Feasibility of whole genome and transcriptome profiling in pediatric and young adult cancers

Whole genome sequencing improves tissue-of-origin diagnosis and treatment options for cancer of unknown primary

Genomics can inform both tissue-of-origin (TOO) and precision treatments for patients with cancer of unknown primary (CUP). Here, we use whole genome and transcriptome sequencing (WGTS) for 72 patients and show diagnostic superiority of WGTS over panel testing (386-523 genes) in 71 paired cases. WGTS detects all reportable DNA features found by panel as well as additional mutations of diagnostic or therapeutic relevance in 76% of cases. Curated WGTS features and a CUP prediction algorithm (CUPPA) trained on WGTS data of known cancer types informs TOO in 71% of cases otherwise undiagnosed by clinicopathology review. WGTS informs treatments for 79% of patients, compared to 59% by panel testing. Finally, WGS of cell-free DNA (cfDNA) from patients with a high cfDNA tumour fraction (>7%), enables high-likelihood CUPPA predictions in 41% of cases. WGTS is therefore superior to panel testing, broadens treatment options, and is feasible using routine pathology samples and cfDNA.

ACR-368, a CHK1/2 Kinase Inhibitor, in Patients With Relapsed or Refractory Desmoplastic Small Round Cell Tumor: Phase I/II Trial Results

PURPOSE

We hypothesized that ACR-368 (prexasertib) would be active in desmoplastic small round cell tumor (DSRCT) because of favorable responses in preclinical models.

METHODS

Preclinical work identified ACR-368 activity in DSRCT, and a phase I/II trial of ACR-368 and irinotecan in patients 12 months and older with relapsed/refractory DSRCT was conducted. The primary objectives were determination of recommended phase II dose (RP2D) and best overall response rate (ORR) at the RP2D in DSRCT, with ≥3 of 16 responses considered promising.

RESULTS

Preclinical data confirmed ACR-368 as potentially therapeutic in DSRCT, and 19 patients were enrolled in a subsequent clinical trial. Treatment was well tolerated, and cytopenias were managed using growth factors. Fifteen of 19 patients, including five of six achieving PR, had previously received irinotecan. The estimated ORR at the RP2D was 23% (lower boundary one-sided 90% CI, 9%), exceeding the unpromising rate of 5%. In addition, three patients with DSRCT had a PR at doses other than the RP2D, bringing the ORR for all doses (n = 19) to 32% (90% CI, 15% to 53%). The median overall survival was 19 months (95% CI, 13 to 36).

CONCLUSION

The RP2D of ACR-368 with irinotecan by age group is ACR-368 105 or 150 mg/m2 once on day 1 (>21 years or ≤21 years, respectively) and irinotecan 15 mg/m2 once daily for 5 days in 21-day cycles for both groups. The study met its primary objective to consider ACR-368 and irinotecan promising in DSRCT and, to our knowledge, is the first incorporating a targeted therapy to achieve this magnitude of response.

Undifferentiated Pleomorphic Sarcoma in Children and Young Adults: A Comprehensive Clinicopathologic, Genomic, and Epigenetic Comparison With Adult Counterparts

Undifferentiated pleomorphic sarcoma (UPS) occurs primarily in older adults and remains a diagnosis of exclusion due to its lack of differentiation and specific molecular alterations. Its occurrence in children is rare and controversial, with an unclear relationship to its adult counterpart. In this study, we aimed to investigate a cohort of 6 pediatric undifferentiated pleomorphic sarcoma (P-UPS, mean 10 years old) and 19 young-adult undifferentiated pleomorphic sarcoma (YA-UPS, mean 30 years old) cases by conducting a comprehensive comparative analysis of their clinicopathologic, genomic, and epigenetic features relative to their adult undifferentiated pleomorphic sarcoma counterparts (A-UPS, n = 100). Histologically, P-UPS and YA-UPS exhibited broad morphologic spectrum. The most frequent alterations across all groups were TP53, CDKN2A/B, and ATRX, with no significant differences among subsets. Notably, RB1 alterations were absent in P-UPS, although representing the second most common alteration in YA-UPS (32%) and A-UPS (41%). PTEN alterations were significantly more prevalent in YA-UPS (26%) compared with that in P-UPS (0%) and A-UPS (6%). Deletions in chromosomes 10, 16q, and 13q, along with amplification of 20q, were the most common across all groups. Except for a higher frequency of 17q amplification in P-UPS (33%) and YA-UPS (26%) compared with that in A-UPS (6%), no other arm-level differences were observed. P-UPS showed a lower mean fraction genome altered compared with YA-UPS and A-UPS, whereas all UPS age groups showed a low tumor mutational burden (mean <10 mut/MB). Pathogenic germline variants of high clinical significance (TP53, NF1, MLH1, CHEK2, and BARD1) were observed only in YA-UPS (31%) and A-UPS (12%) cases. By T-distributed stochastic neighborhood embedding and hierarchical clustering of DNA methylation, the majority of P-UPS and a small subset of YA-UPS grouped in a distinct cluster, characterized by a lower genomic index compared to A-UPS. In contrast, most UPS occurring in young adults genomically parallel their older adults' counterparts. P-UPS and YA-UPS cases exhibited a better disease-specific and progression-free survival, compared with A-UPS cases.

Predisposition Footprints in the Somatic Genome of Wilms Tumors

Approximately 10% of children with cancer harbor a mutation in a predisposition gene. In children with the kidney cancer Wilms tumor, the prevalence is as high as 30%. Certain predispositions are associated with defined histological and clinical features, suggesting differences in tumorigenesis. To investigate this, we assembled a cohort of 137 children with Wilms tumor, of whom 71 had a pathogenic germline or mosaic variant. We examined 237 neoplasms (including two secondary leukemias), utilizing whole-genome sequencing, RNA sequencing, and genome-wide methylation, validating our findings in an independent cohort. Tumor development differed in children harboring a predisposition, depending on the variant gene and its developmental timing. Differences pervaded the repertoire of driver events, including high-risk mutations, the clonal architecture of normal kidneys, and the relatedness of neoplasms from the same individual. Our findings indicate that predisposition may preordain Wilms tumorigenesis, suggesting a variant-specific approach to managing children merits consideration. Significance: Tumors that arise in children with a cancer predisposition may develop through the same mutational pathways as sporadic tumors. We examined this question in the childhood kidney cancer, Wilms tumor. We found that certain predispositions dictate the genetic development of tumors, with clinical implications for these children. See related commentary by Brzezinski and Malkin, p. 258.

