A study in a Polish ataxia cohort indicates genetic heterogeneity and points to MTCL1 as a novel candidate gene.

Inherited ataxias are a group of highly heterogeneous, complex neurological disorders representing a significant diagnostic challenge in clinical practice. We performed a next-generation sequencing (NGS) analysis in 10 index cases with unexplained progressive cerebellar ataxia of suspected autosomal recessive inheritance. A definite molecular diagnosis was obtained in 5/10 families and included the following diseases: autosomal recessive spastic ataxia of Charlevoix-Saguenay, POLR3B-related hypomyelinating leukodystrophy, primary coenzyme Q10 deficiency type 4, Niemann-Pick disease type C1 and SYNE1-related ataxia. In addition, we found a novel homozygous MTCL1 loss of function variant p.(Lys407fs) in a 23-year-old patient with slowly progressive cerebellar ataxia, mild intellectual disability, seizures in childhood and episodic pain in the lower limbs. The identified variant is predicted to truncate the protein after first 444 of 1586 amino acids. MTCL1 encodes a microtubule-associated protein highly expressed in cerebellar Purkinje cells; its knockout in a mouse model causes ataxia. We propose MTCL1 as a candidate gene for autosomal recessive cerebellar ataxia in humans. In addition, our study confirms the high diagnostic yield of NGS in early-onset cerebellar ataxias, with at least 50% detection rate in our ataxia cohort.

Coincidence of PTPN22 c.1858CC and FCRL3 -169CC genotypes as a biomarker of preserved residual ß-cell function in children with type 1 diabetes.

BACKGROUND: Genotype-phenotype studies in type 1 diabetes (T1DM) patients are needed for further development of therapy strategies. OBJECTIVE: Our aims were to investigate the distribution of selected PTPN22 and FCRL3 gene polymorphisms and their associations with clinical course of disease in children with newly diagnosed T1DM from the Pomeranian region of Poland. SUBJECTS/METHODS: The prospective, longitudinal study of 147 children with newly diagnosed T1DM-autoimmune subtype was conducted. The PTPN22 c.1858T>C (rs2476601) and FCRL3 -169C>T (rs7528684) polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP) and DNA sequencing. The frequencies of genotypes were compared between the study and population-matched control group (327 random anonymous samples from the Pomeranian region). Selected patients underwent a 24-monthly follow up [periodic re-evaluation of fasting C-peptide concentration (FCP) and hemoglobin A1c (HbA1c ) level]. RESULTS: A significantly lower coincidence of the PTPN22 c.1858CC and FCRL3 -169CC genotypes was found in the study group compared with controls (P = 0.04). The PTPN22 c.1858CC and FCRL3 -169CC genotype combination, restricted to female patients only, was associated with well-preserved residual ß-cell function throughout the entire follow up (prolonged FCP level increase up to the sixth month of disease, with further very stable dynamics-FCP median level ≥0.67 ng/mL without significant decrease up to the 24th month). HbA1c levels in this subgroup also remained the lowest during the observation period. CONCLUSIONS/INTERPRETATION: Ascertained phenomenon could be explained by an interacting mechanism of the two polymorphisms through estrogen-regulated nuclear factor kappa B signaling in regulatory T (Treg ) lymphocytes. This hypothesis, if confirmed, may lead to further development of Treg administration-based therapies.

Mitochondrial DNA levels in Huntington disease leukocytes and dermal fibroblasts.

Huntington disease (HD) is an inherited neurodegenerative disorder caused by mutations in the huntingtin gene. Involvement of mitochondrial dysfunctions in, and especially influence of the level of mitochondrial DNA (mtDNA) on, development of this disease is unclear. Here, samples of blood from 84 HD patients and 79 controls, and dermal fibroblasts from 10 HD patients and 9 controls were analysed for mtDNA levels. Although the type of mitochondrial haplogroup had no influence on the mtDNA level, and there was no correlation between mtDNA level in leukocytes in HD patients and various parameters of HD severity, some considerable differences between HD patients and controls were identified. The average mtDNA/nDNA relative copy number was significantly higher in leukocytes, but lower in fibroblasts, of symptomatic HD patients relative to the control group. Moreover, HD women displayed higher mtDNA levels in leukocytes than HD men. Because this is the largest population analysed to date, these results might contribute to explanation of discrepancies between previously published studies concerning levels of mtDNA in cells of HD patients. We suggest that the size of the investigated population and type of cells from which DNA is isolated could significantly affect results of mtDNA copy number estimation in HD. Hence, these parameters should be taken into consideration in studies on mtDNA in HD, and perhaps also in other diseases where mitochondrial dysfunction occurs.

