Arvydas Laurinavicius - Academia.edu (original) (raw)

Papers by Arvydas Laurinavicius

Diagnostic …, 2012

Background: Molecular studies of breast cancer revealed biological heterogeneity of the disease a... more Background: Molecular studies of breast cancer revealed biological heterogeneity of the disease and opened new perspectives for personalized therapy. While multiple gene expression-based systems have been developed, current clinical practice is largely based upon conventional clinical and pathologic criteria. This gap may be filled by development of combined multi-IHC indices to characterize biological and clinical behaviour of the tumours. Digital image analysis (DA) with multivariate statistics of the data opens new opportunities in this field. Methods: Tissue microarrays of 109 patients with breast ductal carcinoma were stained for a set of 10 IHC markers (ER, PR, HER2, Ki67, AR, BCL2, HIF-1α, SATB1, p53, and p16). Aperio imaging platform with the Genie, Nuclear and Membrane algorithms were used for the DA. Factor analysis of the DA data was performed in the whole group and hormone receptor (HR) positive subgroup of the patients (n = 85). Results: Major factor potentially reflecting aggressive disease behaviour (i-Grade) was extracted, characterized by opposite loadings of ER/PR/AR/BCL2 and Ki67/HIF-1α. The i-Grade factor scores revealed bimodal distribution and were strongly associated with higher Nottingham histological grade (G) and more aggressive intrinsic subtypes. In HR-positive tumours, the aggressiveness of the tumour was best defined by positive Ki67 and negative ER loadings. High Ki67/ER factor scores were strongly associated with the higher G and Luminal B types, but also were detected in a set of G1 and Luminal A cases, potentially indicating high risk patients in these categories. Inverse relation between HER2 and PR expression was found in the HR-positive tumours pointing at differential information conveyed by the ER and PR expression. SATB1 along with HIF-1α reflected the second major factor of variation in our patients; in the HR-positive group they were inversely associated with the HR and BCL2 expression and represented the major factor of variation. Finally, we confirmed high expression levels of p16 in Triple-negative tumours. Conclusion: Factor analysis of multiple IHC biomarkers measured by automated DA is an efficient exploratory tool clarifying complex interdependencies in the breast ductal carcinoma IHC profiles and informative value of single IHC markers. Integrated IHC indices may provide additional risk stratifications for the currently used grading systems and prove to be useful in clinical outcome studies.

Proliferative activity, assessed by Ki67 immunohistochemistry (IHC), is an established prognostic... more Proliferative activity, assessed by Ki67 immunohistochemistry (IHC), is an established prognostic and predictive biomarker of breast cancer (BC). However, it remains under-utilized due to lack of standardized robust measurement methodologies and significant intratumor heterogeneity of expression. A recently proposed methodology for IHC biomarker assessment in whole slide images (WSI), based on systematic subsampling of tissue information extracted by digital image analysis (DIA) into hexagonal tiling arrays, enables computation of a comprehensive set of Ki67 indicators, including intratumor variability. In this study, the tiling methodology was applied to assess Ki67 expression in WSI of 152 surgically removed Ki67-stained (on full-face sections) BC specimens and to test which, if any, Ki67 indicators can predict overall survival (OS). Visual Ki67 IHC estimates and conventional clinico-pathologic parameters were also included in the study. Analysis revealed linearly independent intrinsic factors of the Ki67 IHC variance: proliferation (level of expression), disordered texture (entropy), tumor size and Nottingham Prognostic Index, bimodality, and correlation. All visual and DIA-generated indicators of the level of Ki67 expression provided significant cutoff values as single predictors of OS. However, only bimodality indicators (Ashman's D, in particular) were independent predictors of OS in the context of hormone receptor and HER2 status. From this, we conclude that spatial heterogeneity of proliferative tumor activity, measured by DIA of Ki67 IHC expression and analyzed by the hexagonal tiling approach, can serve as an independent prognostic indicator of OS in BC patients that outperforms the prognostic power of the level of proliferative activity.

Diagnostic pathology, 2014

Digital immunohistochemistry (IHC) is one of the most promising applications brought by new gener... more Digital immunohistochemistry (IHC) is one of the most promising applications brought by new generation image analysis (IA). While conventional IHC staining quality is monitored by semi-quantitative visual evaluation of tissue controls, IA may require more sensitive measurement. We designed an automated system to digitally monitor IHC multi-tissue controls, based on SQL-level integration of laboratory information system with image and statistical analysis tools. Consecutive sections of TMA containing 10 cores of breast cancer tissue were used as tissue controls in routine Ki67 IHC testing. Ventana slide label barcode ID was sent to the LIS to register the serial section sequence. The slides were stained and scanned (Aperio ScanScope XT), IA was performed by the Aperio/Leica Colocalization and Genie Classifier/Nuclear algorithms. SQL-based integration ensured automated statistical analysis of the IA data by the SAS Enterprise Guide project. Factor analysis and plot visualizations were...

