Paragangliomas are neuroendocrine tumours that are often highly vascularized and, in most cases, benign. The gold-standard treatment is surgical resection for various reasons; however, this can be... Show moreParagangliomas are neuroendocrine tumours that are often highly vascularized and, in most cases, benign. The gold-standard treatment is surgical resection for various reasons; however, this can be challenging because of close proximity to coronary arteries. Paucity of data has resulted in different (hybrid) treatment strategies with unknown long -term outcomes, especially with respect to coronary reintervention after stenting. Here, we report a unique patient with multiple cardiac paragangliomas adjacent to both coronary arteries who underwent complete surgical resection. Cardioplegic arrest is recommended to facilitate resection and, if needed, to perform concomitant coronary artery bypass grafting or reconstruction of cardiovascular structures. Show less
Terlouw, D.; Boot, A.; Ducarmon, Q.R.; Nooij, S.; Suerink, M.; Leerdam, M.E. van; ... ; Morreau, H. 2024
BackgroundColibactin, a genotoxin produced by polyketide synthase harboring (pks+) bacteria, induces double-strand breaks and chromosome aberrations. Consequently, enrichment of pks+Escherichia... Show moreBackgroundColibactin, a genotoxin produced by polyketide synthase harboring (pks+) bacteria, induces double-strand breaks and chromosome aberrations. Consequently, enrichment of pks+Escherichia coli in colorectal cancer and polyposis suggests a possible carcinogenic effect in the large intestine. Additionally, specific colibactin-associated mutational signatures; SBS88 and ID18 in the Catalogue of Somatic Mutations in Cancer database, are detected in colorectal carcinomas. Previous research showed that a recurrent APC splice variant perfectly fits SBS88.MethodsIn this study, we explore the presence of colibactin-associated signatures and fecal pks in an unexplained polyposis cohort. Somatic targeted Next-Generation Sequencing (NGS) was performed for 379 patients. Additionally, for a subset of 29 patients, metagenomics was performed on feces and mutational signature analyses using Whole-Genome Sequencing (WGS) on Formalin-Fixed Paraffin Embedded (FFPE) colorectal tissue blocks.ResultsNGS showed somatic APC variants fitting SBS88 or ID18 in at least one colorectal adenoma or carcinoma in 29% of patients. Fecal metagenomic analyses revealed enriched presence of pks genes in patients with somatic variants fitting colibactin-associated signatures compared to patients without variants fitting colibactin-associated signatures. Also, mutational signature analyses showed enrichment of SBS88 and ID18 in patients with variants fitting these signatures in NGS compared to patients without.ConclusionsThese findings further support colibactins ability to mutagenize colorectal mucosa and contribute to the development of colorectal adenomas and carcinomas explaining a relevant part of patients with unexplained polyposis. Show less
Pseudoinvasion (PI) is a benign lesion in which cancer is mimicked in the colon by misplacement of dysplastic glands in the submucosa. Although there are morphological clues, the discrimination of... Show morePseudoinvasion (PI) is a benign lesion in which cancer is mimicked in the colon by misplacement of dysplastic glands in the submucosa. Although there are morphological clues, the discrimination of PI from true invasion can be a challenge during pathological evaluation of colon adenomas. Both overdiagnosis and underdiagnosis can result in inadequate clinical decisions. This calls for novel tools to aid in cases where conventional methods do not suffice. We performed mass spectrometry imaging (MSI)-based spatial glycomics analysis on a cohort of formalin-fixed paraffin-embedded tissue (FFPE) material from 16 patients who underwent polypectomy. We used this spatial glycomic data to reconstruct the molecular histology of the tissue section using spatial segmentation based on uniform manifold approximation and projection for dimension reduction (UMAP). We first showed that the spatial glycomic phenotypes of the different morphological entities separated as distinct clusters in colon tissues, we separated true invasion from the other morphological entities. Then, we found that the glycomic phenotype in areas with suspected PI in the submucosa was strongly correlating with the corresponding glycomic phenotype of the adenomatous colon epithelium from the same tissue section (Pearson correlation distance average = 0.18). These findings suggest that using spatial glycomics, we can distinguish PI as having a molecular phenotype similar to the corresponding surface epithelium and true invasion as having a different phenotype even when compared to high-grade dysplasia. Therefore, when a novel molecular phenotype is found in the deepest submucosal region, this may be used as an argument in favor of true invasion. Show less