When do paediatric patients with familial hypercholesterolemia need statin therapy?

INTRODUCTION: Familial hypercholesterolemia (FH) is one of the most common autosomal dominant disorders. It is characterized by elevated LDL cholesterol levels occurring already by early childhood. Awareness of health risks in FH patients should incite health professionals to actively seek and treat children with lipid disorders to reduce their risk of myocardial infarction and stroke. OBJECTIVE: The aim of the study was to evaluate the suitability of taking into account the following parameters: ApoB/ApoA index, IMT and e-tracking examination, when initiating statin therapy in FH patients. Materials and methods The study included 57 male and female patients aged 9.57±3.2 years (ranging from 1 year to 17 years), diagnosed with familial hypercholesterolemia confirmed by molecular testing. All the participants had their lipid profile, ApoA and ApoB levels determined. Carotid intima-media thickness (IMT) was measured by carotid ultrasound and arterial stiffness was assessed by e-tracking. The dietary treatment efficacy was monitored in 40 patients and the 12-month combination treatment efficacy in 27 patients. The study was conducted prospectively and retrospectively. Statistical analysis was performed with the EPIINFO Ver. 7.1.1.14 statistical software package. RESULTS: Patients with familial hypercholesterolemia had high mean levels of total cholesterol and LDL cholesterol (287±67 mg/dL and 213±73 mg/dL respectively). 34.37% of the study subjects had a markedly increased ApoB/ApoA index. On IMT or e-tracking examination all the subjects (100%) had vascular abnormalities. After 6 months of a low-cholesterol diet, the mean total and LDL cholesterol levels in the serum had been reduced by 7.2% and 6.2%, respectively. Statins in an average dose of 10.42±2.49 mg daily were prescribed to 36 patients. After one year of the statin therapy, the average serum total and LDL cholesterol levels were 203.5±34.8 mg/dL and 139.1±32.1 mg/dL, respectively, and were still above the target values. Moreover, side effects of the statin therapy were monitored. An increase in AST levels seen in the study group was not statistically significant. The mean creatine kinase level was within the range of normal. Moreover, in our study material we estimated the risk of cardiovascular events in relation to the ApoB/ApoA index. Higher cardiovascular risk was found in 34.37% participants. CONCLUSIONS: Increased risk of cardiovascular events based on ApoB/ApoA index and carotid e-tracking or IMT examination in paediatric patients with FH is an indication for statin therapy initiation.

A simple modification to improve the accuracy of methylation-sensitive restriction enzyme quantitative polymerase chain reaction.

DNA digestion with endonucleases sensitive to CpG methylation such as HpaII followed by polymerase chain reaction (PCR) quantitation is commonly used in molecular studies as a simple and inexpensive solution for assessment of region-specific DNA methylation. We observed that the results of such analyses were highly overestimated if mock-digested samples were applied as the reference. We determined DNA methylation levels in several promoter regions in two setups implementing different references: mock-digested and treated with a restriction enzyme that has no recognition sites within examined amplicons. Fragmentation of reference templates allowed removing the overestimation effect, thereby improving measurement accuracy.

Chromosome 18q deletion syndrome with autoimmune diabetes mellitus: putative genomic loci for autoimmunity and immunodeficiency.

A girl with 18q deletion syndrome was diagnosed with autoimmune diabetes mellitus and Hashimoto's thyroiditis at the age of 3 yr. In addition, the girl suffered from recurrent infections due to immunoglobulin A and IgG4 deficiency. She was also found to have CD3+CD4+FoxP3+, CD3+CD4+FoxP3+CD25+, and CD3+CD4+CD25+CD127 regulatory T cells deficiency. The exceptional coincidence of the two autoimmune disorders occurring at an early age, and associated with immune deficiency, implies that genes located on deleted 19.4 Mbp region at 18q21.32-q23 (chr18:58,660,699-78,012,870) might play a role in the pathogenesis of autoimmunity leading to ß cell destruction and diabetes.

Diagnosis of Mastocytosis in Children and Adults in Daily Clinical Practice.

