The Clinical Utility of a Tiered Approach to Pediatric Glioma Molecular Characterization for Resource-Limited Settings.

PURPOSE: Molecular characterization is key to optimally diagnose and manage cancer. The complexity and cost of routine genomic analysis have unfortunately limited its use and denied many patients access to precision medicine. A possible solution is to rationalize use-creating a tiered approach to testing which uses inexpensive techniques for most patients and limits expensive testing to patients with the highest needs. Here, we tested the utility of this approach to molecularly characterize pediatric glioma in a cost- and time-sensitive manner. METHODS: We used a tiered testing pipeline of immunohistochemistry (IHC), customized fusion panels or fluorescence in situ hybridization (FISH), and targeted RNA sequencing in pediatric gliomas. Two distinct diagnostic algorithms were used for low- and high-grade gliomas (LGGs and HGGs). The percentage of driver alterations identified, associated testing costs, and turnaround time (TAT) are reported. RESULTS: The tiered approach successfully characterized 96% (95 of 99) of gliomas. For 82 LGGs, IHC, targeted fusion panel or FISH, and targeted RNA sequencing solved 35% (29 of 82), 29% (24 of 82), and 30% (25 of 82) of cases, respectively. A total of 64% (53 of 82) of samples were characterized without targeted RNA sequencing. Of 17 HGG samples, 13 were characterized by IHC and four were characterized by targeted RNA sequencing. The average cost per sample was more affordable when using the tiered approach as compared with up-front targeted RNA sequencing in LGG ($405 US dollars [USD] v $745 USD) and HGGs ($282 USD v $745 USD). The average TAT per sample was also shorter using the tiered approach (10 days for LGG, 5 days for HGG v 14 days for targeted RNA sequencing). CONCLUSION: Our tiered approach molecularly characterized 96% of samples in a cost- and time-sensitive manner. Such an approach may be feasible in neuro-oncology centers worldwide, particularly in resource-limited settings.

Next-Generation Sequencing Panel for 1p/19q Codeletion and IDH1-IDH2 Mutational Analysis Uncovers Mistaken Overdiagnoses of 1p/19q Codeletion by FISH.

The 1p/19q codeletion is the result of a translocation between chromosome 1 (Chr1p) and chromosome 19 (Chr19q) with the loss of derivative (1;19)(p10;q10) chromosome. The 1p/19q codeletion has predictive and prognostic significance, and it is essential for the classification of gliomas. In routine practice, the fluorescence in situ hybridization (FISH) diagnosis of 1p/19q codeletion is sometimes unexpected. This study aimed to develop a next-generation sequencing panel for the concurrent definition of the 1p/19q codeletion and IDH1/IDH2 mutation status to resolve these equivocal cases. A total of 65 glioma samples were investigated using a 1p/19q-single-nucleotide polymorphism (SNP)-IDH panel. The panel consists of 192 amplicons, including SNPs mapping to Chr1 and Chr19 and amplicons for IDH1/IDH2 analysis. The 1p/19q SNP-IDH panel consistently identified IDH1/IDH2 mutations. In 49 of 60 cases (81.7%), it provided the same 1p/19q results obtained by FISH. In the remaining 11 cases, the 1p/19q SNP-IDH panel uncovered partial chromosome imbalances as a result of interstitial amplification or deletion of the regions where the FISH probes map, leading to a mistaken overdiagnosis of 1p/19q codeletion by FISH. The 1p/19q SNP-IDH next-generation sequencing panel allows reliable analysis of the 1p/19q codeletion and IDH1/IDH2 mutation at the same time. The panel not only allows resolution of difficult cases but also represents a cost-effective alternative to standard molecular diagnostics procedures.

Prenatal diagnosis of BACs-on-Beads assay in 1520 cases from Fujian Province, China.

