Integrated genomic DNA/RNA profiling of hematologic malignancies in the clinical setting.

The spectrum of somatic alterations in hematologic malignancies includes substitutions, insertions/deletions (indels), copy number alterations (CNAs), and a wide range of gene fusions; no current clinically available single assay captures the different types of alterations. We developed a novel next-generation sequencing-based assay to identify all classes of genomic alterations using archived formalin-fixed paraffin-embedded blood and bone marrow samples with high accuracy in a clinically relevant time frame, which is performed in our Clinical Laboratory Improvement Amendments-certified College of American Pathologists-accredited laboratory. Targeted capture of DNA/RNA and next-generation sequencing reliably identifies substitutions, indels, CNAs, and gene fusions, with similar accuracy to lower-throughput assays that focus on specific genes and types of genomic alterations. Profiling of 3696 samples identified recurrent somatic alterations that impact diagnosis, prognosis, and therapy selection. This comprehensive genomic profiling approach has proved effective in detecting all types of genomic alterations, including fusion transcripts, which increases the ability to identify clinically relevant genomic alterations with therapeutic relevance.

Comprehensive Genomic Profiling of Advanced Penile Carcinoma Suggests a High Frequency of Clinically Relevant Genomic Alterations.

BACKGROUND: Advanced penile squamous cell carcinoma (PSCC) is associated with poor survival due to the aggressiveness of the disease and lack of effective systemic therapies. Comprehensive genomic profiling (CGP) was performed to identify clinically relevant genomic alterations (CRGAs). MATERIALS AND METHODS: DNA was extracted from 40 µm of formalin-fixed, paraffin-embedded sections in patients with advanced PSCC. CGP was performed on hybridization-captured, adaptor ligation-based libraries to a mean coverage depth of 692× for 3,769 exons of 236 cancer-related genes plus 47 introns from 19 genes frequently rearranged in cancer. CRGAs were defined as genomic alterations (GAs) linked to targeted therapies on the market or under evaluation in mechanism-driven clinical trials. RESULTS: Twenty male patients with a median age of 60 years (range, 46-87 years) were assessed. Seventeen (85%) cases were stage IV and three cases (15%) were stage III. CGP revealed 109 GAs (5.45 per tumor), 44 of which were CRGAs (2.2 per tumor). At least one CRGA was detected in 19 (95%) cases, and the most common CRGAs were CDKN2A point mutations and homozygous deletion (40%), NOTCH1 point mutations and rearrangements (25%), PIK3CA point mutations and amplification (25%), EGFR amplification (20%), CCND1 amplification (20%), BRCA2 insertions/deletions (10%), RICTOR amplifications (10%), and FBXW7 point mutations (10%). CONCLUSION: CGP identified CRGAs in patients with advanced PSCC, including EGFR amplification and PIK3CA alterations, which can lead to the rational administration of targeted therapy and subsequent benefit for these patients. IMPLICATIONS FOR PRACTICE: Few treatment options exist for patients with advanced penile squamous cell carcinoma (PSCC). Outcomes are dismal with platinum-based chemotherapy, with median survival estimated at 1 year or less across multiple series. Biological studies of patients with PSCC to date have principally focused on human papillomavirus status, but few studies have elucidated molecular drivers of the disease. To this end, comprehensive genomic profiling was performed in a cohort of 20 patients with advanced PSCC. Findings of frequent mutations in CDKN2A, NOTCH1, PIK3CA, and EGFR (all in excess of 20%) point to potential therapeutic avenues. Trials of targeted therapies directed toward these mutations should be explored.

Development and validation of a clinical cancer genomic profiling test based on massively parallel DNA sequencing.

As more clinically relevant cancer genes are identified, comprehensive diagnostic approaches are needed to match patients to therapies, raising the challenge of optimization and analytical validation of assays that interrogate millions of bases of cancer genomes altered by multiple mechanisms. Here we describe a test based on massively parallel DNA sequencing to characterize base substitutions, short insertions and deletions (indels), copy number alterations and selected fusions across 287 cancer-related genes from routine formalin-fixed and paraffin-embedded (FFPE) clinical specimens. We implemented a practical validation strategy with reference samples of pooled cell lines that model key determinants of accuracy, including mutant allele frequency, indel length and amplitude of copy change. Test sensitivity achieved was 95-99% across alteration types, with high specificity (positive predictive value >99%). We confirmed accuracy using 249 FFPE cancer specimens characterized by established assays. Application of the test to 2,221 clinical cases revealed clinically actionable alterations in 76% of tumors, three times the number of actionable alterations detected by current diagnostic tests.