0.25, p = 0.019), lower perceived cognitive abilities (CogPCA domain) (20.0 ± 0.74 vs 23.4 ± 0.73, p = 0.025) and lower overall cognitive function score (109.2 ± 0.74 vs 116.7 ± 1.90, p = 0.021). There were no significant cognitive declines associated with HMGB-1, d-lactate and lipopolysaccharide. Survivors treated with ≥ 400mg/m2 vs < 400mg/m2 of cisplatin-based chemotherapy had a higher lipopolysaccharide (567.8 µg/L ± 42.7 vs 462.9 µg/L ± 51.9, (p = 0.03). Conclusions: sCD14 is a marker of monocytic activation by lipopolysaccharide and may also serve as a promising biomarker of cognitive impairment in long-term cancer survivors. While chemotherapy and radiotherapy-induced intestinal injury may be the underlying mechanism, further research using animal models and larger patient cohorts are needed to explore the pathogenesis of cognitive impairment in GCT survivors within the gut-brain axis.

Microbiome in Cancer Development and Treatment.

Targeting the microbiome, microbiota-derived metabolites, and related pathways represents a significant challenge in oncology. Microbiome analyses have confirmed the negative impact of cancer treatment on gut homeostasis, resulting in acute dysbiosis and severe complications, including massive inflammatory immune response, mucosal barrier disruption, and bacterial translocation across the gut epithelium. Moreover, recent studies revealed the relationship between an imbalance in the gut microbiome and treatment-related toxicity. In this review, we provide current insights into the role of the microbiome in tumor development and the impact of gut and tumor microbiomes on chemo- and immunotherapy efficacy, as well as treatment-induced late effects, including cognitive impairment and cardiotoxicity. As discussed, microbiota modulation via probiotic supplementation and fecal microbiota transplantation represents a new trend in cancer patient care, aiming to increase bacterial diversity, alleviate acute and long-term treatment-induced toxicity, and improve the response to various treatment modalities. However, a more detailed understanding of the complex relationship between the microbiome and host can significantly contribute to integrating a microbiome-based approach into clinical practice. Determination of causal correlations might lead to the identification of clinically relevant diagnostic and prognostic microbial biomarkers. Notably, restoration of intestinal homeostasis could contribute to optimizing treatment efficacy and improving cancer patient outcomes.

Advanced heart failure and cardiac arrhythmia in a young adult survivor of childhood cancer.

The goal of this case report is to describe the young childhood cancer survivor who was treated for nonHodgkin lymphoma with chemotherapy containing anthracycline doxorubicin and who developed symptoms of serious cardiovascular damage 27 years after diagnosis of cancer. The patient is in longterm complete remission of the lymphoma. He started guideline medical therapies for chronic heart failure and had a cardioverter defibrillator implanted for primary prevention of sudden cardiac death. He is currently a candidate for heart transplantation.

Taxane-induced polyneuropathy - current possibilities of prediction and management.

Peripheral neurotoxicity is the most typical non-haematological adverse effect of taxanes. Symptoms are dominated by sensory peripheral neuropathy, the incidence and degree of which depend on the cumulative dose level. The impact of neurotoxicity on the patient´s quality of life is significant, therefore it is necessary to consider the selection of therapy and the patient´s pre-existing risk factors for developing neuropathy and to get acquainted with current management options, including genetic prediction of polyneuropathy. This review article reports on a very common complication of cancer therapy that can be encountered at each internist´s outpatient dispensary.

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.

Long-Term Cognitive Functioning in Testicular Germ-Cell Tumor Survivors.