Mastocytosis comprises a heterogeneous group of disorders characterized by clonal, neoplastic proliferation of mast cells accumulating in one or multiple organs. In the majority of cases skin involvement is the first clinical manifestation of the disease. Clinical work-up consists of a combination of morphological, immunohistochemical, flow cytometric immunophenotyping and molecular examination. Cutaneous mastocytosis predominates in children, whereas systemic mastocytosis is the most common form of the disease in adults. Therefore, different diagnostic algorithms have to be applied in adult patients and children with suspected mastocytosis. This comprehensive review presents currently defined variants of the disease and recommendations to facilitate diagnostic work-up in children and adults with suspected mastocytosis in daily clinical practice.

Co-incidence of Turner syndrome and Duchenne muscular dystrophy - an important problem for the clinician.

INTRODUCTION: Turner syndrome is a relatively common chromosomal disorder which affects about one in 2000 live born females. Duchenne muscular dystrophy is an X-linked recessive disorder affecting 1:3600 live born males. Considering the above, the coexistence of these two diseases may occur only anecdotally. CASE PRESENTATION: Here, we report a 4 ½ year-old female with classical 45,X Turner syndrome who also had Duchenne muscular dystrophy caused by a point mutation in the dystrophin gene (c.9055delG). The patient showed the typical phenotype of Turner syndrome including distinctive dysmorphic features (short neck, low posterior hairline, wide position of nipples), aortic coarctation and feet lymphedema. Besides, she presented with an unusually early beginning of muscular dystrophy symptoms with infantile-onset motor developmental delay, intellectual disability and early calf muscular hypertrophy. CONCLUSION: The coexistence of an X-linked recessive disorder should be considered in women affected by Turner syndrome presenting with additional atypical clinical features.

Concurrent DNA Copy-Number Alterations and Mutations in Genes Related to Maintenance of Genome Stability in Uninvolved Mammary Glandular Tissue from Breast Cancer Patients.

Somatic mosaicism for DNA copy-number alterations (SMC-CNAs) is defined as gain or loss of chromosomal segments in somatic cells within a single organism. As cells harboring SMC-CNAs can undergo clonal expansion, it has been proposed that SMC-CNAs may contribute to the predisposition of these cells to genetic disease including cancer. Herein, the gross genomic alterations (>500 kbp) were characterized in uninvolved mammary glandular tissue from 59 breast cancer patients and matched samples of primary tumors and lymph node metastases. Array-based comparative genomic hybridization showed 10% (6/59) of patients harbored one to 359 large SMC-CNAs (mean: 1,328 kbp; median: 961 kbp) in a substantial portion of glandular tissue cells, distal from the primary tumor site. SMC-CNAs were partially recurrent in tumors, albeit with considerable contribution of stochastic SMC-CNAs indicating genomic destabilization. Targeted resequencing of 301 known predisposition and somatic driver loci revealed mutations and rare variants in genes related to maintenance of genomic integrity: BRCA1 (p.Gln1756Profs*74, p.Arg504Cys), BRCA2 (p.Asn3124Ile), NCOR1 (p.Pro1570Glnfs*45), PALB2 (p.Ser500Pro), and TP53 (p.Arg306*). Co-occurrence of gross SMC-CNAs along with point mutations or rare variants in genes responsible for safeguarding genomic integrity highlights the temporal and spatial neoplastic potential of uninvolved glandular tissue in breast cancer patients.

Dwarfism in art.

Throughout the history of mankind the birth of a child with congenital malformation raised anxiety and torment, along with attempts to explain its origins. It is possible to find relics of such events in prehistoric rock drawings and primitive sculptures, in numerous art pieces produced through the centuries up to modern sculptures, paintings and drawings. The aim of the present article is to show how dwarfs were portrayed in a variety of art forms at different moments in the history of our world.

Sex contribution to average age at onset of Huntington's disease depends on the number of (CAG)n repeats.

Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by the extension of the CAG repeats in exon 1 of the HTT gene and is transmitted in a dominant manner. The present study aimed to assess whether patients' sex, in the context of mutated and normal allele length, contributes to age on onset (AO) of HD. The study population comprised a large cohort of 3723 HD patients from the European Huntington's Disease Network's REGISTRY database collected at 160 sites across 17 European countries and in one location outside Europe. The data were analyzed using regression models and factorial analysis of variance (ANOVA) considering both mutated allele length and sex as predictors of patients' AO. AO, as described by the rater's estimate, was found to be later in affected women than in men across the whole population. This difference was most pronounced in a subgroup of 1273 patients with relatively short variants of the mutated allele (40-45 CAG repeats) and normal alleles in a higher half of length distribution-namely, more than 17 CAG repeats; however, it was also observed in each group. Our results presented in this observational study point to sex-related differences in AO, most pronounced in the presence of the short mutated and long normal allele, which may add to understanding the dynamics of AO in Huntington's Disease.Trial registration: ClinicalTrials.gov identifier NCT01590589.