Polyketide synthase (pks) island harboring Escherichia coli are, under the right circumstances, able to produce the genotoxin colibactin. Colibactin is a risk factor for the development of... Show morePolyketide synthase (pks) island harboring Escherichia coli are, under the right circumstances, able to produce the genotoxin colibactin. Colibactin is a risk factor for the development of colorectal cancer and associated with mutational signatures SBS88 and ID18. This study explores colibactin-associated mutational signatures in biallelic NTHL1 and MUTYH patients. Targeted Next Generation Sequencing (NGS) was performed on colorectal adenomas and carcinomas of one biallelic NTHL and 12 biallelic MUTYH patients. Additional fecal metagenomics and genome sequencing followed by mutational signature analysis was conducted for the NTHL1 patient. Targeted NGS of the NTHL1 patient showed somatic APC variants fitting SBS88 which was confirmed using WGS. Furthermore, fecal metagenomics revealed pks genes. Also, in 1 out of 11 MUTYH patient a somatic variant was detected fitting SBS88. This report shows that colibactin may influence development of colorectal neoplasms in predisposed patients. Show less
Koster, E.J. de; Corver, W.E.; Geus-Oei, L.F. de; Oyen, W.J.G.; Ruano, D.; Schepers, A.; ... ; Morreau, H. 2023
Differentiated non-medullary thyroid cancer (NMTC) can be effectively treated by surgery followed by radioactive iodide therapy. However, a small subset of patients shows recurrence due to a loss... Show moreDifferentiated non-medullary thyroid cancer (NMTC) can be effectively treated by surgery followed by radioactive iodide therapy. However, a small subset of patients shows recurrence due to a loss of iodide transport, a phenotype frequently associated with BRAF V600E mutations. In theory, this should enable the use of existing targeted therapies specifically designed for BRAF V600E mutations. However, in practice, generic or specific drugs aimed at molecular targets identified by next generation sequencing (NGS) are not always beneficial. Detailed kinase profiling may provide additional information to help improve therapy success rates. In this study, we therefore investigated whether serine/threonine kinase (STK) activity profiling can accurately classify benign thyroid lesions and NMTC. We also determined whether dabrafenib (BRAF V600E-specific inhibitor), as well as sorafenib and regorafenib (RAF inhibitors), can differentiate BRAF V600E from non-BRAF V600E thyroid tumors. Using 21 benign and 34 malignant frozen thyroid tumor samples, we analyzed serine/threonine kinase activity using PamChip®peptide microarrays. An STK kinase activity classifier successfully differentiated malignant (26/34; 76%) from benign tumors (16/21; 76%). Of the kinases analyzed, PKC (theta) and PKD1 in particular, showed differential activity in benign and malignant tumors, while oncocytic neoplasia or Graves’ disease contributed to erroneous classifications. Ex vivo BRAF V600E-specific dabrafenib kinase inhibition identified 6/92 analyzed peptides, capable of differentiating BRAF V600E-mutant from non-BRAF V600E papillary thyroid cancers (PTCs), an effect not seen with the generic inhibitors sorafenib and regorafenib. In conclusion, STK activity profiling differentiates benign from malignant thyroid tumors and generates unbiased hypotheses regarding differentially active kinases. This approach can serve as a model to select novel kinase inhibitors based on tissue analysis of recurrent thyroid and other cancers. Show less
Werf-'t, A.S. van der; Terlouw, D.; Tops, C.M.; Kan, M.S. van; Hest, L.P. van; Gille, H.J.P.; ... ; Nielsen, M. 2023