Whole genome and transcriptome analysis of pancreatic acinar cell carcinoma elucidates mechanisms of homologous recombination deficiency and unravels novel relevant fusion events

Pancreatic acinar cell carcinoma (PACC) is a rare pancreatic tumor with a heterogeneous clinical course and, except for radical surgery, limited treatment options. We present a comprehensive study encompassing whole-genome and RNA sequencing of 7 tumor samples from 3 metastatic PACC patients to further delineate its genomic landscape and potential therapeutic implications. Our findings reveal distinct signatures of homologous recombination deficiency (HRD) in patients harboring pathogenic germline BRCA1/2 and FANCL mutations, demonstrating favorable responses to poly (ADP-ribose) polymerase 1 (PARP) inhibitors with prolonged disease-free intervals. Additionally, we first describe structural variants in PACC, including BRCA1::TRIM47 fusion and another variant impacting FANCC, both events related to HRD, and we also identify alterations in the mitogen-activated protein kinase (MAPK) pathway, including RAF1 duplication as well as novel BRAF::SORBS2 and MAP7D2::SND1 gene fusions, offering potential targets for therapy. Our study underscores the importance of genome and transcriptome-wide profiling of PACC, to help guide personalized treatment strategies to improve patient outcomes.

Novel structural variants that impact cell cycle genes are elucidated in metastatic gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm of the digestive tract. Despite multiple therapeutic advances, patients with advanced disease frequently develop resistance to tyrosine kinase inhibitors (TKIs), and therefore represent a therapeutic challenge. We employed whole genome sequencing (WGS) on three metastatic GISTs refractory to various TKIs and explored a publicly available cohort of 499 GISTs. This study sheds light on the clinical importance of alterations in cell cycle genes such as cyclin-dependent kinase 2 A (CDKN2A), and cyclin-dependent kinase 2B (CDKN2B), their frequent alteration in metastatic GISTs and their potential role in tumor progression of this neoplasm. Likewise, new structural variations were identified in cyclin-dependent kinase 12 (CDK12). Whole genome profiling of metastatic GIST provides new insights to advance precision care of the disease, focusing on new therapeutic possibilities, especially for emerging targets such as CDK12.

Enhancing the detection of clinically relevant biomarkers in advanced uterine and tubo-ovarian carcinomas through genome-wide analysis

BACKGROUND

Advanced-stage tube-ovarian cancers (TOC) and uterine cancers (UC) significantly contribute to cancer mortality. While surgery achieves clinical remission in most cases, recurrence often necessitates systemic therapy. Recent molecular phenotype studies have advanced targeted therapies. We employed whole genome sequencing (WGS) to investigate biomarkers in gynecologic malignancies.

DESIGN

Ninety-one tumor samples (45 TOC, 46 UC) were analyzed for germline mutations, somatic driver mutations, rearrangements, genome-wide signatures, and molecular phenotypes. A WGS-based high-confidence classifier for homologous recombination deficiency (HRD) was applied. Genomic profiles were correlated with clinical outcomes.

RESULTS

The HRD phenotype was identified in serous carcinoma components, with 50 % of HRD cases showing BRCA1/2 wildtype (33 %) or variants of unknown significance (17 %). HRD correlated with better overall survival in tubo-ovarian serous carcinoma and was linked to responses to platinum therapy and PARP inhibitors. Endometrioid carcinomas showed no HRD phenotype despite BRCA1/2 variants. CDK12-type genomic instability (10 %) occurred in cases with CDK12 rearrangements, and CCNE1 gain (8 %) was observed in CCNE1-amplified cases, independent of copy number. In endometrioid carcinoma, mismatch repair (MMR) deficiency single base substitution signatures, particularly SBS44, contributed to high tumor mutation burden (TMB). Ultra-high TMB was found in two cases with pathogenic POLE and POLQ mutations, exhibiting multiple SBS signatures, including MMR deficiency.

CONCLUSION

Comprehensive genomic profiling of advanced-stage TOC and UC via WGS reveals key biomarkers and therapeutic targets, enhancing diagnostic accuracy and advancing personalized medicine in gynecological cancers.

Emerging molecular phenotypes and potential therapeutic targets in esophageal and gastric adenocarcinoma unearthed by whole genome and transcriptome analyses

BACKGROUND

Adenocarcinoma of the esophagus and stomach demands a deeper molecular understanding to advance treatment strategies and improve patient outcomes. Here, we profiled the genome and transcriptome landscape of these cancers, explored molecular characteristics that are undetectable by other sequencing platforms, and analyzed their potential clinical ramifications.

METHODS

Our study employed state-of-the-art integrative analyses of whole genome and transcriptome sequencing on 51 matched tumor and germline samples from 46 patients. Mutations and rearrangements in clinically relevant cancer genes were investigated and correlated with OncoKB, a knowledge-based precision oncology database, to identify treatment implications. Genome-wide signatures and manually curated molecular profiles were also determined.

RESULTS

The analyses revealed 90 targetable oncogenic mutations and fusions in 63 % of the patients, including novel NTRK, NRG1, ALK, and MET fusions, and structural variants in cancer genes like RAD51B. Also, molecular signatures associated with mismatch repair and homologous recombination deficiency were elucidated. Notably, we identified CDK12-type genomic instability associated with CDK12 fusions.

CONCLUSIONS

Our findings support the potential of whole genome and transcriptome sequencing analyses as a comprehensive approach to identify treatment targets in adenocarcinoma of the stomach and the esophagus, and their application in precision oncology.

Whole genome profiling of primary and metastatic adrenocortical carcinoma unravels significant molecular events

Adrenocortical carcinoma (ACC) is a rare, aggressive malignancy with limited treatment options and poor prognosis, with a 5-year survival rate of about 15 %. This study used whole genome sequencing to characterize the genomic landscape of five patients, one of them with both primary and metastatic samples. Key driver mutations were detected, including APC, JAK1, RFWD3 as well as other genes. Notably, a primary tumor harbored a RAD51 biallelic deleterious translocation, associated with homologous recombination deficiency signature. Large-scale copy neutral loss of heterozygosity (LOH) was identified in four tumors, three had TP53 mutations, with structural variants impacting genes as RB1, CDKN2A, and NF1. A genomic signature specific to mismatch repair was observed in a sample with MHS6 mutation. Two tumors presented novel fusions at TERT locus, including TERT::ZNF521. Comparative analysis between conventional and oncocytic ACC subtypes revealed no significant differences in mutation load, microsatellite instability, or specific gene enrichment. This comprehensive WGS analysis broadens the spectrum of genomic alterations in ACC, highlighting potential molecular targets and differences across subtypes that may inform future therapeutic strategies.

Integrated Whole Genome and Transcriptome Sequencing as a Framework for Pediatric and Adolescent AML Diagnosis and Risk Assessment

Pediatric acute myeloid leukemia (AML) exhibits distinct genetic characteristics, including unique driver alterations and mutations with prognostic and therapeutic significance. Emerging rare, recurrent genetic abnormalities and their associations with outcomes emphasize the need for high-throughput molecular diagnostic tools. Whole genome sequencing (WGS) reliably detects key AML biomarkers such as structural variants, mutations, and copy number alterations. Whole transcriptome sequencing (WTS) complements WGS by uncovering oncogene expression patterns, allele-specific expression, and gene expression signatures. In this study, we describe an integrated WGS and WTS clinical workflow for routine pediatric AML diagnosis and present a systematic evaluation of its application compared to conventional cytogenetics and standard molecular diagnostic methods. Our findings demonstrate that the integrated WGS and WTS (iWGS-WTS) approach improves the identification of clinically relevant genetic alterations, enhancing precise disease classification and risk assessment. Moreover, with advancements in workflow and bioinformatics pipelines, the testing turnaround time can be optimized to meet the demands of clinical decision-making, positioning iWGS-WTS as a practical and superior alternative to traditional diagnostic methods in pediatric AML management.

