Development and Phenotype of Heart Failure in Long-Term Survivors of Childhood Cancer: The CVSS Study.

Background The CVSS (Cardiac and Vascular Late Sequelae in Long-Term Survivors of Childhood Cancer) study aimed to investigate the prevalence of different stages of heart failure (HF) in childhood cancer survivors (CCSs) compared with the general population. Methods and Results A total of 1002 CCSs (age range, 23-48 years) diagnosed with neoplasia before an age of 15 years underwent a comprehensive cardiovascular screening. An age- and sex-matched sample from the population-based GHS (Gutenberg Health Study) served as a comparison group. Although prevalence of HF was significantly higher in CCSs, prevalence of different HF stages varied strongly by specific tumor history. Compared with the population, the prevalence ratio was 2.6 (95% CI, 2.4-2.8) for HF stage A and 4.6 (95% CI, 4.1-5.1) for the composite of HF stage B to D in an age- and sex-adjusted Poisson regression model. Multivariable linear regression, adjusting for tumor entities, age, sex, and cardiovascular risk factors, revealed a lower left ventricular ejection fraction in patients with history of bone tumors (ß, -4.30 [95% CI, -5.70 to -2.80]), soft tissue sarcoma (ß, -1.60 [95% CI, -2.90 to -0.30]), and renal tumors (ß, -1.60 [95% CI, -2.80 to -0.29]) compared with the population. The same model for the diastolic marker, ratio of the peak early diastolic filling velocity/lateral mitral annular early diastolic velocity, showed an association only with cardiovascular risk factors but not with tumor entities. Conclusions The prevalence of HF stage A to D was significantly higher among long-term CCSs compared with the population and varied strongly by tumor entity. Systolic dysfunction was primarily associated with tumor entities, whereas diastolic dysfunction was associated with a higher burden of cardiovascular risk factors in CCSs.

Physical Activity as a Treatment for Cancer-Related Fatigue in Children, Adolescents and Young Adults: A Systematic Review.

BACKGROUND: Cancer-related fatigue (CRF) is one of the most common and distressing symptoms in paediatric oncology. Based on previous studies, physical activity interventions are considered to be effective in reducing CRF in adult cancer patients. AIM: The aim of this systematic review is to investigate whether physical activity interventions can reduce CRF in paediatric patients undergoing cancer treatment. METHODOLOGY: A systematic literature search was conducted in PubMed and Sport-Discus in October 2021 to identify intervention studies examining the effects of physical activity on CRF in cancer patients ≤ 21 years of age. Their methodological quality was assessed using the JBI Critical Appraisal Tool. RESULTS: A total of 20 studies (seven randomized-controlled, six quasi-experimental and seven single-arm intervention trials) were included in the review. Nine studies reported significant positive effects of physical activity interventions on CRF in group comparison or within groups. Eleven trials reported no significant changes in CRF. CONCLUSION: Physical activity as a therapeutic intervention in paediatric oncology may have the potential to reduce CRF in childhood cancer patients undergoing cancer treatment. Further high-quality studies with large samples are needed to verify these results and to assess the interdependence of dose and response of physical activity interventions.

Mortality risk among 5-year survivors of childhood cancer in Germany-Results from the CVSS study (Cardiac and Vascular late Sequelae in long-term Survivors of childhood cancer study).

The growing population of long-term childhood cancer survivors is at increased risk for severe, therapy-related late effects and premature mortality. The cardiac and vascular late sequelae in long-term survivors of childhood cancer (CVSS) study is a cohort of patients from Germany diagnosed with a neoplasia prior to 15 years of age in the time period 1980 to 1990. Late mortality was evaluated in a total of 4505 individuals who survived 5 years or more after the initial diagnosis (5-year survivors). Survivors with a second primary tumor were excluded. Standardized mortality ratios (SMRs) were calculated. By December 2014, 400 patients had died. Available cause of death information from 188 individuals was used to estimate cause-specific mortality for all deceased persons. Compared to the population of (former) West Germany, we observed an excess overall mortality risk (SMR = 9.53, 95% confidence interval [CI] = 8.62-10.51). After correcting for missing cause of death information, an increased cancer mortality (SMR = 43.50, 95% CI = 25.79-73.50) in the 5-year survivors was detected. Cardiac death was ascertained in 14 individuals, resulting in an SMR of 10.85 (95% CI = 2.80-32.02) after correcting for missing values. In conclusion, childhood cancer survivors diagnosed in Germany in 1980 to 1990 have a higher mortality risk overall and an elevated risk of dying from cancer and cardiac causes in particular. The results are consistent with those of international cohort studies. However, the reported results are based on few cases and individuals with secondary cancers were excluded.