High Resolution Melting analysis as a rapid and efficient method of screening for small mutations in the STK11 gene in patients with Peutz-Jeghers syndrome.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare hereditary syndrome characterized by the occurrence of hamartomatous polyps in the gastrointestinal tract, mucocutaneous pigmentation and increased risk of cancer in multiple internal organs. Depending on the studied population, its incidence has been estimated to range from 1:200 000 even up to 1:50 000 births. Being an autosomal disease, PJS is caused in most cases by mutations in the STK11 gene. METHODS: The majority of causative DNA changes identified in patients with PJS are small mutations and, therefore, developing a method of their detection is a key aspect in the advancement of genetic diagnostics of PJS patients. We designed 13 pairs of primers, which amplify at the same temperature and enable examination of all coding exons of the STK11 gene by the HRM analysis. RESULTS: In our group of 41 families with PJS small mutations of the STK11 gene were detected in 22 families (54%). In the remaining cases all of the coding exons were sequenced. However, this has not allowed to detect any additional mutations. CONCLUSIONS: The developed methodology is a rapid and cost-effective screening tool for small mutations in PJS patients and makes it possible to detect all the STK11 gene sequence changes occurring in this group.

Epidemiology of isolated preaxial polydactyly type I: data from the Polish Registry of Congenital Malformations (PRCM).

BACKGROUND: Polydactyly represents a heterogeneous group of congenital hand and foot anomalies with variable clinical features and diverse etiology. Preaxial polydactyly type I (PPD1) is the most frequent form of preaxial polydactyly. The etiology of sporadic PPD1 remains largely unknown and the relative contribution of genetic and environmental factors is not clearly defined. The primary goals of this study are twofold: (1) to examine the epidemiology and clinical features of sporadic PPD1 in comparison to a healthy control group, and (2) to contrast the characteristics of sporadic PPD1 with familial forms of isolated polydactyly. METHODS: Among 2,530,349 live births registered in the Polish Registry of Congenital Malformations (PRCM), we identified 459 children with isolated sporadic PPD1 and 353 children with familial polydactyly, including 57 children with familial PPD1. RESULTS: In comparison with the matched group of 303 controls, sporadic PPD1 cases had significantly lower birth order (P = 0.01) and birthweight (P < 0.0001). Similarly, when compared to familial cases of polydactyly, lower birth order (P = 0.047) and lower birthweight (P < 0.0001) were characteristic of sporadic PPD1 cases. Moreover, our analyses suggested several additional risk factors for sporadic PPD1, including lower paternal education levels (P = 0.01), upper respiratory tract infections during the first trimester of pregnancy (P = 0.049), and maternal history of epilepsy (P = 0.01). CONCLUSIONS: In summary, our study provides support to the hypothesis that non-genetic factors play an important role in the etiology of non-familiar PPD1.

Primary leiomyosarcoma of the mesentery in two sisters: clinical and molecular characteristics.

Mesenteric leiomyosarcoma (LMS) is a very rare malignancy whose familiar occurrence has not yet been reported. We present two sisters who developed intestinal LMS. Pathological analysis of the tumor samples, including evaluation of smooth muscle actin+, desmin+, Myf4-, DOG-1-, S100-, CD34- and CD117- confirmed LMS diagnosis. Molecular analysis of the lesions, both primary tumors and a liver metastasis, revealed several genomic imbalances, with recurrent chromosomal aberration: interstitial gain at chromosome 17p11.2-13.1 with the minimal overlapping region of 9.2 Mb. Our study provides further evidence for the significant role of the genes located in this region in the early stage of carcinogenesis.

Conversion of epidermal growth factor receptor 2 and hormone receptor expression in breast cancer metastases to the brain.