BACKGROUND: Treatment for cancer may lead to development of cognitive difficulties in cancer survivors. This study aimed to evaluate long-term cognitive functioning (CogF) in germ-cell tumor (GCT) survivors. SUBJECTS, MATERIALS, AND METHODS: GCT survivors (n = 155) from the National Cancer Institute of Slovakia completed the Functional Assessment of Cancer Therapy Cognitive Function at a median of 10 years of follow-up (range: 5-32). The study group consisted of survivors receiving a cisplatin-based chemotherapy, radiotherapy to the retroperitoneal lymph nodes, or both, whereas the control group included survivors treated with orchiectomy only. RESULTS: Of the total survivors, 138 received treatment beyond orchiectomy and 17 controls had orchiectomy alone. Any treatment resulted in significantly greater cognitive difficulties on the overall cognitive function score. Treatment with radiotherapy was associated with cognitive declines in overall cognitive functioning and in subscales for perceived cognitive impairment and cognitive impairment perceived by others (both p < .05). The burden of chemotherapy plus radiotherapy or radiotherapy versus controls resulted in the impairment in all cognitive functioning domains (all p < .05). Overall long-term cognitive impairment was independent of age in the multivariable analysis. CONCLUSION: This prospective study shows that GCT survivors suffer from a long-term CogF impairment. These results may help guide clinicians' decisions in treatment and follow-up of GCTs. IMPLICATIONS FOR PRACTICE: In this study, long-term survivors of germ-cell tumors have reported cognitive impairment after curative treatment with radiotherapy and chemotherapy compared with controls who had treatment with orchiectomy only. These data provide an argument against the use of adjuvant radiotherapy for stage I seminoma. Unnecessary overtreatment with chemotherapy and additional radiotherapy after chemotherapy should be avoided.

The Role of Imaging with Cardiac Computed Tomography in Cardio-Oncology Patients.

Cardiovascular diseases and cancer represent the two most common causes of morbidity and mortality in industrialized countries. With the increase in long-term survival of cancer patients, cardiovascular diseases are the leading cause of mortality for many cancer survivors. In this article, we will review the most common cardiovascular toxicities of cancer therapies and will describe the role of cardiac CT in the detection and monitoring of cardiovascular disease. While there is limited evidence for the use of CT imaging in cancer patients, we will discuss the utility of cardiac CT in the detection and management of coronary artery disease, pericardial and valvular heart disease.

Can we predict clinical cardiotoxicity with cardiac biomarkers in patients after haematopoietic stem cell transplantation?

The long-term prognosis of patients after haematopoietic stem cell transplantation (HSCT) has greatly improved. Cardiac complications represent unresolved and potentially life-threatening conditions in these patients. We prospectively examined 37 consecutive patients with a median age of 28 years who underwent allogeneic HSCT. Biomarkers of cardiac injury were measured serially before the conditioning regimen, the first day after HSCT and then 14, 30, 90 and 180 days after HSCT. Echocardiography was performed before and 1 month after HSCT. Eleven patients (30%) had persistently increased NT-proBNP values, 14 patients (38%) had only transient elevations and 12 (32%) had no changes in NT-proBNP concentrations for a period exceeding 14 days after HSCT. Elevated NT-proBNP values at day 14 after HSCT remained an independent predictor of cardiotoxicity during the first 6 months after HSCT (P < 0.01). Patients with persistent elevations in NT-proBNP also had significant elevations in hs-cTnT concentrations (P < 0.01). Only patients with persistently increased NT-proBNP had a significant worsening in systolic and some diastolic echocardiographic parameters, and we observed in this group the highest values of both cardiomarkers during the 6-month period. Forty-five percent of these patients developed clinical manifestation of cardiotoxicity. Elevations in NT-proBNP concentrations at day 14 after HSCT can predict patients at risk of developing cardiac events during the first 6 months after HSCT. Simultaneous elevations of both cardiomarkers (NT-proBNP and hs-cTnT) persisting 14 days after HSCT had a sensitivity of 83% and a specificity of 80.69%.

Statins in oncological research: from experimental studies to clinical practice.

Statins, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors are commonly used drugs in the treatment of dyslipidemias, primarily raised cholesterol. Recently, many epidemiological and preclinical studies pointed to anti-tumor properties of statins, including anti-proliferative activities, apoptosis, decreased angiogenesis and metastasis. These processes play an important role in carcinogenesis and, therefore, the role of statins in cancer disease is being seriously discussed among oncologists. Anti-neoplastic properties of statins combined with an acceptable toxicity profile in the majority of individuals support their further development as anti-tumor drugs. The mechanism of action, current preclinical studies and clinical efficacy of statins are reviewed in this paper. Moreover, promising results have been reported regarding the statins' efficacy in some cancer types, especially in esophageal and colorectal cancers, and hepatocellular carcinoma. Statins' hepatotoxicity has traditionally represented an obstacle to the prescription of this class of drugs and this issue is also discussed in this review.