Diagnostic pathology, 2011

Collaborative Digital Anatomic Pathology refers to the use of information technology that support... more Collaborative Digital Anatomic Pathology refers to the use of information technology that supports the creation and sharing or exchange of information, including data and images, during the complex workflow performed in an Anatomic Pathology department from specimen reception to report transmission and exploitation. Collaborative Digital Anatomic Pathology can only be fully achieved using medical informatics standards. The goal of the international integrating the Healthcare Enterprise (IHE) initiative is precisely specifying how medical informatics standards should be implemented to meet specific health care needs and making systems integration more efficient and less expensive.

Oncotarget, Jan 15, 2015

Biological diversity of breast cancer presents challenges for personalized therapy and necessitat... more Biological diversity of breast cancer presents challenges for personalized therapy and necessitates multiparametric approaches to understand and manage the disease. Multiple protein biomarkers tested by immunohistochemistry (IHC), followed by digital image analysis and multivariate statistics of the data, have been shown to be effective in exploring latent profiles of tumor tissue immunophenotype. In this study, based on tissue microarrays of 107 patients with hormone receptor (HR) positive invasive ductal breast carcinoma, we investigated the prognostic value of the integrated immunophenotype to predict overall survival (OS) of the patients. A set of 10 IHC markers (ER, PR, HER2, Ki67, AR, BCL2, HIF-1α, SATB1, p53, and p16) was used. The main factor of the variance was characterized by opposite loadings of ER/PR/AR/BCL2 and Ki67/HIF-1α; it was associated with histological grade but did not predict OS. The second factor was driven by SATB1 expression along with moderate positive HIF...

Virchows Archiv, 2015

Digital image analysis (DIA) enables higher accuracy, reproducibility, and capacity to enumerate ... more Digital image analysis (DIA) enables higher accuracy, reproducibility, and capacity to enumerate cell populations by immunohistochemistry; however, the most unique benefits may be obtained by evaluating the spatial distribution and intra-tissue variance of markers. The proliferative activity of breast cancer tissue, estimated by the Ki67 labeling index (Ki67 LI), is a prognostic and predictive biomarker requiring robust measurement methodologies. We performed DIA on whole-slide images (WSI) of 302 surgically removed Ki67-stained breast cancer specimens; the tumour classifier algorithm was used to automatically detect tumour tissue but was not trained to distinguish between invasive and non-invasive carcinoma cells. The WSI DIA-generated data were subsampled by hexagonal tiling (HexT). Distribution and texture parameters were compared to conventional WSI DIA and pathology report data. Factor analysis of the data set, including total numbers of tumor cells, the Ki67 LI and Ki67 distribution, and texture indicators, extracted 4 factors, identified as entropy, proliferation, bimodality, and cellularity. The factor scores were further utilized in cluster analysis, outlining subcategories of heterogeneous tumors with predominant entropy, bimodality, or both at different levels of proliferative activity. The methodology also allowed the visualization of Ki67 LI heterogeneity in tumors and the automated detection and quantitative evaluation of Ki67 hotspots, based on the upper quintile of the HexT data, conceptualized as the &amp;amp;amp;quot;Pareto hotspot&amp;amp;amp;quot;. We conclude that systematic subsampling of DIA-generated data into HexT enables comprehensive Ki67 LI analysis that reflects aspects of intra-tumor heterogeneity and may serve as a methodology to improve digital immunohistochemistry in general.

Diagnostic Pathology

Molecular Cancer Research, 2013

Studies in health technology and informatics, 2009

Extremely large medical images, like ones of virtual slide microscopy, are beyond some limitation... more Extremely large medical images, like ones of virtual slide microscopy, are beyond some limitations of the DICOM standard (e.g., a 4 Gbyte barrier, caused by 32-bit architecture). Some solutions and trade-offs have been already proposed and included in the DICOM standard (e.g., usage of JPEG2000 image compression standard, JPEG2000 interactive protocol [JPIP] and division of the images into smaller parts for placing them in the PACS). These new features lead to implementation of alternative interaction solutions simultaneously in the same PACS to serve both images of typical size (e.g., radiological) and large size virtual slide microscopy images. The paper deals with problems of (a) constructing a data and interaction model of images within PACS, (b) searching for criteria to assess image content complexity and to reach an efficient division of virtual slide microscopy images into tiles; (c) providing both the conventional DICOM services and the image interchange using JPIP.