Rhabdomyosarcoma With EWSR1::NF2 Gene Fusion: A Case Report Potentially Expanding Its Genetic Spectrum

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children, presenting with heterogeneous clinical and molecular subtypes. While gene fusions are predominantly associated with alveolar RMS, spindle cell RMS, especially congenital and intraosseous variants, are also linked to specific gene fusions. Furthermore, recently, FGFR1 kinase-driven RMSs were published. Here, we describe a case of RMS harboring an EWSR1::NF2 gene fusion, a deletion-driven genetic alteration that has not been previously documented in RMS or other soft tissue tumors. The patient was a 29-year-old female who presented with a lobulated ankle mass. Histologic examination revealed a malignant round cell tumor extensively infiltrating large nerve bundles. Immunohistochemical analysis demonstrated rhabdomyoblastic differentiation, consistent with rhabdomyosarcoma. While some areas showed features resembling the sclerosing and others the embryonal subtypes, the overall findings were considered unclassifiable. Targeted RNA sequencing revealed EWSR1(exon 9):: NF2(exon 7) gene fusion, which was confirmed on whole genome and targeted DNA sequencing. The latter did not yield specific diagnostic insights but revealed mutations in TSC2 (p.T1330M), ZFHX3 (p.A301T), and a NOTCH3 rearrangement, all of unknown oncogenic significance. MYC gene amplification was detected, but there was no evidence of chromosome 8 amplification or chromosome 11p15 loss of heterozygosity. Whole genome sequencing revealed a low tumor mutation burden (2.69/Mb) and showed no other significant potentially oncogenic events. DNA methylation studies using dimensionality reduction and unsupervised clustering placed the case within the embryonal RMS subtype. Although the absence of other oncogenic driver alterations suggests that the fusion may have played a pivotal role in pathogenesis, we cannot exclude the possibility that it represents a passenger alteration rather than a true driver mutation. If the former is true, further studies will be required to determine whether this fusion represents a novel RMS subtype or a rare driver in existing subtypes of RMS.

Breadth versus depth: whole transcriptome sequencing has reduced sensitivity for detection of clinically relevant fusions compared to RNA comprehensive genomic profiling

While there is great potential for unbiased next-generation sequencing (NGS) approaches-eg, whole transcriptome sequencing (WTS)-for exploration, discovery, and clinical application in the realm of oncology, there are limitations that should be considered when relying on these methodologies for clinical decision making. When using WTS for the detection of clinically relevant gene fusions in tumor specimens, a key consideration is whether a limited coverage depth (approximately 30-50X) is sufficient for detecting these events, especially in samples with low tumor purity. We demonstrate the reduced sensitivity of both a commercial WTS assay for the detection of clinically relevant fusions in analytical validation control samples and of a research use only (RUO) WTS assay for the detection of clinically relevant fusions in real-world clinical samples compared to RNA comprehensive genomic profiling (CGP). Notably, the RUO WTS assay would not have reported 30% (6/20) of fusions detected using RNA CGP assays in fusion-positive tumor samples, highlighting a potential disadvantage of broader sequencing.

Whole genome profiling of rare pediatric thoracic tumors elucidates a YAP1::LEUTX fusion in an unclassified biphasic embryonal neoplasm

Malignant biphasic tumors of the lungs are rare, more so in the pediatric population. Here, we present the whole-genome characterization of a pleuropulmonary blastoma Type III and an unclassified biphasic thoracic embryonal neoplasm. The pleuropulmonary blastoma harbored pathogenic DICER1 germline and somatic mutations, and additional somatic variants in TP53 and BCOR. The other malignant tumor demonstrated a t(11;19) balanced translocation with a YAP1::LEUTX fusion that was confirmed by fluorescence in situ hybridization. No DICER1 germline or somatic mutation was present. YAP1 and LEUTX have been implicated in tumorigenesis of various neoplasms, and YAP1 fusion genes are an emerging oncogenic entity in a variety of malignancies. In this study we highlight the importance of whole-genome characterization of rare and unclassified tumors to identify biologic mechanisms and potential therapeutic targets.

A review on trends in development and translation of omics signatures in cancer

The field of cancer genomics and transcriptomics has evolved from targeted profiling to swift sequencing of individual tumor genome and transcriptome. The steady growth in genome, epigenome, and transcriptome datasets on a genome-wide scale has significantly increased our capability in capturing signatures that represent both the intrinsic and extrinsic biological features of tumors. These biological differences can help in precise molecular subtyping of cancer, predicting tumor progression, metastatic potential, and resistance to therapeutic agents. In this review, we summarized the current development of genomic, methylomic, transcriptomic, proteomic and metabolic signatures in the field of cancer research and highlighted their potentials in clinical applications to improve diagnosis, prognosis, and treatment decision in cancer patients.

Long-read sequencing of an advanced cancer cohort resolves rearrangements, unravels haplotypes, and reveals methylation landscapes

The Long-Read Personalized OncoGenomics (POG) dataset comprises a cohort of 189 patient tumors and 41 matched normal samples sequenced using the Oxford Nanopore Technologies PromethION platform. This dataset from the POG program and the Marathon of Hope Cancer Centres Network includes DNA and RNA short-read sequence data, analytics, and clinical information. We show the potential of long-read sequencing for resolving complex cancer-related structural variants, viral integrations, and extrachromosomal circular DNA. Long-range phasing facilitates the discovery of allelically differentially methylated regions (aDMRs) and allele-specific expression, including recurrent aDMRs in the cancer genes RET and CDKN2A. Germline promoter methylation in MLH1 can be directly observed in Lynch syndrome. Promoter methylation in BRCA1 and RAD51C is a likely driver behind homologous recombination deficiency where no coding driver mutation was found. This dataset demonstrates applications for long-read sequencing in precision medicine and is available as a resource for developing analytical approaches using this technology.

Identifying barriers and opportunities to facilitate the uptake of whole genome sequencing in paediatric haematology and oncology practice

BACKGROUND

The clinical utility of whole genome sequencing (WGS) in paediatric cancer has been demonstrated in recent years. WGS has been routinely available in the National Health Service (NHS) England for all children with cancer in England since 2021, but its uptake has been variable geographically. To explore the underlying barriers to routine use of WGS in this population across England and more widely in the United Kingdom (UK) and the Republic of Ireland (ROI), a one-day workshop was held in Cambridge, United Kingdom in October 2022.