Augmenting clinical interpretability of thiopurine methyltransferase laboratory evaluation.

OBJECTIVE: Individuals with decreased thiopurine methyltransferase (TPMT) activity are at risk of adverse effects of thiopurine administration whereas its increased activity may inactivate drugs faster. We evaluated genotype-phenotype correlations in patients with suspected hematological malignancies and inflammatory bowel disease from our region based on findings of nonlinear TPMT enzyme kinetics previously unreported. PATIENTS AND METHODS: The study group comprised 267 individuals. They were screened for the most common variants of low TPMT activity. TPMT activity was measured in erythrocytes using the HPLC rate-blanked method. RESULTS: Thirty-three patients (12.4%) were heterozygous (26 were TPMT*1/*3A, 5 TPMT*1/*2, 2 TPMT *1/*3C) and 1 was a compound heterozygote (*2/*3A). Normal and low normal TPMT activities substantially overlapped in wild-type and heterozygous individuals, whereas high activities were found in 29 wild-type genotyped patients. Extreme and life-threatening toxicity was observed in the compound heterozygote patient. CONCLUSION: Activity measurement performed at diagnosis provides clinicians with information on immediate pharmacokinetic-related adverse events and/or hypermetabolism, and genotyping may indicate the rate of pharmacodynamic thioguanine nucleotide accumulation due to slower overall thiopurine metabolism.

Molecular genetic methods in the diagnosis of myelodysplastic syndromes. A review.

BACKGROUND: Myelodysplastic syndromes (MDS) represent a heterogeneous group of premalignant hematologic disorders characterized by ineffective hematopoiesis, peripheral blood cytopenias and increased risk of progression to acute leukemia. Cytogenetic analysis still plays a central role in the diagnosis of MDS, as clonal chromosomal abnormalities are observed in 30-50% of MDS patients. Despite their technical limitations, standard karyotyping and fluorescence in situ hybridization (FISH) are routinely used for identifying recurrent chromosomal rearrangements. However, using this approach means that submicroscopic and not targeted chromosomal aberrations, as well as somatic mutations and epigenetic changes remain largely undetected. METHODS AND RESULTS: Introduction of methods for the analysis of copy-number variations (CNV), including array-based technologies and Multiplex ligation-dependent probe amplification (MLPA) has provided novel insights into the molecular pathogenesis of MDS and considerably extended possibilities for genetic laboratory testing. Several novel molecular markers have been discovered and used for diagnosis and prognostic evaluation of patients with MDS. At present, mutational analysis is not routinely performed, as the clinical significance of somatic mutations in MDS has only begun to emerge. However, recently introduced Next-generation sequencing (NGS) technologies could help to elucidate the relationship between chromosomal and molecular aberrations in MDS and lead to further improvement in its diagnosis. CONCLUSION: This review focuses on the advantages, limitations, clinical applications and future perspectives of three molecular methods (array-based analysis, MLPA and NGS) currently used in genetic testing and/ or translational research of MDS. In conclusion, a brief summary for clinicians from the routine diagnostic point of view is given.

Thiopurine S-Methyltransferase gene polymorphisms in a healthy Slovak population and pediatric patients with inflammatory bowel disease.

Thiopurine methyltransferase (TPMT) is a key component in thiopurine metabolism. There is an insufficient evidence about the distribution of the genotype frequencies of TPMT variants and frequencies of TPMT alleles associated with intermediate and deficient activity in a healthy Slovak population and pediatric patients with inflammatory bowel disease (IBD). TPMT variant alleles (*1,*2, *3A, *3B, and *3C) were determined in 114 children treated for IBD and in 281 healthy volunteers. Mutant alleles were present in 9/114 (7.89%) in the IBD patients and in 23/281 (8.19%) of probands. The distribution of the most frequent variants of TPMT gene was similar in a healthy population and patients with IBD.

Role of NT-proBNP in detection of myocardial damage in childhood leukemia survivors treated with and without anthracyclines.

