European follow-up of incorrect biomarker results for colorectal cancer demonstrates the importance of quality improvement projects.

Biomarker analysis for colorectal cancer has been shown to be reliable in Europe with 97% of samples tested by EQA participants to be correctly classified. This study focuses on errors during the annual EQA assessment. The aim was to explore the causes and actions related to the observed errors and to provide feedback and assess any improvement between 2016 and 2017. An electronic survey was sent to all laboratories with minimum one genotyping error or technical failure on ten tumor samples. A workshop was organized based on 2016 survey responses. Improvement of performance in 2017 was assessed for returning participants (n = 76), survey respondents (n = 13) and workshop participants (n = 4). Survey respondents and workshop participants improved in terms of (maximum) analysis score, successful participation, and genotyping errors compared to all returning participants. In 2016, mostly pre- and post-analytical errors (both 25%) were observed caused by unsuitability of the tumor tissue for molecular analysis. In 2017, most errors were due to analytical problems (50.0%) caused by methodological problems. The most common actions taken (n = 58) were protocol revisions (34.5%) and staff training (15.5%). In 24.1% of issues identified no action was performed. Corrective actions were linked to an improved performance, especially if performed by the pathologist. Although biomarker testing has improved over time, error occurrence at different phases stresses the need for quality improvement throughout the test process. Participation to quality improvement projects and a close collaboration with the pathologist can have a positive influence on performance.

Rare cancers in The Netherlands: a population-based study.

The conventional definition for rare disease is based on prevalence. Because of differences in prognosis, a definition on the basis of incidence was deemed to be more appropriate for rare cancers. Within the European RARECARE project, a definition was introduced that defines cancers as rare when the crude incidence rate is less than six per 100 000 per year. In this study, we applied the RARECARE definition for rare cancer to the Netherlands; this to identify the usefulness of the definition in a single country and to provide more insight into the burden of rare cancers in the Netherlands. Data for 2004 through 2008 were extracted from the Netherlands Cancer Registry and classified according to the RARECARE entities (tumour groupings). Crude and European standardized incidence rates were calculated. Out of the 260 entities, 223 (86%) were rare according to the definition, accounting for 14 000 cancers (17% of all). Considerable fluctuations in crude rates over years were observed for the major group of cancers. Rare tumours in the Netherlands constituted 17% of all newly diagnosed tumours, but were divided over 223 different entities, indicating the challenge that faces clinicians. To make the definition of rare cancers better applicable, it should be refined by taking into consideration the sex-specific incidence for sex-specific cancer sites. Moreover, a mean incidence over 5 years will provide more solid insight into the burden, eliminating large fluctuations in time of most of the cancers.

The ins and outs of molecular pathology reporting.

The raid evolution in molecular pathology resulting in an increasing complexity requires careful reporting. The need for standardisation is clearer than ever. While synoptic reporting was first used for reporting hereditary genetic diseases, it is becoming more frequent in pathology, especially molecular pathology reports too. The narrative approach is no longer feasible with the growing amount of essential data present on the report, although narrative components are still necessary for interpretation in molecular pathology. On the way towards standardisation of reports, guidelines can be a helpful tool. There are several guidelines that focus on reporting in the field of hereditary diseases, but it is not always feasible to extrapolate these to the reporting of somatic variants in molecular pathology. The rise of multi-gene testing causes challenges for the laboratories. In order to provide a continuous optimisation of the laboratory testing process, including reporting, external quality assessment is essential and has already proven to improve the quality of reports. In general, a clear and concise report for molecular pathology can be created by including elements deemed important by different guidelines, adapting the report to the process flows of the laboratory and integrating the report with the laboratory information management system and the patient record.

Clinical features of patients with nodal marginal zone lymphoma compared to follicular lymphoma: similar presentation, but differences in prognostic factors and rate of transformation.