METHODS

Following a series of talks, delegates participated in open, round-table discussions to outline local and broader challenges limiting routine WGS for diagnostic work-up for children with cancer in their Principal Treatment Centres (PTCs) and Genomic Laboratory Hubs (GLHs). Within smaller groups, delegates answered structured questions regarding clinical capability, education and training needs, and workforce competence and requirements. Data was recorded, centrally collated, and analysed following the event using thematic analysis.

RESULTS

Sixty participants attended the workshop with broad representation from the 20 PTCs across the UK and ROI and the seven GLHs in England. All healthcare professionals involved in the WGS pathway were represented, including paediatric oncologists, clinical geneticists, clinical scientists, and histopathologists. The main themes highlighted by the group in ensuring equitable access to WGS identified were: lack of knowledge equity between NHS trusts, with a perception of WGS being for research only; and perception of lack of financial support for the clinical process surrounding WGS, including lack of time to take informed consent from patients. The latter also included limited trained staff available for data interpretation, affecting the turnaround time for reporting. Finally, the need for an integrated digital pathway to order, track, and return data to clinicians was highlighted.

CONCLUSION

At the workshop, the general motivation for including WGS in the diagnostic work up for children with cancer was high throughout the UK, however a perceived lack of resources and education opportunities limit the widespread use of this commissioned assay. This workshop has led to some recommendations to increase access to WGS in this population in England and more widely in the devolved national of the UK and the ROI.

Whole genome sequencing elucidates etiological differences in MCPyV-negative Merkel cell carcinoma

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine neoplasm of the skin. Immunosuppression, ultraviolet radiation and the integration of Merkel cell polyomavirus (MCPyV) have all been shown to be involved in the pathogenesis of this malignancy. We performed whole genome sequencing on two MCPyV-negative cases of MCC that demonstrated very different clinical presentations and outcomes, and mutational profiles. The first case exhibited a highly aggressive clinical course, absence of UV-signature mutations and a low tumor mutational burden. A rearrangement in the tumor suppressor gene SUFU was identified, a likely driver and potential target of the Hedgehog signaling pathway. Meanwhile, the second case exhibited a less aggressive behavior, harbored UV-signature mutations, and a high mutational burden including mutations in TP53 and RB1.

Precision oncology: current and future platforms for treatment selection

Genomic profiling of hundreds of cancer-associated genes is now a component of routine cancer care. DNA sequencing can identify mutations, mutational signatures, and structural alterations predictive of therapy response and assess for heritable cancer risk, but it has been less useful for identifying predictive biomarkers of sensitivity to cytotoxic chemotherapies, antibody drug conjugates, and immunotherapies. The clinical adoption of molecular profiling platforms such as RNA sequencing better suited to identifying those patients most likely to respond to immunotherapies and drug combinations will be critical to expanding the benefits of precision oncology. This review discusses the potential advantages of innovative molecular and functional profiling platforms designed to replace or complement targeted DNA sequencing and the major hurdles to their clinical adoption.

Benefits for children with suspected cancer from routine whole-genome sequencing

Clinical whole-genome sequencing (WGS) has been shown to deliver potential benefits to children with cancer and to alter treatment in high-risk patient groups. It remains unknown whether offering WGS to every child with suspected cancer can change patient management. We collected WGS variant calls and clinical and diagnostic information from 281 children (282 tumors) across two English units (n = 152 from a hematology center, n = 130 from a solid tumor center) where WGS had become a routine test. Our key finding was that variants uniquely attributable to WGS changed the management in ~7% (20 out of 282) of cases while providing additional disease-relevant findings, beyond standard-of-care molecular tests, in 108 instances for 83 (29%) cases. Furthermore, WGS faithfully reproduced every standard-of-care molecular test (n = 738) and revealed several previously unknown genomic features of childhood tumors. We show that WGS can be delivered as part of routine clinical care to children with suspected cancer and can change clinical management by delivering unexpected genomic insights. Our experience portrays WGS as a clinically impactful assay for routine practice, providing opportunities for assay consolidation and for delivery of molecularly informed patient care.

Epigenetic determinants of fusion-driven sarcomas: paradigms and challenges

We describe exciting recent advances in fusion-driven sarcoma etiology, from an epigenetics perspective. By exploring the current state of the field, we identify and describe the central mechanisms that determine sarcomagenesis. Further, we discuss seminal studies in translational genomics, which enabled epigenetic characterization of fusion-driven sarcomas. Important context for epigenetic mechanisms include, but are not limited to, cell cycle and metabolism, core regulatory circuitry, 3-dimensional chromatin architectural dysregulation, integration with ATP-dependent chromatin remodeling, and translational animal modeling. Paradoxically, while the genetic requirements for oncogenic transformation are highly specific for the fusion partners, the epigenetic mechanisms we as a community have uncovered are categorically very broad. This dichotomy prompts the question of whether the investigation of rare disease epigenomics should prioritize studying individual cell populations, thereby examining whether the mechanisms of chromatin dysregulation are specific to a particular tumor. We review recent advances focusing on rhabdomyosarcoma, synovial sarcoma, alveolar soft part sarcoma, clear cell sarcoma, undifferentiated round cell sarcoma, Ewing sarcoma, myxoid/round liposarcoma, epithelioid hemangioendothelioma and desmoplastic round cell tumor. The growing number of groundbreaking discoveries in the field, motivated us to anticipate further exciting advances in the area of mechanistic epigenomics and direct targeting of fusion transcription factors in the years ahead.

Whole genome and transcriptome integrated analyses guide clinical care of pediatric poor prognosis cancers

The role for routine whole genome and transcriptome analysis (WGTA) for poor prognosis pediatric cancers remains undetermined. Here, we characterize somatic mutations, structural rearrangements, copy number variants, gene expression, immuno-profiles and germline cancer predisposition variants in children and adolescents with relapsed, refractory or poor prognosis malignancies who underwent somatic WGTA and matched germline sequencing. Seventy-nine participants with a median age at enrollment of 8.8 y (range 6 months to 21.2 y) are included. Germline pathogenic/likely pathogenic variants are identified in 12% of participants, of which 60% were not known prior. Therapeutically actionable variants are identified by targeted gene report and whole genome in 32% and 62% of participants, respectively, and increase to 96% after integrating transcriptome analyses. Thirty-two molecularly informed therapies are pursued in 28 participants with 54% achieving a clinical benefit rate; objective response or stable disease ≥6 months. Integrated WGTA identifies therapeutically actionable variants in almost all tumors and are directly translatable to clinical care of children with poor prognosis cancers.

Molecular-guided therapy for the treatment of patients with relapsed and refractory childhood cancers: a Beat Childhood Cancer Research Consortium trial

BACKGROUND

Children with relapsed central nervous system (CNS tumors), neuroblastoma, sarcomas, and other rare solid tumors face poor outcomes. This prospective clinical trial examined the feasibility of combining genomic and transcriptomic profiling of tumor samples with a molecular tumor board (MTB) approach to make real‑time treatment decisions for children with relapsed/refractory solid tumors.