Identification of an Immunogenic Medulloblastoma-Specific Fusion Involving EPC2 and GULP1.

Medulloblastoma is the most common malignant brain tumor in children. Immunotherapy is yet to demonstrate dramatic results in medulloblastoma, one reason being the low rate of mutations creating new antigens in this entity. In tumors with low mutational burden, gene fusions may represent a source of tumor-specific neoantigens. Here, we reviewed the landscape of fusions in medulloblastoma and analyzed their predicted immunogenicity. Furthermore, we described a new in-frame fusion protein identified by RNA-Seq. The fusion involved two genes on chromosome 2 coding for the enhancer of polycomb homolog 2 (EPC2) and GULP PTB domain containing engulfment adaptor 1 (GULP1) respectively. By qRT-PCR analysis, the fusion was detected in 3 out of 11 medulloblastoma samples, whereby 2 samples were from the same patients obtained at 2 different time points (initial diagnosis and relapse), but not in other pediatric brain tumor entities. Cloning of the full-length sequence indicated that the fusion protein contains the N-terminal enhancer of polycomb-like domain A (EPcA) of EPC2 and the coiled-coil domain of GULP1. In silico analyses predicted binding of the neoantigen-derived peptide to HLA-A*0201. A total of 50% of the fusions described in the literature were also predicted to produce an immunogenic peptide. The EPC2-GULP1 fusion peptide was able to induce a de novo T cell response characterized by interferon gamma release of CD8+ cytotoxic T cells in vitro. While the functional relevance of this fusion in medulloblastoma biology remains to be clarified, our data support an immunotherapeutic approach for pediatric medulloblastoma patients carrying the EPC2-GULP1 fusion and other immunogenic fusions.

Mental health and health-related quality of life in preschool-aged childhood cancer survivors. Results of the prospective cohort study ikidS-OEVA.

OBJECTIVES: Long-term survivors of childhood cancer are at increased risk for sequelae such as poor mental health (MH) or impaired health-related quality of life (HrQoL). We aimed to evaluate early adverse effects on MH and HrQoL in young childhood cancer survivors (YCCS) before school entry. METHODS: In a nationwide prospective cohort study, children with cancer other than brain tumors diagnosed at preschool age and completed cancer treatments were identified from the German Childhood Cancer Registry. The comparison group was children of the same age without a cancer diagnosis who participated in the prospective population-based health survey ikidS. MH problems and HrQoL were assessed by parental versions of the Strengths and Difficulties Questionnaire (SDQ) and the questionnaire for health-related quality of life in children (KINDL), respectively. Associations between cancer and MH as well as HrQoL were analyzed by multivariable linear regression. RESULTS: Of 382 YCCS contacted, 145 were enrolled (mean age 6.6 years) and 124 analyzed. Compared to children without a cancer diagnosis (3683 contacted, 2003 enrolled, 1422 analyzed), YCCS had more MH problems (13% vs. 3%) and slightly worse HrQoL (median 78.7 vs. 80.2 points). In the adjusted analysis, YCCS had higher SDQ scores (2.2 points, 95% confidence interval [CI] 1.3, 3.0) and lower KINDL scores (-2.4 points, 95% CI -3.7, -1.1) compared to children without cancer diagnosis. CONCLUSION: Already at preschool age, YCCS may be at increased risk of MH problems and impaired HrQoL. This could have impacts on subsequent school performance and educational attainment. Follow-up health care for YCCS may include early screening for MH problems and reasons for HrQoL deficits.

Promotion of Arterial Stiffness by Childhood Cancer and Its Characteristics in Adult Long-Term Survivors.

