30 research outputs found
Micro-costing diagnostics in oncology:from single-gene testing to whole- genome sequencing
Purpose: Predictive diagnostics play an increasingly important role in personalized medicine for cancer treatment. Whole-genome sequencing (WGS)-based treatment selection is expected to rapidly increase worldwide. This study aimed to calculate and compare the total cost of currently used diagnostic techniques and of WGS in treatment of non-small cell lung carcinoma (NSCLC), melanoma, colorectal cancer (CRC), and gastrointestinal stromal tumor (GIST) in the Netherlands. Methods: The activity-based costing (ABC) method was conducted to calculate total cost of included diagnostic techniques based on data provided by Dutch pathology laboratories and the Dutch-centralized cancer WGS facility. Costs were allocated to four categories: capital costs, maintenance costs, software costs, and operational costs. Results: The total cost per cancer patient per technique varied from € 58 (Sanger sequencing, three amplicons) to € 2925 (paired tumor-normal WGS). The operational costs accounted for the vast majority (over 90%) of the total per cancer patient technique costs. Conclusion: This study outlined in detail all costing aspects and cost prices of current and new diagnostic modalities used in treatment of NSCLC, melanoma, CRC, and GIST in the Netherlands. Detailed cost differences and value comparisons between these diagnostic techniques enable future economic evaluations to support decision-making
Promoter methylation of Wnt-antagonists in polypoid and nonpolypoid colorectal adenomas.
BACKGROUND: Nonpolypoid adenomas are a subgroup of colorectal adenomas that have been associated with a more aggressive clinical behaviour compared to their polypoid counterparts. A substantial proportion of nonpolypoid and polypoid adenomas lack APC mutations, APC methylation or chromosomal loss of the APC locus on chromosome 5q, suggesting the involvement of other Wnt-pathway genes. The present study investigated promoter methylation of several Wnt-pathway antagonists in both nonpolypoid and polypoid adenomas. METHODS: Quantitative methylation-specific PCR (qMSP) was used to evaluate methylation of four Wnt-antagonists, SFRP2, WIF-1, DKK3 and SOX17 in 18 normal colorectal mucosa samples, 9 colorectal cancer cell lines, 18 carcinomas, 44 nonpolypoid and 44 polypoid adenomas. Results were integrated with previously obtained data on APC mutation, methylation and chromosome 5q status from the same samples. RESULTS: Increased methylation of all genes was found in the majority of cell lines, adenomas and carcinomas compared to normal controls. WIF-1 and DKK3 showed a significantly lower level of methylation in nonpolypoid compared to polypoid adenomas (p < 0.01). Combining both adenoma types, a positive trend between APC mutation and both WIF-1 and DKK3 methylation was observed (p < 0.05). CONCLUSIONS: Methylation of Wnt-pathway antagonists represents an additional mechanism of constitutive Wnt-pathway activation in colorectal adenomas. Current results further substantiate the existence of partially alternative Wnt-pathway disruption mechanisms in nonpolypoid compared to polypoid adenomas, in line with previous observations
Promoter methylation of Wnt-antagonists in polypoid and nonpolypoid colorectal adenomas
BACKGROUND: Nonpolypoid adenomas are a subgroup of colorectal adenomas that have been associated with a more aggressive clinical behaviour compared to their polypoid counterparts. A substantial proportion of nonpolypoid and polypoid adenomas lack APC mutations, APC methylation or chromosomal loss of the APC locus on chromosome 5q, suggesting the involvement of other Wnt-pathway genes. The present study investigated promoter methylation of several Wnt-pathway antagonists in both nonpolypoid and polypoid adenomas. METHODS: Quantitative methylation-specific PCR (qMSP) was used to evaluate methylation of four Wnt-antagonists, SFRP2, WIF-1, DKK3 and SOX17 in 18 normal colorectal mucosa samples, 9 colorectal cancer cell lines, 18 carcinomas, 44 nonpolypoid and 44 polypoid adenomas. Results were integrated with previously obtained data on APC mutation, methylation and chromosome 5q status from the same samples. RESULTS: Increased methylation of all genes was found in the majority of cell