Diagnosis of Lynch syndrome (LS) caused by a pathogenic germline MSH6 variant may be complicated by discordant immunohistochemistry (IHC) and/or by a microsatellite stable (MSS) phenotype. This... Show moreDiagnosis of Lynch syndrome (LS) caused by a pathogenic germline MSH6 variant may be complicated by discordant immunohistochemistry (IHC) and/or by a microsatellite stable (MSS) phenotype. This study aimed to identify the various causes of the discordant phenotypes of colorectal cancer (CRC) and endometrial cancer (EC) in MSH6-associated LS. Data were collected from Dutch family cancer clinics. Carriers of a (likely) pathogenic MSH6 variant diagnosed with CRC or EC were categorized based on an microsatellite instability (MSI)/IHC test outcome that might fail to result in a diagnosis of LS (eg, retained staining of all 4 mismatch repair proteins, with or without an MSS phenotype, and other staining patterns). When tumor tissue was available, MSI and/or IHC were repeated. Next-generation sequencing (NGS) was performed in cases with discordant staining patterns. Data were obtained from 360 families with 1763 (obligate) carriers. MSH6 variant carriers with CRC or EC (n = 590) were included, consisting of 418 CRCs and 232 ECs. Discordant staining was reported in 77 cases (36% of MSI/IHC results). Twelve patients gave informed consent for further analysis of tumor material. Upon revision, 2 out of 3 MSI/IHC cases were found to be concordant with the MSH6 variant, and NGS showed that 4 discordant IHC results were sporadic rather than LS-associated tumors. In 1 case, somatic events explained the discordant phenotype. The use of reflex IHC mismatch repair testing, the current standard in most Western countries, may lead to the misdiagnosis of germline MSH6 variant carriers. The pathologist should point out that further diagnostics for inheritable colon cancer, including LS, should be considered in case of a strong positive family history. Germline DNA analysis of the mismatch repair genes, preferably as part of a larger gene panel, should therefore be considered in potential LS patients. Show less
Hoes, L.R.; Henegouwen, J.M.V.; Wijngaart, H. van der; Zeverijn, L.J.; Velden, D.L. van der; Haar, J. van de; ... ; Voest, E.E. 2023
BACKGROUND & AIMS: Recent pancreatic cancer surveil-lance programs of high-risk individuals have reported improved outcomes. This study assessed to what extent outcomes of pancreatic ductal... Show moreBACKGROUND & AIMS: Recent pancreatic cancer surveil-lance programs of high-risk individuals have reported improved outcomes. This study assessed to what extent outcomes of pancreatic ductal adenocarcinoma (PDAC) patients with a CDKN2A/p16 pathogenic variant diagnosed under surveillance are better as compared with patients with PDAC diagnosed outside surveillance.METHODS: In a pro-pensity score matched cohort using data from the Netherlands Cancer Registry, we compared resectability, stage, and survival between patients diagnosed under sur-veillance with non-surveillance patients with PDAC. Survival analyses were adjusted for potential effects of lead time.RESULTS: Between January 2000 and December 2020, 43,762 patients with PDAC were identified from the Netherlands Cancer Registry. Thirty-one patients with PDAC under surveillance were matched in a 1:5 ratio with 155 non surveillance patients based on age at diagnosis, sex, year diagnosis, and tumor location. Outside surveillance, 5.8% of the patients had stage I cancer, as compared with 38.7% of surveillance patients with PDAC (odds ratio [OR], 0.09; 95% confidence interval [CI], 0.04-0.19). In total, 18.7% of non surveillance patients vs 71.0% of surveillance patients un- derwent a surgical resection (OR, 10.62; 95% CI, 4.56-26.63). Patients in surveillance had a better prognosis, reflected by 5-year survival of 32.4% and a median overall survival of 26.8 months vs 4.3% 5-year survival and 5.2 months median overall survival in non-surveillance patients (hazard ratio, 0.31; 95% CI 0.19-0.50). For all adjusted lead times, survival remained significantly longer in surveillance patients than non-surveillance patients.CONCLUSION: Surveillance for PDAC in carriers of a CDKN2A/p16 pathogenic variant results in earlier detection, increased resectability, and improved survival as compared with non-surveillance patients with PDAC. Show less
Ibrahim, I.S.; Vasen, H.F.A.; Wasser, M.N.J.M.; Feshtali, S.; Bonsing, B.A.; Morreau, H.; ... ; Hout, W.B. van den 2023