Background Vascular alterations induced by antineoplastic treatment might be considered as a possible underlying mechanism of increased cardiovascular sequelae in childhood cancer survivors (CCSs). We aimed to evaluate arterial stiffness among long-term CCSs and to compare the data against a population-based sample. Methods and Results Arterial stiffness was assessed by digital photoplethysmography (stiffness index; m/s) among 1002 participants of the CVSS (Cardiac and Vascular Late Sequelae in Long-Term Survivors of Childhood Cancer) study, diagnosed with neoplasia (1980-1990) before an age of 15 years. A population-based sample from the GHS (Gutenberg Health Study) (n=5252) was investigated for comparison. All subjects underwent a comprehensive, standardized clinical examination in the same study center. CCSs had higher stiffness index (ß=0.66 m/s; 95% CI, 0.51-0.80 m/s) in multivariable linear regression analysis after adjustment for cardiovascular risk factors compared with the population sample of comparable age range. Stiffer vessels were found among CCSs also in absence of arterial hypertension (ß=0.66; 95% CI, 0.50-0.81) or history of chemotherapy/radiotherapy (ß=0.56; 95% CI, 0.16-0.96) in fully adjusted models. Moreover, stiffness index differed by tumor entity, with highest values in bone and renal tumors. Almost 5.2-fold higher prevalence of stiffness index values exceeding age-specific, population-based reference limits was observed among CCSs compared with GHS participants. Conclusions This is the first study demonstrating increased arterial stiffness among long-term CCSs. The data suggest that vascular compliance might differ in survivors of childhood cancer from the established development concept for arterial stiffness in the population; cancer growth and antineoplastic treatment might be relevant determinants of the pathobiological features. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02181049.

Benefits of Exercise Training for Children and Adolescents Undergoing Cancer Treatment: Results From the Randomized Controlled MUCKI Trial.

Objective: In cancer patients, the impairment in muscle function is a frequently observed phenomenon. However, comprehensive evaluation of the effect of exercise training on muscle function in childhood cancer patients (CCPs) is sparse and therefore investigated in the MUCKI trial. Study Design: In the randomized controlled MUCKI trial, CCPs during intensive cancer treatment and aged 4-18 years were recruited. Eligible patients were enrolled soon after diagnosis as long as they were physically and mentally able to participate in exercise testing and training. Patients of the exercise group (n = 16) participated in average 2.7 ± 1.2 times per week in a combined resistance and endurance training with moderate exercise intensity, for a time period of 8.0 ± 2.1 weeks, while patients of the control group (n = 17) received usual care. Leg strength was evaluated as the primary endpoint. Secondary endpoints were 6-min walk performance, arm strength, body composition, fatigue, and health-related quality of life. Results: Comparisons of pre- and post-intervention results were evaluated by baseline and stratification criteria adjusted analysis and showed positive effects for the exercise group regarding leg strength [F (1, 20) = 5.733; p = 0.027*; η p 2 = 0.223], walking performance [F (1, 25) = 4.270; p = 0.049*; η p 2 = 0.146], fatigue [F (1, 13) = 8.353; p = 0.013*; η p 2 = 0.391], self-esteem [F (1, 6) = 6.823; p = 0.040*; η p 2 = 0.532], and self-reported strength and endurance capacity [F (1, 6) = 6.273; p = 0.046*; η p 2 = 0.511]. No significant differences were found for the other parameters. Conclusion: Within one of the first randomized controlled trials, the present study provides evidence for a positive effect of combined training in CCPs during intensive cancer treatment. Further research is needed to confirm these results and to evaluate their clinical impact. Clinical Trial Registration Number: NCT02612025.

Ceritinib-Induced Regression of an Insulin-Like Growth Factor-Driven Neuroepithelial Brain Tumor.

The insulin-like growth factor (IGF) pathway plays an important role in several brain tumor entities. However, the lack of inhibitors crossing the blood-brain barrier remains a significant obstacle for clinical translation. Here, we targeted the IGF pathway using ceritinib, an off-target inhibitor of the IGF1 receptor (IGF1R) and insulin receptor (INSR), in a pediatric patient with an unclassified brain tumor and a notch receptor 1 (NOTCH1) germline mutation. Pathway analysis of the tumor revealed activation of the sonic hedgehog (SHH), the wingless and integrated-1 (WNT), the IGF, and the Notch pathway. The proliferation of the patient tumor cells (225ZL) was inhibited by arsenic trioxide (ATO), which is an inhibitor of the SHH pathway, by linsitinib, which is an inhibitor of IGF1R and INSR, and by ceritinib. 225ZL expressed INSR but not IGF1R at the protein level, and ceritinib blocked the phosphorylation of INSR. Our first personalized treatment included ATO, but because of side effects, we switched to ceritinib. After 46 days, we achieved a concentration of 1.70 µM of ceritinib in the plasma, and after 58 days, MRI confirmed that there was a response to the treatment. Ceritinib accumulated in the tumor at a concentration of 2.72 µM. Our data suggest ceritinib as a promising drug for the treatment of IGF-driven brain tumors.