METHODS

Subjects were divided into three strata: stratum 1-relapsed/refractory neuroblastoma; stratum 2-relapsed/refractory CNS tumors; and stratum 3-relapsed/refractory rare solid tumors. Tumor samples were sent for tumor/normal whole-exome (WES) and tumor whole-transcriptome (WTS) sequencing, and the genomic data were used in a multi-institutional MTB to make real‑time treatment decisions. The MTB recommended plan allowed for a combination of up to 4 agents. Feasibility was measured by time to completion of genomic sequencing, MTB review and initiation of treatment. Response was assessed after every two cycles using Response Evaluation Criteria in Solid Tumors (RECIST). Patient clinical benefit was calculated by the sum of the CR, PR, SD, and NED subjects divided by the sum of complete response (CR), partial response (PR), stable disease (SD), no evidence of disease (NED), and progressive disease (PD) subjects. Grade 3 and higher related and unexpected adverse events (AEs) were tabulated for safety evaluation.

RESULTS

A total of 186 eligible patients were enrolled with 144 evaluable for safety and 124 evaluable for response. The average number of days from biopsy to initiation of the MTB-recommended combination therapy was 38 days. Patient benefit was exhibited in 65% of all subjects, 67% of neuroblastoma subjects, 73% of CNS tumor subjects, and 60% of rare tumor subjects. There was little associated toxicity above that expected for the MGT drugs used during this trial, suggestive of the safety of utilizing this method of selecting combination targeted therapy.

CONCLUSIONS

This trial demonstrated the feasibility, safety, and efficacy of a comprehensive sequencing model to guide personalized therapy for patients with any relapsed/refractory solid malignancy. Personalized therapy was well tolerated, and the clinical benefit rate of 65% in these heavily pretreated populations suggests that this treatment strategy could be an effective option for relapsed and refractory pediatric cancers.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02162732. Prospectively registered on June 11, 2014.

NIPBL::NACC1 Fusion Hepatic Carcinoma

Several reports describing a rare primary liver tumor with histologic features reminiscent of follicular thyroid neoplasms have been published under a variety of descriptive terms including thyroid-like, solid tubulocystic, and cholangioblastic cholangiocarcinoma. Although these tumors are considered to represent histologic variants, they lack classic features of cholangiocarcinoma and have unique characteristics, namely immunoreactivity for inhibin and NIPBL::NACC1 fusions. The purpose of this study is to present clinicopathologic and molecular data for a large series of these tumors to better understand their pathogenesis. We identified 11 hepatic tumors with these features. Immunohistochemical and NACC1 and NIPBL fluorescence in situ hybridization assays were performed on all cases. Four cases had available material for whole-genome sequencing (WGS) analysis. Most patients were adult women (mean age: 42 y) who presented with abdominal pain and large hepatic masses (mean size: 14 cm). Ten patients had no known liver disease. Of the patients with follow-up information, 3/9 (33%) pursued aggressive behavior. All tumors were composed of bland cuboidal cells with follicular and solid/trabecular growth patterns in various combinations, were immunoreactive for inhibin, showed albumin mRNA by in situ hybridization, and harbored the NIPBL::NACC1 fusion by fluorescence in situ hybridization. WGS corroborated the presence of the fusion in all 4 tested cases, high tumor mutational burden in 2 cases, and over 30 structural variants per case in 3 sequenced tumors. The cases lacked mutations typical of conventional intrahepatic cholangiocarcinoma. In this report, we describe the largest series of primary inhibin-positive hepatic neoplasms harboring a NIPBL::NACC1 fusion and the first WGS analysis of these tumors. We propose to name this neoplasm NIPBL:NACC1 fusion hepatic carcinoma.

Micro-costing of genetic diagnostics in acute leukemia in Sweden: from standard-of-care to whole-genome sequencing

AIMS AND BACKGROUND

Whole-genome sequencing (WGS) is increasingly applied in clinical practice and expected to replace standard-of-care (SoC) genetic diagnostics in hematological malignancies. This study aims to assess and compare the fully burdened cost ('micro-costing') per patient for Swedish laboratories using WGS and SoC, respectively, in pediatric and adult patients with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML).

METHODS

The resource use and cost details associated with SoC, e.g. chromosome banding analysis, fluorescent in situ hybridization, and targeted sequencing analysis, were collected via activity-based costing methods from four diagnostic laboratories. For WGS, corresponding data was collected from two of the centers. A simulation-based scenario model was developed for analyzing the WGS cost based on different annual sample throughput to evaluate economy of scale.

RESULTS

The average SoC total cost per patient was €2,465 for pediatric AML and €2,201 for pediatric ALL, while in adults, the corresponding cost was €2,458 for AML and €1,207 for ALL. The average WGS cost (90x tumor/30x normal; sequenced on the Illumina NovaSeq 6000 platform) was estimated to €3,472 based on an annual throughput of 2,500 analyses, however, with an annual volume of 7,500 analyses the average cost would decrease by 23% to €2,671.

CONCLUSION

In summary, WGS is currently more costly than SoC, however the cost can be reduced by utilizing laboratories with higher throughput and by the expected decline in cost of reagents. Our data provides guidance to decision-makers for the resource allocation needed when implementing WGS in diagnostics of hematological malignancies.

HRD related signature 3 predicts clinical outcome in advanced tubo-ovarian high-grade serous carcinoma

OBJECTIVES

We evaluated usability of single base substitution signature 3 (Sig3) as a biomarker for homologous recombination deficiency (HRD) in tubo-ovarian high-grade serous carcinoma (HGSC).

MATERIALS AND METHODS

This prospective observational trial includes 165 patients with advanced HGSC. Fresh tissue samples (n = 456) from multiple intra-abdominal areas at diagnosis and after neoadjuvant chemotherapy (NACT) were collected for whole-genome sequencing. Sig3 was assessed by fitting samples independently with COSMIC v3.2 reference signatures. An HR scar assay was applied for comparison. Progression-free survival (PFS) and overall survival (OS) were studied using Kaplan-Meier and Cox regression analysis.

RESULTS

Sig3 has a bimodal distribution, eliminating the need for an arbitrary cutoff typical in HR scar tests. Sig3 could be assessed from samples with low (10%) cancer cell proportion and was consistent between multiple samples and stable during NACT. At diagnosis, 74 (45%) patients were HRD (Sig3+), while 91 (55%) were HR proficient (HRP, Sig3-). Sig3+ patients had longer PFS and OS than Sig3- patients (22 vs. 13 months and 51 vs. 34 months respectively, both p < 0.001). Sig3 successfully distinguished the poor prognostic HRP group among BRCAwt patients (PFS 19 months for Sig3+ and 13 months for Sig3- patients, p < 0.001). However, Sig3 at diagnosis did not predict chemoresponse anymore in the first relapse. The patient-level concordance between Sig3 and HR scar assay was 87%, and patients with HRD according to both tests had the longest median PFS.

CONCLUSIONS

Sig3 is a prognostic marker in advanced HGSC and useful tool in patient stratification for HRD.