Background: CDKN2A-p16-Leiden mutation carriers have a high lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC), with very poor survival. Surveillance may improve prognosis.... Show moreBackground: CDKN2A-p16-Leiden mutation carriers have a high lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC), with very poor survival. Surveillance may improve prognosis. Objective: To assess the cost-effectiveness of surveillance, as compared to no surveillance. Methods: In 2000, a surveillance program was initiated at Leiden University Medical Center with annual MRI and optional endoscopic ultrasound. Data were collected on the resection rate of screen-detected tumors and on survival. The Kaplan-Meier method and a parametric cure model were used to analyze and compare survival. Based on the surveillance and survival data from the screening program, a state-transition model was constructed to estimate lifelong outcomes. Results: A total of 347 mutation carriers participated in the surveillance program. PDAC was detected in 31 patients (8.9%) and the tumor could be resected in 22 patients (71.0%). Long-term cure among patients with resected PDAC was estimated at 47.1% (p < 0.001). The surveillance program was estimated to reduce mortality from PDAC by 12.1% and increase average life expectancy by 2.10 years. Lifelong costs increased by euro13,900 per patient, with a cost-utility ratio of euro14,000 per quality-adjusted life year gained. For annual surveillance to have an acceptable cost-effectiveness in other settings, lifetime PDAC risk needs to be 10% or higher. Conclusion: The tumor could be resected in most patients with a screen-detected PDAC. These patients had considerably better survival and as a result annual surveillance was found to be cost-effective. Show less
Ibrahim, I.S.; Vasen, H.F.A.; Wasser, M.N.J.M.; Feshtali, S.; Bonsing, B.A.; Morreau, H.; ... ; Hout, W.B. van den 2023
BackgroundCDKN2A-p16-Leiden mutation carriers have a high lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC), with very poor survival. Surveillance may improve prognosis... Show moreBackgroundCDKN2A-p16-Leiden mutation carriers have a high lifetime risk of developing pancreatic ductal adenocarcinoma (PDAC), with very poor survival. Surveillance may improve prognosis.ObjectiveTo assess the cost-effectiveness of surveillance, as compared to no surveillance.MethodsIn 2000, a surveillance program was initiated at Leiden University Medical Center with annual MRI and optional endoscopic ultrasound. Data were collected on the resection rate of screen-detected tumors and on survival. The Kaplan–Meier method and a parametric cure model were used to analyze and compare survival. Based on the surveillance and survival data from the screening program, a state-transition model was constructed to estimate lifelong outcomes.ResultsA total of 347 mutation carriers participated in the surveillance program. PDAC was detected in 31 patients (8.9%) and the tumor could be resected in 22 patients (71.0%). Long-term cure among patients with resected PDAC was estimated at 47.1% (p < 0.001). The surveillance program was estimated to reduce mortality from PDAC by 12.1% and increase average life expectancy by 2.10 years. Lifelong costs increased by €13,900 per patient, with a cost-utility ratio of €14,000 per quality-adjusted life year gained. For annual surveillance to have an acceptable cost-effectiveness in other settings, lifetime PDAC risk needs to be 10% or higher.ConclusionThe tumor could be resected in most patients with a screen-detected PDAC. These patients had considerably better survival and as a result annual surveillance was found to be cost-effective. Show less
Roelands, J.; Ploeg, M. van der; Ijsselsteijn, M.E.; Dang, H.; Boonstra, J.J.; Hardwick, J.C.H.; ... ; Miranda, N.F.C.C. de 2022
ObjectiveBiological insights into the stepwise development and progression of colorectal cancer (CRC) are imperative to develop tailored approaches for early detection and optimal clinical... Show moreObjectiveBiological insights into the stepwise development and progression of colorectal cancer (CRC) are imperative to develop tailored approaches for early detection and optimal clinical management of this disease. Here, we aimed to dissect the transcriptional and immunologic alterations that accompany malignant transformation in CRC and to identify clinically relevant biomarkers through spatial profiling of pT1 CRC samples. DesignWe employed digital spatial profiling (GeoMx) on eight pT1 CRCs to study gene expression in the epithelial and stromal segments across regions of distinct histology, including normal mucosa, low-grade and high-grade dysplasia and cancer. Consecutive histology sections were profiled by imaging mass cytometry to reveal immune contextures. Finally, publicly available single-cell RNA-sequencing data was analysed to determine the cellular origin of relevant transcripts. ResultsComparison