BACKGROUND: The aim of this study was to evaluate the application of BACs-on-Beads (BoBs™) assay for rapid detection of chromosomal abnormalities for prenatal diagnosis (PND). METHODS: A total of 1520 samples, including seven chorionic villi biopsy samples, 1328 amniotic fluid samples, and 185 umbilical cord samples from pregnant women were collected to detect the chromosomal abnormalities using BoBs™ assay and karyotyping. Furthermore, abnormal specimens were verified by chromosome microarray analysis (CMA) and fluorescence in situ hybridization (FISH). RESULTS: The results demonstrated that the success rate of karyotyping and BoBs™ assay in PND was 98.09% and 100%, respectively. BoBs™ assay was concordant with karyotyping for Trisomy 21, Trisomy 18, and Trisomy 13, sex chromosomal aneuploidy, Wolf-Hirschhorn syndrome, and mosaicism. BoBs™ assay also detected Smith-Magenis syndrome, Williams-Beuren syndrome, DiGeorge syndrome, Miller-Dieker syndrome, Prader-Willi syndrome, Xp22.31 microdeletions, 22q11.2, and 17p11.2 microduplications. However, karyotyping failed to show these chromosomal abnormalities. A case of 8q21.2q23.3 duplication which was found by karyotyping was not detected by BoBs™ assay. Furthermore, all these chromosomal abnormalities were consistent with CMA and FISH verifications. According to the reports, we estimated that the detection rates of karyotyping, BoBs™, and CMA in the present study were 4.28%, 4.93%, and 5%, respectively, which is consistent with the results of a previous study. The respective costs for the three methods were about $135-145, $270-290, and $540-580. CONCLUSION: BoBs™ assay is considered a reliable, rapid test for use in PND. A variety of comprehensive technological applications can complement each other in PND, in order to maximize the diagnosis rate and reduce the occurrence of birth defects.

Development and Evaluation of a Pan-Sarcoma Fusion Gene Detection Assay Using the NanoString nCounter Platform.

The NanoString nCounter assay is a high-throughput hybridization technique using target-specific probes that can be customized to test for numerous fusion transcripts in a single assay using RNA from formalin-fixed, paraffin-embedded material. We designed a NanoString assay targeting 174 unique fusion junctions in 25 sarcoma types. The study cohort comprised 212 cases, 96 of which showed fusion gene expression by the NanoString assay, including all 20 Ewing sarcomas, 11 synovial sarcomas, and 5 myxoid liposarcomas tested. Among these 96 cases, 15 showed fusion expression not identified by standard clinical assay, including EWSR1-FLI1, EWSR1-ERG, BCOR-CCNB3, ZC3H7B-BCOR, HEY1-NCOA2, CIC-DUX4, COL1A1-PDGFB, MYH9-USP6, YAP1-TFE3, and IRF2BP2-CDX1 fusions. There were no false-positive results; however, four cases were false negative when compared with clinically available fluorescence in situ hybridization or RT-PCR testing. When batched as six cases, the per-sample reagent cost was less than conventional techniques, such as fluorescence in situ hybridization, with technologist hands-on time of 1.2 hours per case and assay time of 36 hours. In summary, the NanoString nCounter Sarcoma Fusion CodeSet reliably and cost-effectively identifies fusion genes in sarcomas using formalin-fixed, paraffin-embedded material, including many fusions missed by standard clinical assays, and can serve as a first-line clinical diagnostic test for sarcoma fusion gene identification, replacing multiple individual clinical assays.

Clinical and Cost Implications of Universal Versus Locally Advanced-Stage and Advanced-Stage-Only Molecular Testing for Epidermal Growth Factor Receptor Mutations and Anaplastic Lymphoma Kinase Rearrangements in Non-Small Cell Lung Carcinoma: A Tertiary Academic Institution Experience.