The importance of escalating molecular diagnostics in patients with low-grade pediatric brain cancer

Pilocytic astrocytomas are the most common pediatric brain tumors, typically presenting as low-grade neoplasms. We report two cases of pilocytic astrocytoma with atypical tumor progression. Case 1 involves a 12-yr-old boy with an unresectable suprasellar tumor, negative for BRAF rearrangement but harboring a BRAF p.V600E mutation. He experienced tumor size reduction and stable disease following dabrafenib treatment. Case 2 describes a 6-yr-old boy with a thalamic tumor that underwent multiple resections, with no actionable driver detected using targeted next-generation sequencing. Whole-genome and RNA-seq analysis identified an internal tandem duplication in FGFR1 and RAS pathway activation. Future management options include FGFR1 inhibitors. These cases demonstrate the importance of escalating molecular diagnostics for pediatric brain cancer, advocating for early reflexing to integrative whole-genome sequencing and transcriptomic profiling when targeted panels are uninformative. Identifying molecular drivers can significantly impact treatment decisions and improve patient outcomes.

Molecular Techniques and Gene Mutations in Myelodysplastic Syndromes

Sequencing technology, particularly next-generation sequencing, has highlighted the importance of gene mutations in myelodysplastic syndromes (MDSs). Mutations affecting DNA methylation, chromatin modification, RNA splicing, cohesin complex, and other pathways are present in most MDS cases and often have prognostic and clinical implications. Updated international diagnostic guidelines as well as the new International Prognostic Scoring System-Molecular incorporate molecular data into the diagnosis and prognostication of MDS. With whole-genome sequencing predicted to become the future standard of genetic evaluation, it is likely that MDS diagnosis and management will become increasingly personalized based on an individual's clinical and genomic profile.

Subclonal Somatic Copy-Number Alterations Emerge and Dominate in Recurrent Osteosarcoma

Multiple large-scale genomic profiling efforts have been undertaken in osteosarcoma to define the genomic drivers of tumorigenesis, therapeutic response, and disease recurrence. The spatial and temporal intratumor heterogeneity could also play a role in promoting tumor growth and treatment resistance. We conducted longitudinal whole-genome sequencing of 37 tumor samples from 8 patients with relapsed or refractory osteosarcoma. Each patient had at least one sample from a primary site and a metastatic or relapse site. Subclonal copy-number alterations were identified in all patients except one. In 5 patients, subclones from the primary tumor emerged and dominated at subsequent relapses. MYC gain/amplification was enriched in the treatment-resistant clones in 6 of 7 patients with multiple clones. Amplifications in other potential driver genes, such as CCNE1, RAD21, VEGFA, and IGF1R, were also observed in the resistant copy-number clones. A chromosomal duplication timing analysis revealed that complex genomic rearrangements typically occurred prior to diagnosis, supporting a macroevolutionary model of evolution, where a large number of genomic aberrations are acquired over a short period of time followed by clonal selection, as opposed to ongoing evolution. A mutational signature analysis of recurrent tumors revealed that homologous repair deficiency (HRD)-related SBS3 increases at each time point in patients with recurrent disease, suggesting that HRD continues to be an active mutagenic process after diagnosis. Overall, by examining the clonal relationships between temporally and spatially separated samples from patients with relapsed/refractory osteosarcoma, this study sheds light on the intratumor heterogeneity and potential drivers of treatment resistance in this disease.

SIGNIFICANCE

The chemoresistant population in recurrent osteosarcoma is subclonal at diagnosis, emerges at the time of primary resection due to selective pressure from neoadjuvant chemotherapy, and is characterized by unique oncogenic amplifications.

A systematic review of the prevalence of pathogenic or likely pathogenic germline variants in individuals with FOXO1 fusion-positive rhabdomyosarcoma

Several cancer predisposition syndromes (CPS) are reported to predispose to rhabdomyosarcoma, most frequently in children with embryonal rhabdomyosarcoma. There are lingering questions over the role of CPS in individuals with alveolar rhabdomyosarcoma (ARMS), which are frequently driven by FOXO1 fusion oncoproteins. We conducted a systematic review to identify patients with FOXO1 fusion-positive ARMS (FP-ARMS) who underwent germline DNA sequencing. We estimated the prevalence of pathogenic/likely pathogenic (P/LP) variants in cancer predisposing genes (CPGs) and of CPSs. We included 19 publications reporting on 191 patients with FP-ARMS. P/LP variants in CPGs were identified in 26/191 (13.6%) patients, nine (4.9%) of which were associated with a CPS diagnosis. Evidence for causal associations between CPSs and FP-ARMS could not be assessed with available data from this review. Only one patient was affected with a CPS known to predispose to rhabdomyosarcoma, Li-Fraumeni syndrome. Typical CPS associations with rhabdomyosarcoma are rare, but not nonexistent, in patients with FP-ARMS. FOXO1 fusion status, alone, is insufficient for clinicians to rely on to distinguish between patients with/without CPS.

Different methods to estimate the phase of neural rhythms agree, but only during times of low uncertainty

Rhythms are a common feature of brain activity. Across different types of rhythms, the phase has been proposed to have functional consequences, thus requiring its accurate specification from noisy data. Phase is conventionally specified using techniques that presume a frequency band-limited rhythm. However, in practice, observed brain rhythms are typically non-sinusoidal and amplitude modulated. How these features impact methods to estimate phase remains unclear. To address this, we consider three phase estimation methods, each with different underlying assumptions about the rhythm. We apply these methods to rhythms simulated with different generative mechanisms and demonstrate inconsistency in phase estimates across the different methods. We propose two improvements to the practice of phase estimation: (1) estimating confidence in the phase estimate, and (2) examining the consistency of phase estimates between two (or more) methods.

TEQUILA-seq: a versatile and low-cost method for targeted long-read RNA sequencing

Long-read RNA sequencing (RNA-seq) is a powerful technology for transcriptome analysis, but the relatively low throughput of current long-read sequencing platforms limits transcript coverage. One strategy for overcoming this bottleneck is targeted long-read RNA-seq for preselected gene panels. We present TEQUILA-seq, a versatile, easy-to-implement, and low-cost method for targeted long-read RNA-seq utilizing isothermally linear-amplified capture probes. When performed on the Oxford nanopore platform with multiple gene panels of varying sizes, TEQUILA-seq consistently and substantially enriches transcript coverage while preserving transcript quantification. We profile full-length transcript isoforms of 468 actionable cancer genes across 40 representative breast cancer cell lines. We identify transcript isoforms enriched in specific subtypes and discover novel transcript isoforms in extensively studied cancer genes such as TP53. Among cancer genes, tumor suppressor genes (TSGs) are significantly enriched for aberrant transcript isoforms targeted for degradation via mRNA nonsense-mediated decay, revealing a common RNA-associated mechanism for TSG inactivation. TEQUILA-seq reduces the per-reaction cost of targeted capture by 2-3 orders of magnitude, as compared to a standard commercial solution. TEQUILA-seq can be broadly used for targeted sequencing of full-length transcripts in diverse biomedical research settings.