Nodal marginal zone lymphoma (NMZL) is a rare type of B-cell non-Hodgkin lymphoma. This study assessed the clinical features of 56 patients with NMZL in comparison to 46 patients with follicular lymphoma (FL). Patients with NMZL and FL had a largely similar clinical presentation, but patients with FL had a higher disease stage at presentation, more frequent abdominal lymphadenopathy and bone marrow involvement, and showed more common transformation into diffuse large B-cell lymphoma (DLBCL) during the course of disease. Overall survival and event-free survival were similar for patients with NMZL and FL, but factors associated with worse prognosis differed between the two groups. Transformation into DLBCL was associated with a significantly poorer outcome in both groups, but the phenotypes were different: DLBCL arising in FL was mainly of germinal center B-cell phenotype, whereas DLBCL arising in NMZL was mainly of non-germinal center B-cell phenotype.

Next generation sequencing in synovial sarcoma reveals novel gene mutations.

Over 95% of all synovial sarcomas (SS) share a unique translocation, t(X;18), however, they show heterogeneous clinical behavior. We analyzed multiple SS to reveal additional genetic alterations besides the translocation. Twenty-six SS from 22 patients were sequenced for 409 cancer-related genes using the Comprehensive Cancer Panel (Life Technologies, USA) on an Ion Torrent platform. The detected variants were verified by Sanger sequencing and compared to matched normal DNAs. Copy number variation was assessed in six tumors using the Oncoscan array (Affymetrix, USA). In total, eight somatic mutations were detected in eight samples. These mutations have not been reported previously in SS. Two of these, in KRAS and CCND1, represent known oncogenic mutations in other malignancies. Additional mutations were detected in RNF213, SEPT9, KDR, CSMD3, MLH1 and ERBB4. DNA alterations occurred more often in adult tumors. A distinctive loss of 6q was found in a metastatic lesion progressing under pazopanib, but not in the responding lesion. Our results emphasize t(X;18) as a single initiating event in SS and as the main oncogenic driver. Our results also show the occurrence of additional genetic events, mutations or chromosomal aberrations, occurring more frequently in SS with an onset in adults.

Next generation diagnostic molecular pathology: critical appraisal of quality assurance in Europe.

Tumor evaluation in pathology is more and more based on a combination of traditional histopathology and molecular analysis. Due to the rapid development of new cancer treatments that specifically target aberrant proteins present in tumor cells, treatment decisions are increasingly based on the molecular features of the tumor. Not only the number of patients eligible for targeted precision medicine, but also the number of molecular targets per patient and tumor type is rising. Diagnostic molecular pathology, the discipline that determines the molecular aberrations present in tumors for diagnostic, prognostic or predictive purposes, is faced with true challenges. The laboratories have to meet the need of comprehensive molecular testing using only limited amount of tumor tissue, mostly fixed in formalin and embedded in paraffin (FFPE), in short turnaround time. Choices must be made for analytical methods that provide accurate, reliable and cost-effective results. Validation of the test procedures and results is essential. In addition, participation and good performance in internal (IQA) and external quality assurance (EQA) schemes is mandatory. In this review, we critically evaluate the validation procedure for comprehensive molecular tests as well as the organization of quality assurance and assessment of competence of diagnostic molecular pathology laboratories within Europe.

[Tumour examination to detect hereditary colorectal cancer]. / Erfelijke darmkanker opsporen door tumoronderzoek.

Lynch syndrome is the most common cause of hereditary intestinal cancer, with a 30-70% risk of colorectal cancer (CRC). Prevention of CRC by colonoscopy in family members with Lynch syndrome is highly effective; therefore, it is important to trace as many people with this syndrome as possible. Criteria have been developed in the Netherlands to increase detection of hereditary colorectal cancer in a practically feasible and cost-effective way. Based on these criteria, the pathologist can perform microsatellite instability testing in patients recently diagnosed with CRC. The criteria are: CRC under the age of 50, second CRC under the age of 70, or CRC under the age of 70 with a concurrent or previous malignancy associated with Lynch syndrome. For family members and patients diagnosed with CRC more than a year ago, a digital test can be used to determine whether genetic counselling by a geneticist is indicated (www.umcn.nl/verwijzers).