BACKGROUND: Exposure to anthracyclines (ANT) during childhood represents a high risk for development of late cardiotoxicity. Cardiotoxicity is usually detected only when clinical symptoms or progressive cardiac dysfunction have already occurred. Early detection of cardiotoxicity may lead to better therapeutic outcome. N-terminal pro-brain natriuretic peptide (NTproBNP) has been hypothesized to reflect increased left ventricular wall stress before development of echocardiographic abnormalities. The aim of this study was to detect cardiac abnormalities using plasma NTproBNP and echocardiography in asymptomatic childhood leukemia survivors treated with or without cardiotoxic anthracycline therapy. METHODS: Serum levels of NTproBNP were determined in 69 asymptomatic survivors of childhood leukemia treated with or without anthracyclines and in 44 apparently healthy controls. The survivors were divided into two treatment groups: 36 patients after chemotherapy containing anthracyclines (ANT) and 33 patients after chemotherapy without anthracyclines (nonANT). Levels of NTproBNP were measured by using the Elecsys 2010 immunoassay analyzer (Roche Diagnostics). Echocardiography using M-mode, two-dimensional and Doppler measurements were performed on the same day as blood samples were obtained for NTproBNP analysis in survivors. RESULTS: Serum levels of NTproBNP were significantly higher in the ANT group than in controls (median 51.52 vs 17.37 pg/ml; p=0.0026). Survivors exposed to ANT had significantly increased levels of NTproBNP compared with patients treated without ANT (median 51.52 vs 12.24 pg/ml; p=0.0002). Female exposed and unexposed survivors had significantly higher NTproBNP levels than males. Four of the 36 survivors (11%) treated with ANT and two of the 33 patients (6%) not exposed to ANT had abnormal NTproBNP levels. Although no patient had echocardiographic abnormalities, significant differences were found in values of left ventricular ejection fraction (LVEF) and deceleration time (DT) between survivors treated with or without anthracyclines. CONCLUSIONS: Higher levels of NTproBNP detected in childhood leukemia survivors after low anthracycline cumulative doses might reflect an initial stage of ANT cardiotoxicity before the development of echocardiographic abnormalities. Although the current studies support NTproBNP as one of the best available biochemical markers of late anthracycline cardiotoxicity, a possible strategy toward further improvement and combination with other cardiac biomarkers and novel echocardiographic methods should be explored in additional studies.

Serial measurements of cardiac biomarkers in patients after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Previous therapy with anthracyclines (ANT) and conditioning regimen followed by hematopoietic stem cell transplantation (HSCT) represents a high risk for development of cardiotoxicity. The aim of this study was to assess subclinical myocardial damage after HSCT using echocardiography and cardiac biomarkers--high sensitive cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and to identify patients at risk of developing clinical cardiotoxicity. PATIENTS AND METHODS: Thirty-seven patients who were treated with allogeneic HSCT for hematologic diseases at median age of 28 years at time of HSCT were studied. Conditioning regimen included either chemotherapy without total body irradiation (TBI) or combination of chemotherapy with TBI. Twenty-nine (78.3%) patients were pretreated with ANT therapy. Cardiac biomarkers were serially measured before conditioning regimen and at days 1, 14 and 30 after HSCT. Cardiac systolic and diastolic functions were assessed before conditioning regimen and 1 month after HSCT by echocardiography. RESULTS: The changes in plasma NT-proBNP and hs-cTnT levels during the 30 days following the HSCT were statistically significant (P < 0.01 v.s. P < 0.01). Persistent elevations of NT-proBNP and hs-cTnT simultaneously for a period exceeding 14 days after HSCT were found in 29.7% patients. Serum concentrations of cardiomarkers were significantly elevated in ANT group compared to non-ANT group. These observations were underscored by the echocardiographic studies which did reveal significant changes in systolic and diastolic parameters. Five of 37 (13.5%) patients developed clinical manifestation of cardiotoxicity. CONCLUSIONS: Elevations in both cardiac biomarkers were found before clinical signs of cardiotoxicity developed. Persistent elevations in NT-pro-BNP and hs-cTnT concentrations simultaneously for a period exceeding 14 days might be used for identification of patients at risk of developing cardiotoxicity and requiring further cardiological follow up.

APEX microarray panel for genotyping polymorphisms in cancer chemotherapy and estimation frequencies in a Slovak population.