INTRODUCTION: We investigated the status of estrogen receptor alpha (ERα), progesterone receptor (PR), and epidermal growth factor receptor 2 (HER2) in primary tumor and in the corresponding brain metastases in a consecutive series of breast cancer patients. Additionally, we studied factors potentially influencing conversion and evaluated its association with survival. METHODS: The study group included 120 breast cancer patients. ERα, PR, and HER2 status in primary tumors and in matched brain metastases was determined centrally by immunohistochemistry and/or fluorescence in situ hybridization. RESULTS: Using the Allred score of ≥ 3 as a threshold, conversion of ERα and PR in brain metastases occurred in 29% of cases for both receptors, mostly from positive to negative. Conversion of HER2 occurred in 14% of patients and was more balanced either way. Time to brain relapse and the use of chemotherapy or trastuzumab did not influence conversion, whereas endocrine therapy induced conversion of ERα (P = 0.021) and PR (P = 0.001), mainly towards their loss. Receptor conversion had no significant impact on survival. CONCLUSIONS: Receptor conversion, particularly loss of hormone receptors, is a common event in brain metastases from breast cancer, and endocrine therapy may increase its incidence. Receptor conversion does not significantly affect survival.

Cancer predisposing BARD1 mutations in breast-ovarian cancer families.

The breast cancer susceptibility gene BARD1 (BRCA1-associated RING domain protein, MIM# 601593) acts with BRCA1 in DNA double-strand break (DSB) repair and also in apoptosis initiation. We screened 109 BRCA1/2 negative high-risk breast and/or ovarian cancer patients from North-Eastern Poland for BARD1 germline mutations using a combination of denaturing high-performance liquid chromatography and direct sequencing. We identified 16 different BARD1 sequence variants, five of which are novel. Three of them were suspected to be pathogenic, including a protein truncating nonsense mutation (c.1690C>T, p.Gln564X), a splice mutation (c.1315-2A>G) resulting in exon 5 skipping, and a silent change (c.1977A>G) which alters several exonic splicing enhancer motifs in exon 10 and results in a transcript lacking exons 2-9. Our findings suggest that BARD1 mutations may be regarded as cancer risk alleles and warrant further investigation to determine their actual contribution to non-BRCA1/2 breast and ovarian cancer families.

Cornelia de Lange syndrome with NIPBL mutation and mosaic Turner syndrome in the same individual.

BACKGROUND: Cornelia de Lange syndrome (CdLS) is a dominantly inherited disorder characterized by facial dysmorphism, growth and cognitive impairment, limb malformations and multiple organ involvement. Mutations in NIPBL gene account for about 60% of patients with CdLS. This gene encodes a key regulator of the Cohesin complex, which controls sister chromatid segregation during both mitosis and meiosis. Turner syndrome (TS) results from the partial or complete absence of one of the X chromosomes, usually associated with congenital lymphedema, short stature, and gonadal dysgenesis. CASE PRESENTATION: Here we report a four-year-old female with CdLS due to a frameshift mutation in the NIPBL gene (c.1445_1448delGAGA), who also had a tissue-specific mosaic 45,X/46,XX karyotype. The patient showed a severe form of CdLS with craniofacial dysmorphism, pre- and post-natal growth delay, cardiovascular abnormalities, hirsutism and severe psychomotor retardation with behavioural problems. She also presented with minor clinical features consistent with TS, including peripheral lymphedema and webbed neck. The NIPBL mutation was present in the two tissues analysed from different embryonic origins (peripheral blood lymphocytes and oral mucosa epithelial cells). However, the percentage of cells with monosomy X was low and variable in tissues. These findings indicate that, ontogenically, the NIPBL mutation may have appeared before the mosaic monosomy X. CONCLUSIONS: The coexistence in several patients of these two rare disorders raises the issue of whether there is indeed a cause-effect association. The detailed clinical descriptions indicate predominant CdLS phenotype, although additional TS manifestations may appear in adolescence.

The outcome and predictive factors of sunitinib therapy in advanced gastrointestinal stromal tumors (GIST) after imatinib failure - one institution study.