CONTEXT: Although epidermal growth factor receptor (EGFR)- and anaplastic lymphoma kinase (ALK)-directed therapies are not approved for patients with early-stage non-small cell lung carcinoma (NSCLC), many institutions perform EGFR and ALK testing for all patients with NSCLC at the time of initial diagnosis. Current consensus guidelines recommend EGFR testing and suggest ALK testing at the time of initial diagnosis for patients with advanced disease. OBJECTIVES: To examine the cost and clinical impact of EGFR and ALK testing of patients with early-stage NSCLC. DESIGN: Records from all patients with a diagnosis of NSCLC made on a nonresection specimen at our institution during a single calendar year (2012) were reviewed, and a cost analysis was performed. RESULTS: Of 133 total patients, 47 (35%) had early-stage (stage I or II) disease and 86 (65%) had locally advanced (stage III) or advanced (stage IV) disease at presentation. Eight of 47 patients with early-stage disease (17%) had progression/recurrence during 18 to 30 months of follow-up, 6 of 8 (75%) of whom had pathologic confirmation of progression/recurrence. The estimated additional cost of EGFR and ALK testing for all newly diagnosed patients with NSCLC at our institution is $75,200 per year, compared to testing only patients with locally advanced and advanced-stage disease. CONCLUSIONS: The cost of universal molecular testing of NSCLC is substantial. EGFR and ALK testing of patients with early-stage disease appears to have negligible clinical impact, as most patients do not have disease recurrence/progression. Those whose disease recurs/progresses typically undergo rebiopsy. Our findings do not support the practice of universal EGFR and ALK testing in NSCLC at the time of initial diagnosis.

Tissue Microarrays.

Modern next-generation sequencing and microarray technologies allow for the simultaneous analysis of all human genes on the DNA, RNA, miRNA, and methylation RNA level. Studies using such techniques have lead to the identification of hundreds of genes with a potential role in cancer or other diseases. The validation of all of these candidate genes requires in situ analysis of high numbers of clinical tissues samples. The tissue microarray technology greatly facilitates such analysis. In this method minute tissue samples (typically 0.6 mm in diameter) from up to 1000 different tissues can be analyzed on one microscope glass slide. All in situ methods suitable for histological studies can be applied to TMAs without major changes of protocols, including immunohistochemistry, fluorescence in situ hybridization, or RNA in situ hybridization. Because all tissues are analyzed simultaneously with the same batch of reagents, TMA studies provide an unprecedented degree of standardization, speed, and cost efficiency.

A multistep cytological approach for patients with jaundice and biliary strictures of indeterminate origin.

AIMS: Fluorescence in situ hybridisation (FISH) increases the sensitivity for detecting pancreatobiliary tract cancer over routine cytology. In this study, diagnostic accuracy and costs of cytology and FISH in detecting cancer in patients with jaundice with biliary strictures were assessed. METHODS: Brushing specimens from 109 patients with jaundice were obtained during endoscopic retrograde cholangiopancreatography and examined by cytology and FISH. The specimens were considered FISH-positive for malignancy if at least five polysomic cells or 10 cells with homozygous or heterozygous 9p21/p16 deletion were detected. Definitive diagnosis of the stricture as benign or malignant relied on surgical pathology (45 cases) or clinical-radiological follow-up >18 months (64 cases). We calculated costs of cytology and FISH based on the reimbursement from the Piedmont region, Italy (respectively, €33 and €750). RESULTS: Ninety of 109 patients had evidence of malignancy (44 pancreatic carcinomas, 36 cholangiocarcinomas, 5 gallbladder carcinomas, 5 other cancers), while 19 had benign strictures. Routine cytology showed 42% sensitivity, but 100% specificity for the diagnosis of malignancy, while FISH-polysomy showed 70% sensitivity with 100% specificity and FISH-polysomy plus homozygous or heterozygous 9p21/p16 deletion showed 76% sensitivity with 100% specificity. The cost per additional correct diagnosis of cancer obtained by FISH, in comparison with cytology, was €1775 using a sequential cytological approach (ie, performing FISH only in patients with negative or indeterminate cytology). CONCLUSIONS: FISH should be recommended as the second step in detecting cancer in patients with jaundice with pancreatobiliary tract strictures and cytology negative or indeterminate for malignancy.

Reagent and labor cost optimization through automation of fluorescence in situ hybridization (FISH) with the VP 2000: an Italian case study.