Pediatric Precision Medicine at the National Cancer Center Japan: Prospective Genomic Study of Pediatric Patients with Cancer as Part of the TOP-GEAR Project

PURPOSE

This single-center, prospective molecular profiling study characterizes genomic alterations and identifies therapeutic targets in advanced pediatric solid tumors.

METHODS

As part of the TOP-GEAR (Trial of Onco-Panel for Gene profiling to Estimate both Adverse events and Response by cancer treatment) project at the National Cancer Center (NCC), Japan, we enrolled pediatric patients with a refractory or recurrent disease during August 2016-December 2021 and performed genomic analysis of matched tumors and blood using originally developed cancer gene panels, NCC Oncopanel (ver. 4.0) and NCC Oncopanel Ped (ver. 1.0).

RESULTS

Of 142 patients (age, 1-28 years) enrolled, 128 (90%) were evaluable for genomic analysis; 76 (59%) patients harbored at least one reportable somatic or germline alteration. The tumor samples were collected during the initial diagnosis in 65 (51%) patients, after treatment initiation in 11 (9%) patients, and upon either disease progression or relapse in 52 (41%) patients. The leading altered gene was TP53, followed by MYCN, MYC, CDKN2A, and CDK4. The commonly affected molecular processes were transcription, cell-cycle regulation, epigenetic modifiers, and RAS/mitogen-activated protein kinase signaling. Twelve (9%) patients carried pathogenic germline variants in cancer-predisposing genes. Potentially actionable findings were identified in 40 (31%) patients; to date, 13 (10%) patients have received the recommended therapy on the basis of their genomic profiles. Although four patients had access to targeted therapy through clinical trials, the agents were used in nine patients in an off-label setting.

CONCLUSION

The implementation of genomic medicine has furthered our understanding of tumor biology and provided new therapeutic strategies. However, the paucity of proposed agents limits the full potential of actionability, emphasizing the significance of facilitating access to targeted cancer therapies.

Harnessing deep learning into hidden mutations of neurological disorders for therapeutic challenges

The relevant study of transcriptome-wide variations and neurological disorders in the evolved field of genomic data science is on the rise. Deep learning has been highlighted utilizing algorithms on massive amounts of data in a human-like manner, and is expected to predict the dependency or druggability of hidden mutations within the genome. Enormous mutational variants in coding and noncoding transcripts have been discovered along the genome by far, despite of the fine-tuned genetic proofreading machinery. These variants could be capable of inducing various pathological conditions, including neurological disorders, which require lifelong care. Several limitations and questions emerge, including the use of conventional processes via limited patient-driven sequence acquisitions and decoding-based inferences as well as how rare variants can be deduced as a population-specific etiology. These puzzles require harnessing of advanced systems for precise disease prediction, drug development and drug applications. In this review, we summarize the pathophysiological discoveries of pathogenic variants in both coding and noncoding transcripts in neurological disorders, and the current advantage of deep learning applications. In addition, we discuss the challenges encountered and how to outperform them with advancing interpretation.

Homologous recombination deficiency signatures in gastrointestinal and thoracic cancers correlate with platinum therapy duration

There is emerging evidence about the predictive role of homologous recombination deficiency (HRD), but this is less defined in gastrointestinal (GI) and thoracic malignancies. We reviewed whole genome (WGS) and transcriptomic (RNA-Seq) data from advanced GI and thoracic cancers in the Personalized OncoGenomics trial (NCT02155621) to evaluate HRD scores and single base substitution (SBS)3, which is associated with BRCA1/2 mutations and potentially predictive of defective HRD. HRD scores were calculated by sum of loss of heterozygosity, telomeric allelic imbalance, and large-scale state transitions scores. Regression analyses examined the association between HRD and time to progression on platinum (TTPp). We included 223 patients with GI (n = 154) or thoracic (n = 69) malignancies. TTPp was associated with SBS3 (p < 0.01) but not HRD score in patients with GI malignancies, whereas neither was associated with TTPp in thoracic malignancies. Tumors with gBRCA1/2 mutations and a somatic second alteration exhibited high SBS3 and HRD scores, but these signatures were also present in several tumors with germline but no somatic second alterations, suggesting silencing of the wild-type allele or BRCA1/2 haploinsufficiency. Biallelic inactivation of an HR gene, including loss of XRCC2 and BARD1, was identified in BRCA1/2 wild-type HRD tumors and these patients had prolonged response to platinum. Thoracic cases with high HRD score were associated with high RECQL5 expression (p ≤ 0.025), indicating another potential mechanism of HRD. SBS3 was more strongly associated with TTPp in patients with GI malignancies and may be complementary to using HRD and BRCA status in identifying patients who benefit from platinum therapy.

Transcriptomic Approach for Global Distribution of SNP/Indel and Plant Genotyping

Single Nucleotide Polymorphisms (SNPs) are the most common structural variants found in any genome. They have been used for different genetic studies, from the understanding of genetic structure of populations to the development of breeding selection markers. In this chapter we present the use of transcriptomic data obtained from contrasting phenotypes for a target trait, in searching of SNPs and insertions/deletions (InDels). This approach has the advantage that the identified markers are in or close to differentially expressed genes, and so they have higher chances to tag the genes underlying the phenotypic expression of a particular trait.

The clinical utility of integrative genomics in childhood cancer extends beyond targetable mutations

We conducted integrative somatic-germline analyses by deeply sequencing 864 cancer-associated genes, complete genomes and transcriptomes for 300 mostly previously treated children and adolescents/young adults with cancer of poor prognosis or with rare tumors enrolled in the SickKids Cancer Sequencing (KiCS) program. Clinically actionable variants were identified in 56% of patients. Improved diagnostic accuracy led to modified management in a subset. Therapeutically targetable variants (54% of patients) were of unanticipated timing and type, with over 20% derived from the germline. Corroborating mutational signatures (SBS3/BRCAness) in patients with germline homologous recombination defects demonstrates the potential utility of PARP inhibitors. Mutational burden was significantly elevated in 9% of patients. Sequential sampling identified changes in therapeutically targetable drivers in over one-third of patients, suggesting benefit from rebiopsy for genomic analysis at the time of relapse. Comprehensive cancer genomic profiling is useful at multiple points in the care trajectory for children and adolescents/young adults with cancer, supporting its integration into early clinical management.

Progress in precision therapy in pediatric oncology

PURPOSE OF REVIEW

The fields of precision medicine and cancer genomics in pediatric oncology are rapidly evolving. Novel diagnostic tools are critical in refining cancer diagnoses, stratifying patient risk, and informing treatment decisions. This review is timely and relevant as it discusses advantages and drawbacks of common molecular profiling techniques and highlights novel platforms, which may address select limitations. We discuss recent publications demonstrating utility of large-scale molecular profiling and feasibility and logistics of matching targeted therapies to patients.