Radiation-induced vascular changes in the intracranial irradiation field in medulloblastoma survivors: An MRI study.

BACKGROUND AND PURPOSE: While survival times after treatment of medulloblastoma are increasing, little is known about radiochemotherapy (RCT)-induced cerebrovascular changes. High resolution vessel wall imaging (VWI) sequences are an emerging tool for the evaluation of cerebrovascular diseases. We performed VWI in medulloblastoma long-term survivors to screen for late sequelae of RCT. MATERIAL AND METHODS: Twenty-two pediatric medulloblastoma survivors (mean age 25.8 years (10-53 years); 16.3 years (mean) post primary RCT (range 1-45 years)) underwent 2D VWI-MRI. Vessel wall thickening, contrast enhancement and luminal narrowing were analyzed. The findings were correlated with the patients' radiation protocols. RESULTS: Vessel wall changes were observed the intracranial internal carotid artery (ICA) and the vertebrobasilar circulation (VBC) in 14 of 22 patients (63.6%). In multivariate analysis, time after RCT (OR = 1.38, p < 0.05) was strongest independent predictor for development of vessel wall alterations. The dose of radiation was not a relevant predictor. CONCLUSIONS: With longer follow-up time intracranial vessel wall changes are observed more frequently in medulloblastoma survivors. Thus VWI is a useful tool to monitor vessel wall alterations of cranially irradiated patients, creating the prerequisite for further treatment of late sequelae.

Cardiovascular risk factors are important determinants of platelet-dependent thrombin generation in adult survivors of childhood cancer.

Cardiovascular disease is the most frequent non-malignant cause of morbidity and mortality in adult survivors of childhood or adolescent cancer. Thrombin generation (TG) analysis gives insight in hypercoagulability as an important mechanism linked to cardiovascular risk factors (CVRFs). In 200 individuals, from the cardiac and vascular late sequelae in long-term survivors of childhood cancer study, TG in platelet-rich plasma (PRP) and platelet-free plasma (PFP) at 1pM tissue factor was investigated. Endogenous thrombin potential (ETP) and peak height were the analysed parameters of a TG curve. Sex-specific multivariable linear regression analysis adjusted for age and CVRFs was used to assess the clinical determinants of TG. Females presented with higher ETP and peak height compared to males, both in PRP and PFP. Hypertension (beta estimate, ß: 184.8 [90.7; 278.8]), obesity (ß: 161.9 [63.9; 259.5]), and HbA1c (ß: 715.6 [97.4; 1333.8]) were associated with higher ETP in PRP only. ETP in PRP was positively associated with obesity and HbA1c in both males and females and with dyslipidemia (ß: 253.07 [72.92; 433.22]) and systolic hypertension (ß: 436.7 [119.02; 754.39]) in females only. CVRFs showed no association with TG variables in PFP. In conclusion, this study presents an important relation between traditional CVRFs and TG in the presence of platelets only. Sex-specific differences in TG with females presenting with higher TG, particularly those with dyslipidemia and systolic hypertension, were demonstrated. These results highlight the potential of the platelet-coagulant function in identifying cancer survivors at higher risk for adverse cardiovascular events.

Susceptibility-weighted magnetic resonance imaging of cerebrovascular sequelae after radiotherapy for pediatric brain tumors.