In the modern molecular diagnostic laboratory, cost considerations are of paramount importance. Automation of complex molecular assays not only allows a laboratory to accommodate higher test volumes and throughput but also has a considerable impact on the cost of testing from the perspective of reagent costs, as well as hands-on time for skilled laboratory personnel. The following study tracked the cost of labor (hands-on time) and reagents for fluorescence in situ hybridization (FISH) testing in a routine, high-volume pathology and cytogenetics laboratory in Treviso, Italy, over a 2-y period (2011-2013). The laboratory automated FISH testing with the VP 2000 Processor, a deparaffinization, pretreatment, and special staining instrument produced by Abbott Molecular, and compared hands-on time and reagent costs to manual FISH testing. The results indicated significant cost and time saving when automating FISH with VP 2000 when more than six FISH tests were run per week. At 12 FISH assays per week, an approximate total cost reduction of 55% was observed. When running 46 FISH specimens per week, the cost saving increased to 89% versus manual testing. The results demonstrate that the VP 2000 processor can significantly reduce the cost of FISH testing in diagnostic laboratories.

FISH for 22q11.2 deletion not cost-effective for infants with congenital heart disease with microarray.

The objective of this study is to evaluate the yield of genetic testing in infants with congenital heart disease, who undergo surgical intervention prior to one year of age, and develop a cost-effective strategy to screen infants with congenital heart disease for genetic conditions while providing standard of care. 409 charts of patients with congenital heart disease, who underwent surgical intervention prior to one year of age, were retrospectively reviewed for cytogenetic testing results. 278 patients underwent cytogenetic testing, and 89.6 % of these patients had more than one cytogenetic test completed. The most commonly encountered chromosomal anomaly within the sample was Down Syndrome (12.5 %), followed by 22q11.2 Deletion Syndrome (4.6 %). G-Banded Karyotypes were abnormal in 10.5 % of patients, fluorescence in situ hybridization (FISH) probe for 22q11.2 deletion was abnormal in 7.1 % of patients. SNP microarray testing showed the highest yield and was abnormal in 33 % of patients. Based on the data at our institution, a more directed approach of genetic screening with only microarray would have saved our institution approximately $101, 200 on the 103 patients who underwent genetic evaluation with microarray reviewed. Screening infants with congenital heart disease for 22q11.2 deletion with FISH resulted in a loss of approximately $32,000 per 100 patients at our institution. Institutions should develop microarray-based protocols for genetic screening in patients with congenital heart disease with the anticipation of adding lesion-specific single gene testing as single gene testing becomes routinely available.

FHACT: the FISH-based HPV-associated cancer test that detects nonrandom gain at four genomic loci as biomarkers of disease progression.

Despite implementation of screening programs for human papillomavirus (HPV)-associated cancers, in particular cervical, scientific studies continue to uncover viral and host biomarkers that could serve to further optimize the detection of individuals with underlying or at risk for developing precancer or cancer. Nonrandom host somatic chromosomal alterations are frequently shared across HPV-associated cancers, but with varying frequencies, potentially with functional roles. At least for 3q26 gain, there is firm preliminary evidence to support that this genomic alteration can serve as a biomarker of disease progression of cervical cancer. In the current review, the FISH-based HPV-associated cancer test is described that enables detection of genomic imbalance at four loci (3q26, 5p15, 20q13, centromere 7) in a single hybridization on a cell-by-cell basis in cytology specimens. When implemented as a secondary screening assay, the FISH-based HPV-associated cancer test could assist in the detection of clinically relevant HPV-associated disease and help guide patient management decisions.

Accurate and economical detection of ALK positive lung adenocarcinoma with semiquantitative immunohistochemical screening.