of gene expression between regions within pT1 CRC samples identified differentially expressed genes in the epithelium (n=1394 genes) and the stromal segments (n=1145 genes) across distinct histologies. Pathway analysis identified an early onset of inflammatory responses during malignant transformation, typified by upregulation of gene signatures such as innate immune sensing. We detected increased infiltration of myeloid cells and a shift in macrophage populations from pro-inflammatory HLA-DR(+)CD204(-) macrophages to HLA-DR(-)CD204(+) immune-suppressive subsets from normal tissue through dysplasia to cancer, accompanied by the upregulation of the CD47/SIRP alpha 'don't eat me signal'. ConclusionSpatial profiling revealed the molecular and immunological landscape of CRC tumourigenesis at early disease stage. We identified biomarkers with strong association with disease progression as well as targetable immune processes that are exploitable in a clinical setting. Show less
Terlouw, D.; Hes, F.J.; Suerink, M.; Boot, A.; Langers, A.M.J.; Tops, C.M.; ... ; Nielsen, M. 2022
PURPOSE: Pancreatic cancer surveillance in high-risk individuals may lead to detection of pancreatic ductal adenocarcinoma (PDAC) at an earlier stage and with improved survival. This study... Show morePURPOSE: Pancreatic cancer surveillance in high-risk individuals may lead to detection of pancreatic ductal adenocarcinoma (PDAC) at an earlier stage and with improved survival. This study evaluated the yield and outcomes of 20 years of prospective surveillance in a large cohort of individuals with germline pathogenic variants (PVs) in CDKN2A. METHODS: Prospectively collected data were analyzed from individuals participating in pancreatic cancer surveillance. Surveillance consisted of annual magnetic resonance imaging with magnetic resonance cholangiopancreatography and optional endoscopic ultrasound. RESULTS: Three hundred forty-seven germline PV carriers participated in surveillance and were followed for a median of 5.6 (interquartile range 2.3-9.9) years. A total of 36 cases of PDAC were diagnosed in 31 (8.9%) patients at a median age of 60.4 (interquartile range 51.3-64.1) years. The cumulative incidence of primary PDAC was 20.7% by age 70 years. Five carriers (5 of 31; 16.1%) were diagnosed with a second primary PDAC. Thirty (83.3%) of 36 PDACs were considered resectable at the time of imaging. Twelve cases (12 of 36; 33.3%) presented with stage I disease. The median survival after diagnosis of primary PDAC was 26.8 months, and the 5-year survival rate was 32.4% (95% CI, 19.1 to 54.8). Individuals with primary PDAC who underwent resection (22 of 31; 71.0%) had an overall 5-year survival rate of 44.1% (95% CI, 27.2 to 71.3). Nine (2.6%; 9 of 347) individuals underwent surgery for a suspected malignant lesion, which proved to not be PDAC, and this included five lesions with low-grade dysplasia. CONCLUSION: This long-term surveillance study demonstrates a high incidence of PDAC in carriers of a PV in CDKN2A. This provides evidence that surveillance in such a high-risk population leads to detection of early-stage PDAC with improved resectability and survival. Show less
PURPOSEPancreatic cancer surveillance in high-risk individuals may lead to detection of pancreatic ductal adenocarcinoma (PDAC) at an earlier stage and with improved survival. This study evaluated... Show morePURPOSEPancreatic cancer surveillance in high-risk individuals may lead to detection of pancreatic ductal adenocarcinoma (PDAC) at an earlier stage and with improved survival. This study evaluated the yield and outcomes of 20 years of prospective surveillance in a large cohort of individuals with germline pathogenic variants (PVs) in CDKN2A.METHODSProspectively collected data were analyzed from individuals participating in pancreatic cancer surveillance. Surveillance consisted of annual magnetic resonance imaging with magnetic resonance cholangiopancreatography and optional endoscopic ultrasound.RESULTSThree hundred forty-seven germline PV carriers participated in surveillance and were followed for a median of 5.6 (interquartile range 2.3-9.9) years. A total of 36 cases of PDAC were diagnosed in 31 (8.9%) patients at a median age of 60.4 (interquartile range 51.3-64.1) years. The cumulative incidence of primary PDAC was 20.7% by age 70 years. Five carriers (5 of 31; 16.1%) were diagnosed with a second primary PDAC. Thirty (83.3%) of 36 PDACs were considered resectable at the time of imaging. Twelve cases (12 