BACKGROUND AND PURPOSE: Due to sensitive neuroimaging techniques, cerebrovascular complications such as cerebral microbleeds (CMB) and cerebral cavernous malformations (CCM) are increasingly recognized as considerable late effects after treatment for pediatric brain tumor. The aim of this study was to analyze CMB in a cohort of patients after cranial irradiation therapy for medulloblastoma or other pediatric brain tumors using susceptibility-weighted magnetic resonance imaging (SWI). MATERIALS AND METHODS: Forty former pediatric brain tumor patients were enrolled in this prospective cross-sectional study and examined by cranial MRI including SWI sequences. Cerebral microbleeds, clinical symptoms and disability were evaluated. RESULTS: Thirty-six (90%) of the examined individuals (mean follow-up age 22.2 y; mean follow-up time 13.5 y) were affected by CMB. Longer follow-up time and higher craniospinal irradiation doses correlated with higher total lesion count (p < 0.01). Thirteen patients (32.5%) presented with clinical symptoms. Individuals with CMB were more severely disabled than patients without CMB (p < 0.05). CONCLUSIONS: Cerebrovascular sequelae occur frequently after treatment for pediatric brain tumor. In this study, a remarkable part of pediatric brain tumor patients presents with CMB. As a sign of vascular damage, they can cause clinical symptoms and may correspond to neurocognitive decline. Further studies are needed to standardize MRI protocols and to improve quality of long-term follow-up.

CD19 Isoforms Enabling Resistance to CART-19 Immunotherapy Are Expressed in B-ALL Patients at Initial Diagnosis.

B-cell acute lymphoblastic leukemia (B-ALL) is the commonest childhood cancer and the prognosis of children with relapsed or therapy refractory disease remains a challenge. Treatment with chimeric antigen receptor-modified T cells targeting the CD19 antigen (CART-19 therapy) has been presented as a promising approach toward improving the outcome of relapsed or refractory disease. However, 10%-20% of the patients suffer another relapse. Epitope-loss under therapy pressure has been suggested as a mechanism of tumor cells to escape the recognition from CART-19 therapy. In this work, we analyzed the expression of CD19 isoforms in a cohort of 14 children with CD19 B-ALL and 6 nonleukemia donors. We showed that an alternatively spliced CD19 mRNA isoform lacking exon 2, and therefore the CART-19 epitope, but not isoforms lacking the transmembrane and cytosolic domains are expressed in leukemic blasts at diagnosis in children and in the bone marrow of nonleukemia donors. Furthermore, we clarified the sequence of a further isoform lacking the epitope recognized by CART-19 therapy and disclosed the presence of new isoforms. In comparison with the children, we showed that alternatively spliced CD19 mRNA isoforms affecting exon 2 are also expressed in 6 adult patients with CD19 B-ALL. On top of that, one of the adults expressed an isoform lacking the CD19 transmembrane and cytosolic domains. In conclusion, we proved that some of the CD19 isoforms contributing to CART-19 escape already preexist at diagnosis and could evolve as a dominant clone during CART-19 therapy suggesting the application of combined treatment approaches.

Prospective analysis of long-term renal function in survivors of childhood Wilms tumor.

BACKGROUND: Considering the improved outcome, a better understanding of the late effects in Wilms tumor survivors (WT-S) is needed. This study was aimed at evaluating renal function and determining the prevalence of clinical and subclinical renal dysfunction in a cohort of WT-S using a multimodal diagnostic approach. METHODS: Thirty-seven WT-S were included in this prospective cross-sectional single center study. To evaluate renal function, glomerular filtration rate (GFR) and urinary protein excretion were assessed. Additionally, kidney sonomorphology and blood pressure were analyzed. RESULTS: All examined WT-S (mean age 28.7 years, mean follow-up 24.8 years) had been treated with a combination of surgery and chemotherapy; 59.5% had received adjuvant radiotherapy. Impaired glomerular renal function was detected in a considerable proportion of WT-S, with age-adjusted cystatin-based GFR estimation below age norm in 55.9%. A lower cystatin-based estimated GFR (eGFR) correlated with longer follow-up time and higher irradiation dose. In 5 patients (13.5%) albuminuria was identified. Analysis of sonomorphology detected compensatory contralateral renal hypertrophy in 83.3% of WT-S. Chronic kidney disease (CKD) ≥ stage II was present in 55.9% of WT-S. Blood pressure measurements revealed arterial hypertension in 15 (40.5%) WT-S (newly diagnosed n=10). In 24.3% both CKD ≥ stage II and arterial hypertension were determined. CONCLUSION: Even though WT-S are believed to carry a low risk for end-stage renal disease, in this study, a remarkable number of WT-S presented with previously unidentified subclinical signs of renal function impairment and secondary morbidity. Therefore, it is important to continue regular follow-up, especially after transition into adulthood.

Personalized therapy: CNS HGNET-BCOR responsiveness to arsenic trioxide combined with radiotherapy.