Right detection of anaplastic lymphoma kinase (ALK) gene rearrangement is pivotal to selection of patients with lung adenocarcinoma for ALK-targeted therapy. We explored the potential of combination of immunohistochemistry (IHC) screening and fluorescence in situ hybridization (FISH) as an affordable practice. We analyzed 410 unselected lung adenocarcinomas by ALK IHC (D5F3 clone) and FISH. Some equivocal cases were further analyzed by RT-PCR. The EGFR mutation was detected by pyrosequencing assay. In total 368 cases which got all IHC, FISH, EGFR mutation results were eligible for analysis. Cases were evaluated as IHC score 3+ (n = 26), score 2+ (n = 9), score 1+ (n = 51), and score 0 (n = 282), respectively. 23 of 26 IHC 3+ and 5 of 9 IHC 2+ cases were FISH positive, whereas 3 of 26 IHC 3+, 4 of 9 IHC 2+ and all 333 IHC 1+/0 cases were FISH negative. If considering FISH as the standard, the sensitivity and specificity of ALK IHC 3+/2+ as ALK positive were 100% and 97.9%, respectively. Three IHC 3+ cases reported as FISH "negative" were actually ALK positive confirmed by ALK RT-PCR or re-detected. Based on the final classify, ALK IHC 3+/2+ was 100% sensitive and 98.8% specific. However, FISH was 90.3% sensitive and 100% specific. IHC 2+ was regarded as equivocal and need to be confirmed by FISH or RT-PCR. In the 368 cases, 8.4% cases had ALK positive, 52.2% cases had EGFR mutation, and only one case had a coexisting. Manually semiquantitative ALK IHC (primary antibody D5F3 coupled with secondary DAKO Envision system) used as the initial screening combined with auxiliary FISH confirmation is a reliable, economical approach to identify ALK positive lung adenocarcinoma. The IHC can find some ALK positive cases which would be missed by FISH only.

Limited human epidermal growth factor receptor 2 discordance in metastatic breast cancer patients treated with trastuzumab, a population based study.

BACKGROUND: Accurate assessment of the human epidermal growth factor receptor 2 (HER2) in breast cancer is essential for proper treatment decisions. HER2 positivity confirmation rates in breast cancer trials by central testing pathology laboratories were reported to be approximately 85%. The aim of our study was to assess in a population based sample concordance of HER2 status in metastatic breast cancer (MBC) patients locally tested HER2 positive and treated with trastuzumab. Moreover cost-effectiveness of in situ hybridisation (ISH) in patients with an immunohistochemical score 3+ (IHC3+) was explored. METHODS: MBC patients treated between 2005 and 2009 with trastuzumab-based therapy in North East Netherlands were identified by a survey of hospital pharmacies. Primary tumour samples were retested centrally for HER2 status using 1 immunohistochemical (IHC) method and two methods using ISH on tissue micro-arrays. Potential discordant patients were retested on whole tumour slides. HER2 positivity was defined as: (1) ISH amplification (according to American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) clinical practice Guideline Update) and (2) when ISH failed an IHC score of 3+. Cost-effectiveness was estimated using potential ISH and treatment costs. RESULTS: HER2 status could be retested in 174 of 194 (90%) patients. The HER2 concordance rate was 87%. The 21 discordant patients were in the 67% due to primary HER2 testing with only IHC. Overall survival of HER2 discordant and concordant patients was not significantly different (18 versus 25months, p=0.131). Structural ISH in the case of IHC3+ has an estimated potential saving of €87,710 per 100 patients. CONCLUSION: HER2 concordance in a population based study is comparable to those described in selected populations. Discordance is mostly due to testing with only IHC. ISH in the case of IHC3+ is cost-effective.

[Comparative cost analysis of molecular biology methods in the diagnosis of sarcomas]. / Analyse comparative des coûts de techniques de biologie moléculaire dans le diagnostic de sarcomes.