of 36; 33.3%) presented with stage I disease. The median survival after diagnosis of primary PDAC was 26.8 months, and the 5-year survival rate was 32.4% (95% CI, 19.1 to 54.8). Individuals with primary PDAC who underwent resection (22 of 31; 71.0%) had an overall 5-year survival rate of 44.1% (95% CI, 27.2 to 71.3). Nine (2.6%; 9 of 347) individuals underwent surgery for a suspected malignant lesion, which proved to not be PDAC, and this included five lesions with low-grade dysplasia.CONCLUSIONThis long-term surveillance study demonstrates a high incidence of PDAC in carriers of a PV in CDKN2A. This provides evidence that surveillance in such a high-risk population leads to detection of early-stage PDAC with improved resectability and survival. Show less
Aiyer, K.T.S.; Doeleman, T.; Ryan, N.A.; Nielsen, M.; Crosbie, E.J.; Smit, V.T.H.B.M.; ... ; Bosse, T. 2022
Reflex mismatch repair immunohistochemistry (MMR IHC) testing for MLH1, PMS2, MSH2 and MSH6 is used to screen for Lynch syndrome. Recently MMR-deficiency (MMRd) has been approved as a pan-cancer... Show moreReflex mismatch repair immunohistochemistry (MMR IHC) testing for MLH1, PMS2, MSH2 and MSH6 is used to screen for Lynch syndrome. Recently MMR-deficiency (MMRd) has been approved as a pan-cancer predictive biomarker for checkpoint inhibitor therapy, leading to a vast increase in the use of MMR IHC in clinical practice. We explored whether immunohistochemical staining with PMS2 and MSH6 can be used as a reliable substitute. This two-antibody testing algorithm has the benefit of saving tissue, cutting costs and saving time. PubMed, Embase and Cochrane library were systematically searched for articles reporting on MMR IHC. The weighed percentage of cases with isolated MLH1 or MSH2 loss or combined MLH1/MSH2 loss alone was analyzed using a random effects model meta-analysis in R. The search yielded 1704 unique citations, of which 131 studies were included, describing 9014 patients. A weighed percentage of 1.1% (95% CI 0.53-18.87, I = 87%) of cases with isolated MLH1 or MSH2 loss or combined MLH1/MSH2 loss alone was observed. In the six articles with the main aim of investigating the two-antibody testing algorithm all MMRd cases were detected with the two-antibody testing algorithm, there were no cases with isolated MLH1 or MSH2 loss or combined MLH1/MSH2 loss alone. This high detection rate of MMRd of the two-antibody testing algorithm supports its use in clinical practice by specialized pathologists. Staining of all four antibodies should remain the standard in cases with equivocal results of the two-antibody testing algorithm. Finally, educational sessions in which staining pattern pitfalls are discussed will continue to be important. Show less
Hondelink, L.M.; Schrader, A.M.R.; Aghmuni, G.A.; Solleveld-Westerink, N.; Cleton-Jansen, A.M.; Egmond, D. van; ... ; Cohen, D. 2022
Introduction: Since the approval of neurotrophic tropomyosin receptor kinase (NTRK) tyrosine kinase inhibitors for fist-line advanced stage pan-cancer therapy, pathologists and molecular biologists... Show moreIntroduction: Since the approval of neurotrophic tropomyosin receptor kinase (NTRK) tyrosine kinase inhibitors for fist-line advanced stage pan-cancer therapy, pathologists and molecular biologists have been facing a complex question: how should the large volume of specimens be screened for NTRK fusions? Immunohistochemistry is fast and cheap, but the sensitivity compared to RNA NGS is unclear.Methods: We performed RNA-based next-generation sequencing on 1,329 cases and stained 24 NTRK-rearranged cases immunohistochemically with pan-TRK (ERP17341). Additionally, we performed a meta-analysis of the literature. After screening 580 studies, 200 additional NTRK-rearranged cases from 13 studies, analysed with sensitive molecular diagnostics as well as pan-TRK IHC, were included.Results: In the included 224 NTRK-rearranged solid tumours, the sensitivity for pan-TRK IHC was 82% and the false-negative rate was 18%. NTRK3 fusions had more false negatives (27%) compared to NTRK1 (6%) and NTRK2 (14%) (p = 0.0006). Membranous, nuclear and peri-nuclear staining patterns strongly correlated with different fusion products, with membranous staining being more prevalent in NTRK1 and NTRK2, nuclear in NTRK3, and perinuclear in NTRK1.Conclusion: Despite a reduction in the number of molecular analysis, using pan-TRK immunohistochemistry as a prescreening method to detect NTRK fusions in solid tumours will miss 18% of all NTRK-fused cases (especially involving NTRK3). Therefore, the most comprehensive and optimal option to detect NTRK fusions is to perform molecular testing on all eligible cases. However, in case of financial or logistical limitations, an immunohistochemistry-first approach is defensible in tumours with a low prevalence of NTRK fusions. (C) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Show less