Rapid-growing tumor of the cheek mimicking a malignant tumor: lipoblastoma of infancy.

In this case report, we describe a 5-month-old girl with a rapid-growing mass of the lower lip extending to the buccal cheek. After surgical interference, the diagnosis lipoblastoma was made. Dealing with a fast-growing tumor in an infant, lipoblastic tumors belong in the differential diagnosis, however, a malignant process cannot be excluded. Rapid-growing lipoblastoma of infancy is a very rare benign tumor of embryonic white fatty cells. Magnetic resonance imaging might help with the diagnosis and often shows a lesion composed mostly, but not entirely, of fat. In this case report, we want to draw attention to the problems with diagnosis and therapeutic management of children with lipoblastoma.

Double-staining chromogenic in situ hybridization as a useful alternative to split-signal fluorescence in situ hybridization in lymphoma diagnostics.

BACKGROUND: Malignant lymphomas are classified based on morphology, immunophenotype, genetics and clinical features. The pathological diagnosis is generally considered difficult and prone to mistakes. Since non-random chromosomal translocations are specifically involved in specific entities, their detection is an important adjunct for increasing the reliability of the diagnosis. Recently, split-signal fluorescence in situ hybridization has become available as a robust method to detect chromosomal breaks in paraffin-embedded formalin-fixed tissues. A bright field approach would bring this technology within the reach of every pathology laboratory. DESIGN AND METHODS: Our study was initiated to determine the consistency between chromogenic in situ hybridization and fluorescence in situ hybridization, both using split-signal probes developed for the detection of chromosomal breaks. Five hundred and forty cases of 11 lymphoma entities and reactive, benign lymphoid tissues, collected from eight different pathology laboratories, placed on 15 fluorescence in situ hybridization pre-stained tissue microarray slides, were double stained for the chromogenic hybridization. For each core morphology and actual signal were compared to the original fluorescence hybridization results. In addition, hematoxylin background staining intensity and signal intensity of the double-staining chromogenic in situ hybridization procedure were analyzed. RESULTS: With respect to the presence or absence of chromosomal breaks, 97% concordance was found between the results of the two techniques. Hematoxylin background staining intensity and signal intensity were found to correspond. The overall morphology after double-staining chromogenic in situ hybridization had decreased compared to the initial morphology scored after split-signal fluorescence in situ hybridization staining. CONCLUSIONS: We conclude that double-staining chromogenic in situ hybridization is equally reliable as fluorescence in situ hybridization in detecting chromosomal breaks in lymphoid tissue. Although differences in morphology, hematoxylin staining and chromogenic signal intensity vary between the tumor entities none of the entities appeared more easy or difficult to score.

Are there geographical differences in the frequency of SYT-SSX1 and SYT-SSX2 chimeric transcripts in synovial sarcoma?

Synovial sarcoma (SS) is characterized by the t(X;18)(p11.2;q11.2) chromosomal translocation, which results in generating either SYT-SSX1, SYT-SSX2 or, infrequently, SYT-SSX4 fusion gene. The ratio of SYT-SSX1:SYT-SSX2 fusions is close to 2:1 in the majority of studies, and SYT-SSX2 fusion has been only rarely observed in biphasic SS. In the present study, we compared two series of patients with SS, Slovenian (37 cases) and Dutch (14 cases), with respect to clinical, pathological and molecular findings. The two groups did not differ with regard to clinicopathological features. Whereas the frequency of different SYT-SSX fusions in the Dutch group was similar to that reported in the literature, we found an unexpectedly high number of tumors with SYT-SSX2 fusion in the Slovenian group. The ratio of SYT-SSX1:SYT-SSX2 fusion was 7:18 for monophasic and 2:7 for biphasic tumors in the Slovenian group. This distribution differs significantly from that observed in the Dutch group in the present study (P = 0.041) as well as from data reported in the recent large multi-institutional study on 243 patients (P = 0.0001). Our findings indicate possible geographical differences in the frequency of two SYT-SSX fusion transcripts in patients with synovial sarcoma.