Sarcomas represent a complex and heterogeneous group of rare malignant tumors and their correct diagnosis is often difficult. Recent molecular biological techniques have been of great diagnostic use and there is a need to assess the cost of these procedures in routine clinical practice. Using prospective and observational data from eight molecular biology laboratories in France, we used "microcosting" method to assess the cost of molecular biological techniques in the diagnosis of five types of sarcoma. The mean cost of fluorescence in situ hybridization (FISH) was 318 € (273-393) per sample; mean reverse transcription polymerase chain reaction (RT-PCR) cost ranged from 300 € (229-481) per formalin-fixed, paraffin-embedded specimen to 258 € (213-339) per frozen specimen; mean quantitative polymerase chain reaction (Q-PCR) cost was 184 € (112-229) and mean CGH-array cost was 332 € (329-335). The cost of these recently implemented techniques varied according to the type of sarcoma; the method of tissue collection and local organizational factors including the level of local expertise and investment. The cost of molecular diagnostic techniques needs to be balanced against their respective performance.

[Comparative evaluation of the predictive value of UroVysion and AURKA FISH tests of urine sediment cells for the diagnosis of bladder cancer].

Informative value of two tests based on FISH of exfoliated urothelial cells in urine sediment (AURKA and UroVysion) was compared in the group of patients (31 persons) with the history of bladder cancer. Coincidence in results of both FISH assays was found in 93.5%. These preliminary data offer the possibility of replacing the expensive UroVysion kit by the less expensive AURKA FISH probe and it could be used for monitoring of recurrence in bladder cancer patients.

Assessing the potential cost-effectiveness of retesting IHC0, IHC1+, or FISH-negative early stage breast cancer patients for HER2 status.

BACKGROUND: Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) tests are commonly used to assess human epidermal growth factor 2 (HER2) status of tumors in patients with breast cancer. This analysis evaluates the likely cost-effectiveness of expanded retesting to assess HER2 tumor status in women with early stage breast cancer. METHODS: We developed a decision-analytic model to estimate the incremental cost-effectiveness ratio (ICER) of expanded reflex testing from a US payer perspective. Expanded reflex testing is defined as retesting tumor specimens from patients whose tumors are IHC0, IHC1+, or FISH-negative on their first test. In the base case, we assumed that 80% of patient tumors are initially IHC-tested and 20% are FISH-tested. Testing outcomes for IHC and FISH with and without retesting were based on published meta-analyses. The cost of tests and treatment and the long-term health outcomes were obtained from the literature. RESULTS: In the base case, we estimated that 2.27% of women who received expanded reflex testing would be HER2-positive and receive trastuzumab treatment: the projected ICER was $36,721 per life year or $39,745 per quality-adjusted life year (QALY). This varied between $47,100 per QALY and $35,500 per QALY if we assumed that 1%-8% of patients retested were then HER2+, respectively. The results of deterministic and probabilistic sensitivity analysis were robust. This strategy would result in 4700 (2000-17,000) patients being eligible to receive trastuzumab treatment annually. CONCLUSIONS: Retesting patients who are IHC0, IHC1+, or FISH-negative is projected to be a cost-effective clinical strategy.

Cost-effectiveness of a FISH assay for the diagnosis of melanoma in the USA.

OBJECTIVE: The authors evaluated the cost-effectiveness of a FISH assay in melanoma diagnosis in the USA. METHOD: A model was developed simulating the addition of FISH to the diagnosis of suspected melanoma. A decision analytic module simulated diagnosis using microscopic assessment alone versus addition of FISH (sensitivity: 92%; specificity: 94%). The authors simulated a clinical setting in which an initial excisional biopsy microscopic assessment (sensitivity: 73%; specificity: 78%) was followed by dermatopathologist assessment (sensitivity: 89%; specificity: 79%) for inconclusive results. Diagnostic strategies 1 and 2 added FISH to the initial and dermatopathologist assessments, respectively. A Markov outcomes module simulated patients' remaining lifetime, including treatment. RESULTS: In diagnostic strategies 1 and 2, the cost per quality-adjusted life year gained was US$14,930 and 43,925, respectively, versus no FISH. Cost per misdiagnosis avoided was US$3292 and 3759, respectively. Sensitivity and specificity without FISH were both ≥88%; however, addition of FISH exceeded US$100,000/quality-adjusted life year. CONCLUSION: In specific clinical settings, FISH could be cost effective for melanoma diagnosis.