Studies in health technology and informatics, 2012

New opportunities and the adoption of digital technologies will transform the way pathology profe... more New opportunities and the adoption of digital technologies will transform the way pathology professionals and services work. Many areas of our daily life as well as medical professions have experienced this change already which has resulted in a paradigm shift in many activities. Pathology is an image-based discipline, therefore, arrival of digital imaging into this domain promises major shift in our work and required mentality. Recognizing the physical and digital duality of the pathology workflow, we can prepare for the imminent increase of the digital component, synergize and enjoy its benefits. Development of a new generation of laboratory information systems along with seamless integration of digital imaging, decision-support, and knowledge databases will enable pathologists to work in a distributed environment. The paradigm of "cloud pathology" is proposed as an ultimate vision of digital pathology workstations plugged into the integrated multidisciplinary patient ca...

The Journal of Urology, 2014

Patients with prostate cancer who have biochemical recurrence after curative therapy are at highe... more Patients with prostate cancer who have biochemical recurrence after curative therapy are at higher risk for distant metastasis and cancer specific death. Assessment of aberrant DNA methylation in urine might complement currently used clinical prognostic factors and serve as a noninvasive tool for early prediction of biochemical recurrence after radical prostatectomy. Promoter methylation of 7 genes was evaluated by methylation sensitive polymerase chain reaction in 149 prostate cancer tissues, 37 noncancerous prostate tissues and 17 benign prostatic hyperplasia samples. Quantitative polymerase chain reaction was used for DNA methylation analysis of the urine of 253 patients with prostate cancer and 32 with benign prostatic hyperplasia. In prostate cancer tissue the most frequently methylated genes were RASSF1, GSTP1 and RARB, which combined were positively identified in 85% of cases. These genes were also methylated in the urine of 60% of patients with prostate cancer. RASSF1 was methylated in 45% of prostate cancer urine samples with methylation intensity significantly higher in prostate cancer than in benign prostatic hyperplasia cases (p = 0.018). In a univariate model RASSF1 methylation and the total number of methylated genes in prostate cancer tissue were predictive of time to biochemical recurrence (p = 0.019 and 0.043, respectively). On multivariate analysis RASSF1 methylation together with pathological stage was the most significant predictor of biochemical recurrence in patients with Gleason score 6 tumors when analyzed in tissue and urine (p ≤0.001). Hypermethylation of RASSF1 in cancerous tissue and urine from patients with prostate cancer correlated with biochemical recurrence after radical prostatectomy. The prognostic potential of this biomarker deserves further investigation.

Oncology Letters, 2014

The aim of this retrospective pilot study was to evaluate the Aperio nuclear V9 algorithm as an i... more The aim of this retrospective pilot study was to evaluate the Aperio nuclear V9 algorithm as an image analysis tool to observe the histopathological changes of ocular surface squamous neoplasia (OSSN). A histopathological assessment, including the Ki-67 proliferative index (PI) of immunohistochemically-stained tumor conjunctiva (TC) and healthy conjunctiva (HC) tissues, was performed in six cases of OSSN. The Aperio V9 algorithm was applied to digital images of the tissue specimens to count the Ki-67 PI and to measure the nuclear area indices. This digital algorithm was validated using stereological and visual analysis methods. The visual scoring of Ki-67 PI ranged from 22 to 60% (mean, 38.5%), and from 5 to 20% (mean 9.5%) in TC and HC tissue, respectively. The computer-aided analysis, using the Aperio nuclear V9 algorithm, revealed that the Ki-67 PI ranged from 21.5 to 43.5% (mean, 33.6%), and from 1.9 to 21.0% (mean, 11.8%) in the TC and HC tissue, respectively. The stereological method demonstrated that the Ki-67 PI ranged from 30.1 to 51.5% (mean, 41.0%), and from 3.2 to 30.1% (mean, 15.1%) in the TC and HC tissues, respectively. The strongest association in the collinearity of regression analysis was observed between the Aperio nuclear V9 algorithm/stereological models in the TC tissue (r 2 =0.7; P=0.04) and the HC tissue (r 2 =0.7; P=0.03), and the visual/stereological models in the TC tissue (r 2 =0.7; P=0.04) and the visual/Aperio nuclear V9 algorithm models in the HC tissue (r 2 =0.7; P=0.04). A weak and statistically insignificant association was identified between the visual/Aperio nuclear V9 algorithm analysis in the TC tissue (r 2 =0.4; P=0.2) and the visual/stereological models in the HC tissue (r 2 =0.5; P=0.13). No significant difference was observed between the nuclear area of the TC (mean, 36.5 µm 2 ) and HC (mean, 35.7 µm 2 ; P=0.88) tissues. It was concluded that the Aperio nuclear V9 algorithm is a useful tool for the reliable analysis of histopathological changes of OSSN. The results of this computer-aided algorithm correlate strongly with the stereological method when assessing the Ki-67 PI.