RECENT FINDINGS

We describe the increased accessibility of next-generation sequencing, complementary profiling methods, and strategies to guide treatment decisions. We describe curation and sharing of large genomic datasets and novel mechanisms to obtain matched targeted therapies. Importantly, we discuss relevant publications in distinct disease domains that support indications for evidence-based precision therapy. Lastly, we introduce the incremental analyses that can be obtained via whole-genome and transcriptome sequencing.

SUMMARY

Here we highlight high-yield clinical scenarios of precision medicine approaches and identify the ongoing challenges including universally defining clinical actionability, optimizing trial design to account for molecular heterogeneity while acknowledging limitations in patient accrual, expanding access to molecularly targeted therapies, and validating new tools and technology to aid in precision medicine therapeutic approaches.

Subclonal somatic copy number alterations emerge and dominate in recurrent osteosarcoma

Multiple large-scale tumor genomic profiling efforts have been undertaken in osteosarcoma, however, little is known about the spatial and temporal intratumor heterogeneity and how it may drive treatment resistance. We performed whole-genome sequencing of 37 tumor samples from eight patients with relapsed or refractory osteosarcoma. Each patient had at least one sample from a primary site and a metastatic or relapse site. We identified subclonal copy number alterations in all but one patient. We observed that in five patients, a subclonal copy number clone from the primary tumor emerged and dominated at subsequent relapses. MYC gain/amplification was enriched in the treatment-resistant clone in 6 out of 7 patients with more than one clone. Amplifications in other potential driver genes, such as CCNE1, RAD21, VEGFA, and IGF1R, were also observed in the resistant copy number clones. Our study sheds light on intratumor heterogeneity and the potential drivers of treatment resistance in osteosarcoma.

Therapeutic Targeting of ALK in Neuroblastoma: Experience of Italian Precision Medicine in Pediatric Oncology

Neuroblastoma (NB) is the most common extracranial solid tumor in childhood. Patients with relapsed/refractory disease have a poor prognosis, and additional therapeutic options are needed. Mutations and amplifications in the ALK (Anaplastic Lymphoma Kinase) gene constitute a key target for treatment. Our goal, within the Italian project of PeRsonalizEdMEdicine (PREME), was to evaluate the genomic status of patients with relapsed/refractory NB and to implement targeted therapies in those with targetable mutations. From November 2018 to November 2021, we performed Whole Exome Sequencing or Targeted Gene Panel Sequencing in relapsed/refractory NB patients in order to identify druggable variants. Activating mutations of ALK were identified in 8(28.57%) of 28 relapsed/refractory NB patients. The mutation p.F1174L was found in six patients, whereas p.R1275Q was found in one and the unknown mutation p.S104R in another. Three patients died before treatment could be started, while five patients received crizotinib: two in monotherapy (one with p.F1174L and the other with p.S104R) and three (with p.F1174L variant) in combination with chemotherapy. All treated patients showed a clinical improvement, and one had complete remission after two cycles of combined treatment. The most common treatment-related toxicities were hematological. ALK inhibitors may play an important role in the treatment of ALK-mutated NB patients.

Risk stratifying MDS in the time of precision medicine

Myelodysplastic syndromes (MDS) are myeloid neoplasms characterized by morphologic dysplasia, persistent cytopenia, and a variable risk of evolution to acute myeloid leukemia (AML). Risk stratification is crucial in a patient-centered approach to the treatment of MDS. Based on hematologic parameters and cytogenetic abnormalities, the Revised International Prognostic Scoring System is currently used for this purpose. In the past years, the use of massively parallel DNA sequencing has clarified the genetic basis of MDS and has enabled development of novel diagnostic and prognostic approaches. When conventional cytogenetics is combined with gene sequencing, more than 90% of patients are found to carry a somatic genetic lesion. In addition, a portion of patients has germline variants that predispose them to myeloid neoplasms. The recently developed International Consensus Classification of MDS includes new entities that are molecularly defined-namely, SF3B1-mutant and TP53-mutant MDS. The International Working Group for Prognosis in MDS has just developed the International Prognostic Scoring System-Molecular (IPSS-M) for MDS, which considers hematologic parameters, cytogenetic abnormalities, and somatic gene mutations. The IPSS-M score is personalized and can be obtained using a web-based calculator that returns not only the individual score but also the expected leukemia-free survival, overall survival, and risk of AML transformation. Providing an efficient risk stratification of patients with MDS, the IPSS-M represents a valuable tool for individual risk assessment and treatment decisions.

Implementation of Whole-Genome and Transcriptome Sequencing Into Clinical Cancer Care

PURPOSE

The combination of whole-genome and transcriptome sequencing (WGTS) is expected to transform diagnosis and treatment for patients with cancer. WGTS is a comprehensive precision diagnostic test that is starting to replace the standard of care for oncology molecular testing in health care systems around the world; however, the implementation and widescale adoption of this best-in-class testing is lacking.

METHODS

Here, we address the barriers in integrating WGTS for cancer diagnostics and treatment selection and answer questions regarding utility in different cancer types, cost-effectiveness and affordability, and other practical considerations for WGTS implementation.

RESULTS

We review the current studies implementing WGTS in health care systems and provide a synopsis of the clinical evidence and insights into practical considerations for WGTS implementation. We reflect on regulatory, costs, reimbursement, and incidental findings aspects of this test.

CONCLUSION

WGTS is an appropriate comprehensive clinical test for many tumor types and can replace multiple, cascade testing approaches currently performed. Decreasing sequencing cost, increasing number of clinically relevant aberrations and discovery of more complex biomarkers of treatment response, should pave the way for health care systems and laboratories in implementing WGTS into clinical practice, to transform diagnosis and treatment for patients with cancer.

The role of next-generation sequencing in acute myeloid leukemia

PURPOSE OF REVIEW

The development of high-throughput techniques like next-generation sequencing (NGS) has unraveled the genetic profile of cancer. In this review, we discuss the role of NGS on the diagnostic, risk stratification, and follow-up of patients with acute myeloid leukemia (AML).

RECENT FINDINGS

NGS has become an essential tool in clinical practice for AML management. Therefore, efforts are being made to improve its applications, automation, and turnaround time. Other high-throughput techniques, such as whole genome sequencing or RNA-sequencing, can be also used to this end. However, not all institutions may be able to implement these approaches. NGS is being investigated for measurable residual disease (MRD) assessment, especially with the development of error-correction NGS. New data analysis approaches like machine learning are being investigated in order to integrate genomic and clinical data and develop comprehensive classifications and risk scores.

SUMMARY

NGS has proven to be a useful approach for the analysis of genomic alterations in patients with AML, which aids patient management. Current research is being directed at reducing turnaround time and simplifying processes so that these techniques can be universally integrated into clinical practice.

Pediatric precision oncology-Time for clinical prime time

Recent prospective molecular tumor-profiling studies in pediatric cancer patients across a variety of different healthcare systems have highlighted both the feasibility and clinical utility of this approach. The current study by Church and colleagues in Nature Medicine¹ has further substantiated this and laid the groundwork for a systematic collaborative approach to pediatric precision oncology in the US.