High-grade neuroepithelial tumor of the central nervous system with BCOR alteration (HGNET-BCOR) is a rare, highly malignant tumor. At the time of this publication, no standard protocol exists to treat this tumor entity. In this work, we tested the responsiveness of the primary culture PhKh1 derived from tumor tissue from a pediatric HGNET-BCOR patient (P1) to inhibitors of the Sonic hedgehog pathway combined with radiation. The SMO inhibitors vismodegib and itraconazole had low effect on the proliferation of the PhKh1 cells. However, the GLI inhibitor arsenic trioxide reduced the expression of GLI target genes in the PhKh1 cells and in combination with radiotherapy significantly decreased their clonogenic potential. PhKh1 cells resistant to arsenic trioxide were characterized by the overexpression of molecular chaperones. We combined arsenic trioxide and radiation in the relapse therapy protocol of P1, achieving complete remission after seven weeks. Clinical remission lasted for six months, when P1 developed systemic metastases. Meanwhile, an increase in the concentration of circulating tumor DNA carrying a BCOR internal tandem duplication was observed. Molecular characterization of a second patient (P2) was also performed. In P2, we detected a larger tandem duplication and greater activation of the Sonic hedgehog pathway than in P1. These findings suggest that combining arsenic trioxide with radiotherapy may represent a new therapeutic approach. Moreover, peripheral blood analysis for circulating tumor DNA could help in the early detection of systemic metastases.

Activation of the basal cell carcinoma pathway in a patient with CNS HGNET-BCOR diagnosis: consequences for personalized targeted therapy.

High grade neuroepithelial tumor of the central nervous system with BCOR alteration (CNS HGNET-BCOR) is a recently described new tumor entity with a dismal prognosis. The objective of this study was to identify and validate pathways deregulated in CNS HGNET-BCOR as basis for targeted therapy approaches.We characterized the BCOR alteration in a pediatric patient with CNS HGNET-BCOR diagnosis by Sanger sequencing and demonstrated an elevated BCOR expression by qRT-PCR and western blot. By whole transcriptome sequencing and Ingenuity Pathway Analysis, we identified the activation of the Sonic Hedgehog (SHH) and of the WNT signaling pathway in two different regions of the primary tumor and of one inoculation metastasis compared to normal brain. We validated the activation of the SHH and of the WNT pathway by qRT-PCR analysis of GLI1 and AXIN2 respectively. GLI1 and AXIN2 were upregulated in the primary tumor and in two inoculation metastases compared to normal brain. Mutational analysis of SMO, PTCH1 and SUFU, three key components of the SHH pathway, revealed a Single Nucleotide Polymorphism (SNP) in PTCH1 (rs357564). We tested the effect of the GLI-inhibitor arsenic trioxide (ATO) on a short-term cell culture isolated from the metastasis. ATO was able to reduce the viability of the cells with an IC50 of 1.3 µM.In summary, these results provide functional evidence of altered BCOR expression and homogeneous coactivation of both the SHH and WNT signaling pathways, building the basis for potential novel therapeutic approaches for patients with a CNS HGNET-BCOR diagnosis.

Next-generation sequencing reveals germline mutations in an infant with synchronous occurrence of nephro- and neuroblastoma.

Although neuro- and nephroblastoma are common solid tumors in children, the simultaneous occurrence is very rare and is often associated with syndromes. Here, we present a unique case of synchronous occurrence of neuro- and nephroblastoma in an infant with no signs of congenital anomalies or a syndrome. We performed genetic testing for possible candidate genes as underlying mutation using the next-generation sequencing (NGS) approach to target 94 genes and 284 single-nucleotide polymorphisms (SNPs) involved in cancer. We uncovered a novel heterozygous germline missense mutation p.F58L (c.172T→C) in the anaplastic lymphoma kinase (ALK) gene and one novel heterozygous rearrangement Q418Hfs(*)11 (c.1254_1264delins TTACTTAGTACAAGAACTG) in the Fanconi anemia gene FANCD2 leading to a truncated protein. Besides, several SNPs associated with the occurrence of neuroblastoma and/or nephroblastoma or multiple primary tumors were identified. The next-generation sequencing approach might in the future be useful not only in understanding tumor etiology but also in recognizing new genetic markers and targets for future personalized therapy.