AIM: Many studies focus on monitoring response to chemotherapy, adverse effects and prediction of therapeutic effects, which depend on individual gene variability. The amount of various polymorphisms in genes involved in the folate cycle, and other metabolic pathways involved in the metabolism of chemotherapeutic drugs, are an essential topic of such studies. This work focuses on the design and establishment of a pharmacogenetically relevant panel, which could be applied to the rapid genotyping of patients treated with thiopurines, 5-fluorouracil, methotrexate, irinotecan and glucocorticoids. MATERIALS & METHODS: A total of 97 variations in 36 genes associated with side effects of chemotherapeutic treatment were selected. Of these, 94 SNPs were genotyped by the arrayed primer extension (APEX; Asper Biotech Ltd) microarray method or direct sequencing. Variations of tandem repeats or gene deletions were genotyped by capillary electrophoresis and PCR detection. A total of 300 DNA samples from healthy volunteers were tested to estimate genotype frequencies for a Slovak population. All data were checked for Hardy-Weinberg equilibrium and genetic linkage between variations. RESULTS: We designed an APEX microarray for genotyping pharmacologically relevant polymorphisms in patients undergoing chemotherapy. We estimated genotype frequencies for all 97 polymorphisms testing 300 individuals from the Slovak population, which may also serve as an estimate of central European frequencies. These data also allowed for the testing of genetic linkage between loci. Many of the determined genotype frequencies in this study were in similar ranges found in other European populations but four SNPs, rs11760837 (p = 0.018), rs1801265 (p = 0.0375), rs1801394 (p = 0.0066) and rs182455 (p = 0.0083), demonstrated stronger deviation. CONCLUSION: Genetic variability in genes involved in metabolic pathways of chemotherapeutic drugs, such as methotrexate, 5-fluorouracil, thiopurines or irinotecan, is responsible for individual therapy response and development of side effects. A comprehensive approach in genotyping of numerous variants is aimed to improve individual access to patients and the selection of appropriate drugs for treatment. The APEX microarray method is a valuable tool for fast, reliable and cost-effective genotyping of variants which can be used for the typing of known variants in patients prior to treatment as well as in studies searching for new genotype-phenotype associations. The opportunity of adding additional variants during the study makes the APEX microarray technology flexible and suitable for such trials. Original submitted 4 October 2010; Revision submitted 23 November 2010.

Endocrine late effects after hematopoietic stem cell transplantation.

The long-term quality of life of patients after hematopoietic stem cell transplantation (HSCT) represents a multidisciplinary problem. HSCT can induce damage of various organs and tissues-from minimal potentially progressive subclinical changes to life-threatening conditions. Endocrine complications are among the most common late effects observed in survivors after HSCT. The relative risk of these complications is likely to be influenced by the underlying disease, type of therapy, and age at HSCT. Understanding the pathogenetic mechanisms of late complications that can occur after HSCT provides a basis for optimal surveillance and early intervention. Further research is needed for improved risk stratification of patients who are at low and high risk of developing late toxicity. Through collaboration between pathophysiologists, clinicians, and patient associations we can enhance the implementation of prospective studies and set forth effective preventive programs for survivors after HSCT.

Heart transplant in a childhood leukemia survivor: a case report.

OBJECTIVES: Children with acute leukemia often receive therapy that is potentially cardiotoxic. Development of irreversible cardiac impairment requiring heart transplant may appear many years after anticancer therapy. Other possible causes are discussed. MATERIAL AND METHODS: We describe a young leukemia survivor who developed severe heart failure needing a heart transplant. RESULTS: A 4-year-old boy was treated with standard doses of chemotherapy containing cardiotoxic daunorubicin and mitoxantrone, and later, with an allogeneic bone marrow transplant. Twelve years after the diagnosis of acute myeloid leukemia, and following a viral infection of an unknown cause, he developed symptoms of heart failure. Severe dilated cardiomyopathy; and severe, left ventricular dysfunction with ejection fraction of 12% were noted on echocardiography. The patient required a heart transplant 19 years after the diagnosis of leukemia. CONCLUSIONS: Cardiac failure may progressively occur in childhood leukemia survivors. Heart transplant is indicated in patients with refractory hemodynamic decompensation.