BACKGROUND: Gastrointestinal stromal tumors (GIST) mutational status is recognized factor related to the results of tyrosine kinase inhibitors therapy such as imatinib (IM) or sunitinib (SU). Arterial hypertension (AH) is common adverse event related to SU, reported as predictive factor in renal cell carcinoma. The aim of the study was to analyze the outcomes and factors predicting results of SU therapy in inoperable/metastatic CD117(+) GIST patients after IM failure. METHODS: We identified 137 consecutive patients with advanced inoperable/metastatic GIST treated in one center with SU (2nd line treatment). Median follow-up time was 23 months. Additionally, in 39 patients there were analyzed selected constitutive single nucleotide polymorphisms (SNPs) of VEGFA and VEGFR2 genes. RESULTS: One year progression-free survival (PFS; calculated from the start of SU) rate was 42% and median PFS was 43 weeks. The estimated overall survival (OS, calculated both from start of SU or IM) was 74 weeks and 51 months, respectively. One-year PFS was 65% (median 74 weeks) in 55 patients with AH vs. 22% (median 17 weeks) in patients without AH. Patients with primary tumors carrying mutations in KIT exon 9 or wild-type had substantially better 1-year PFS (68% and 57%; median 65.5 and 50.5 weeks, respectively) than patients having tumors with KIT exon 11 or PDGFRA mutations (34% and 15%; median 36.8 and 9 weeks, respectively). We identified two independent factors with significant impact on PFS and OS in univariate and multivariate analysis: primary tumor genotype and presence of AH. The most common adverse events during therapy were: fatigue, AH, hypothyroidism, hand and foot syndrome, mucositis, skin reactions, dyspepsia, and diarrhea. Two deaths were assessed as related to tumor rupture caused by reaction to SU therapy. The presence of C-allele in rs833061 and the T-allele in rs3025039 polymorphism of VEGFA were associated with significantly higher risk of hypothyroidism (OR: 10.0 p = 0.041 and OR: 10.5; p = 0.015, respectively). CONCLUSIONS: We confirmed that many advanced GIST patients benefit from SU therapy with OS > 1.5 year. Primary tumor KIT/PDGFRA genotype and SU-induced AH, as surrogate of its antiangiogenic activity are two independent factors influencing both PFS and OS.

Regeneration of comparative genomic hybridization oligonucleotide microarrays with dimethylurea.

Reuse of materials in DNA hybridization-based methods has been known since the advent of Southern membranes. Array-based comparative genomic hybridization is essentially Southern hybridization with multiple probes immobilized on a solid surface. We show that comparative genomic hybridization microarrays fabricated with maskless array synthesizer technology can be used up to four times with the application of 1,3-dimethylurea as an array-stripping agent. We reproducibly detected chromosomal aberrations (0.6-22.4Mb in size) in four hybridization rounds using regenerated microarray slides. We also demonstrated that regenerated arrays can detect smaller alterations (16-200kbp), such as common copy number variants, as well as complex aberration profiles in tumor DNA.

Routine brush cytology and fluorescence in situ hybridization for assessment of pancreatobiliary strictures.

BACKGROUND: The specificity of brush cytology for detection of malignant pancreatobiliary strictures is high, but its sensitivity is moderate. Fluorescence in situ hybridization (FISH) can be used to detect chromosomal aneuploidy in biliary brushing specimens, and, according to some reports, it may improve the sensitivity of routine cytology. OBJECTIVE: To assess the role of routine cytology and FISH in detection of malignant pancreatobiliary strictures. DESIGN: Prospective study performed between September 2008 and August 2010. SETTING: University hospital. PATIENTS: This study involved 81 patients with bile duct or pancreatic duct strictures. INTERVENTION: Brush cytology obtained during ERCP from pancreatic duct or bile duct strictures and analysis of smears by routine cytology and FISH. MAIN OUTCOME MEASUREMENTS: Sensitivity, specificity, and positive and negative predictive values of routine cytology and FISH calculated with a 95% confidence interval. RESULTS: The sensitivity of routine cytology was 35.19%, and specificity was 100%. When atypia was identified as positive, the resultant sensitivity was 53.7%, and specificity was 100%. Sensitivity of FISH was 51.85%, and specificity was 88.89%. When either routine cytology was positive or atypia was observed or when the FISH result was positive, sensitivity was the highest (72.22%), and it was statistically significant in comparison with both routine cytology with atypia (P < .036) and FISH (P < .023), but specificity was lower than that of routine cytology (88.89% vs 100%). LIMITATIONS: Use of a DNA probe set that was designed for detection of urothelial carcinoma. Limited number of patients. CONCLUSION: FISH improved the sensitivity of routine cytology. Pancreatic duct brushings were a reliable material for detection of chromosomal abnormalities by FISH. The best diagnostic result was achieved by combining routine cytology with FISH.