Brouwer, T.; Ijsselsteijn, M.; Oosting, J.; Ruano, D.; Ploeg, M. van der; Dijk, F.; ... ; Miranda, N. de 2022
Simple Summary: Pancreatic cancer is one of the most lethal cancer types and its high refractoriness to therapies, including immunotherapy, has often been associated with the predominantly immune... Show moreSimple Summary: Pancreatic cancer is one of the most lethal cancer types and its high refractoriness to therapies, including immunotherapy, has often been associated with the predominantly immune suppressive tumor microenvironment that characterizes pancreatic tumors. Regulatory T cells (Tregs) are generally considered as drivers of immune suppression in cancers. However, an increasing number of reports suggest a paradoxical association between tumor infiltration by Tregs and improved patient prognosis, in particular in gastrointestinal cancers. Here we show that Treg infiltration in pancreatic ductal adenocarcinomas (PDAC) is associated with better overall survival of patients. Abstract: Pancreatic ductal adenocarcinoma (PDAC) is considered to be a poorly immunogenic cancer type that combines a low mutation burden with a strong immunosuppressive tumor microenvironment. Regulatory T cells (Tregs) are major drivers of immune suppression but their prognostic role, particularly in gastrointestinal malignancies, remains controversial. Lymphocytic infiltration in 122 PDAC samples was assessed by multispectral immunofluorescence with anti-Keratin, -CD3, -CD8, -FOXP3 and -CD163 antibodies. Differential infiltration by Tregs was analyzed in the context of transcriptomic profiles that were available for 65 tumors. High infiltration of CD3(+)CD8(-) (mainly CD4(+)) T cells and, especially, of the subset expressing FOXP3 (Tregs) was associated with improved patient survival, whilst cytotoxic CD3(+)CD8(+) T cell infiltration did not have an impact on overall survival. Transcriptomic analysis revealed three signatures in PDAC tumors comprising of epithelial-mesenchymal transition (EMT)/stromal, metabolic, and secretory/pancreatic signature. However, none of these signatures explained differences in Treg infiltration. We show that Tregs associate with improved overall survival in PDAC patients. This effect was independent of cytotoxic T cell infiltration and the transcriptomic profiles of their respective tumors. These findings provide a new layer of complexity in the study of PDAC tumor microenvironment that must be considered when developing immunotherapeutic interventions for this disease. Show less
Helderman, N.C.; Elsayed, F.A.; Wezel, T. van; Terlouw, D.; Langers, A.M.J.; Egmond, D. van; ... ; Suerink, M. 2022
& nbsp;Small intestine-neuroendocrine tumors (SI-NETs) are one of the most common tumors of the small bowel. Despite an increasing incidence, the exact mechanisms driving underlying pathology... Show more& nbsp;Small intestine-neuroendocrine tumors (SI-NETs) are one of the most common tumors of the small bowel. Despite an increasing incidence, the exact mechanisms driving underlying pathology remain to be determined. Interestingly, recent studies linked the development of (SI-)NETs to both Lynch syndrome (LS) and MUTYH variants. If confirmed, these associations would have important consequences for treatment. In this study we therefore investigated the prevalence of mismatch repair (MMR) deficiency and MUTYH variants in 64 primary resected SI-NETs. Immunohistochemistry was used to assess the expression of the MMR genes, and competitive allele-specific PCR (KASPar) targeting two hotspot MUTYH variants [p.(Tyr179Cys), p.(Gly396Asp)] was performed to determine their prevalence in SI-NETs. Strikingly, all 64 SI-NETs stained positive for MSH6 and PMS2, indicating & nbsp;MMR proficiency. In addition, no MUTYH hotspot variant was found in any of the 64 SI-NETs. As such, these results do not support an association between SI-NET development and LS or MUTYH variants. In order to gain insight into SI-NET pathogenesis and optimally manage patients, future research should therefore focus on other candidate genes. (C) 2022 Published by Elsevier Inc Show less