lines, adenomas and carcinomas compared to normal controls. WIF-1 and DKK3 showed a significantly lower level of methylation in nonpolypoid compared to polypoid adenomas (p < 0.01). Combining both adenoma types, a positive trend between APC mutation and both WIF-1 and DKK3 methylation was observed (p < 0.05). CONCLUSIONS: Methylation of Wnt-pathway antagonists represents an additional mechanism of constitutive Wnt-pathway activation in colorectal adenomas. Current results further substantiate the existence of partially alternative Wnt-pathway disruption mechanisms in nonpolypoid compared to polypoid adenomas, in line with previous observations
VALHUDES: A protocol for validation of human papillomavirus assays and collection devices for HPV testing on self-samples and urine samples
<p><b>BACK GROUND: </b>Systematic reviews have concluded that hrHPV DNA testing using target-amplification tests is as accurate on vaginal self-samples as on clinician-taken specimens for the detection of cervical precancer. However, insufficient evidence is available for specific HPV assay/self-sample device combinations.</p>
<p><b>OBJECTIVES: </b>The VALHUDES protocol is designed as a diagnostic test accuracy study that aims to compare the clinical sensitivity and specificity of particular hrHPV assay(s) on vaginal self-samples and first-void-urine, collected in agreement with standardized protocols, with hrHPV testing on matched clinician-taken samples.</p>
<p><b>STUDY DESIGN: </b>Five hundred enrolled women referred to a colposcopy clinic are invited to collect a first-void urine sample and one or more vaginal self-samples with particular devices before collection of a cervical sample by a clinician. Sample sets are subsequently analysed in a laboratory accredited for HPV testing. Disease verification for all enrolled patients is provided by colposcopy combined with histological assessment of biopsies.</p>
<p><b>RESULTS: </b>A first VALHUDES study has started in Belgium in December 2017 with enrolment from four colposcopy centres. The following assays are foreseen to be evaluated: RealTime High Risk HPV assay (Abbott), cobas-4800 and -6800 (Roche), Onclarity (BD), Xpert HPV (Cepheid) and Anyplex II HPV HR (Seegene).</p>
<p><b>CONCLUSION: </b>Given empirical evidence that the relative accuracy of HPV-testing on self- vs clinician-samples is robust across clinical settings, the VALHUDES protocol offers a framework for validation of HPV assay/self-sample device combinations that can be translated to a primary screening setting.</p></p
Feasibility of whole-genome sequencing-based tumor diagnostics in routine pathology practice
The current increase in number and diversity of targeted anticancer agents poses challenges to the logistics and timeliness of molecular diagnostics (MolDx), resulting in underdiagnosis and treatment. Whole-genome sequencing (WGS) may provide a sustainable solution for addressing current as well as future diagnostic challenges. The present study therefore aimed to prospectively assess feasibility, validity, and value of WGS in routine clinical practice. WGS was conducted independently of, and in parallel with, standard of care (SOC) diagnostics on routinely obtained tumor samples from 1,200 consecutive patients with metastatic cancer. Results from both tests were compared and discussed in a dedicated tumor board. From 1,200 patients, 1,302 samples were obtained, of which 1,216 contained tumor cells. WGS was successful in 70% (854/1,216) of samples with a median turnaround time of 11 days. Low tumor purity (<20%) was the main reason for not completing WGS. WGS identified 99.2% and SOC MolDx 99.7% of the total of 896 biomarkers found in genomic regions covered by both tests. Actionable biomarkers were found in 603/848 patients (71%). Of the 936 associated therapy options identified by WGS, 343 were identified with SOC MolDx (36.6%). Biomarker-based therapy was started in 147 patients. WGS revealed 49 not previously identified pathogenic germline variants. Fresh-frozen, instead of formalin-fixed and paraffin-embedded, sample logistics were easily adopted as experienced by the professionals involved. WGS for patients with metastatic cancer is well feasible in routine clinical practice, successfully yielding comprehensive genomic profiling for the vast majority of patients