Diagnostic Pathology, 2013

Diagnostic pathology, 2014

Pediatric Nephrology, 2004

Constitutional missense mutations in the WT1 gene are usually associated with the Denys-Drash syn... more Constitutional missense mutations in the WT1 gene are usually associated with the Denys-Drash syndrome, characterized by a rapid progressive nephropathy, male pseudohermaphroditism, and an increased risk for Wilms tumor. We report here a patient with scrotal hypospadias and a slow progressive nephropathy due to focal and segmental glomerulosclerosis. WT1 mutation analysis revealed a constitutional missense mutation in exon 9 resulting in an exchange F392L. This mutation has previously been reported by others in a patient with a similar mild course of nephropathy. In contrast, a mutation in the corresponding codon of exon 8 (F364L) was previously found by us in a patient with a very rapid progression to end-stage renal disease. Whether the position of a mutation may influence the course of the nephropathy must be evaluated in a larger patient cohort. The individual tumor risk for this alteration cannot be given at present because neither of the two patients has shown evidence of a Wilms tumor or a gonadoblastoma to date.

NeuroReport, 1999

DNA methylation was investigated in the putative promoter region of the human dopamine D2 recepto... more DNA methylation was investigated in the putative promoter region of the human dopamine D2 receptor gene (DRD2). Twenty-two DNA samples from two types of cells differentially expressing D2 receptors, striatum and lymphocytes, were subjected to bisulphite modification-based mapping of methylated cytosines. In the tested region, the DNA from lymphocytes exhibited a significantly higher degree of methylation than that from striata. In addition, a significantly higher proportion of methylated to unmethylated cytosines was detected in DRD2 from the right than the left striatum, and a trend towards a greater degree of methylation was detected in older than in younger individuals. These DRD2 methylation findings are consistent with dopamine D2 receptor binding data from the literature which support the idea that DNA methylation plays a role in regulation of DRD2 expression.

Kidney International, 1999

Journal of Biomedical Optics, 2011

Fourier transform infrared (FTIR) spectroscopic imaging has been used to probe the biochemical co... more Fourier transform infrared (FTIR) spectroscopic imaging has been used to probe the biochemical composition of human renal tumor tissue and adjacent normal tissue. Freshly resected renal tumor tissue from surgery was prepared as a thin cryosection and examined by FTIR spectroscopic imaging. Tissue types could be discriminated by utilizing a combination of fuzzy k-means cluster analysis and a supervised classification algorithm based on a linear discriminant analysis. The spectral classification is compared and contrasted with the histological stained image. It is further shown that renal tumor cells have spread in adjacent normal tissue. This study demonstrates that FTIR spectroscopic imaging can potentially serve as a fast and objective approach for discrimination of renal tumor tissue from normal tissue and even in the detection of tumor infiltration in adjacent tissue.

Genes, Chromosomes and Cancer, 2012

Prostate cancer (PCa) is a heterogeneous disease with diverse clinical outcomes. TMPRSS2-ERG is t... more Prostate cancer (PCa) is a heterogeneous disease with diverse clinical outcomes. TMPRSS2-ERG is the most common gene fusion in PCa, whereas activation of telomerase is a common feature of various malignancies. The aim of our study was to explore the combined utility of these and some other biomarkers in predicting biochemical recurrence after radical prostatectomy. Prostate specimens and urine sediments from 179 previously untreated patients with pT2-pT3 stage PCa were analyzed for expression of telomerase (TERT and TR) and the TMPRSS2-ERG fusion gene by means of reverse transcription PCR. Real-time PCR was used for quantification of ERG and SPINK1 expression. In total, 74% (117/158) of the prostate adenocarcinomas were positive for the TMPRSS2-ERG and/or TERT expression. Noninvasively, these transcripts were identified in 31% (19/61) of catheterized urine specimens. Significantly higher expression of ERG was detected in TMPRSS2-ERG-positive tumors (P < 0.0001), whereas more intense expression of SPINK1 was characteristic for the TMPRSS2-ERGnegative tumors (P ¼ 0.003). TERT-positive cases also had elevated levels of ERG (P ¼ 0.016), suggesting a possible link between aberrant expression of ERG and reactivation of TERT in prostate tumors. The cases negative for both transcripts, TMPRSS2-ERG and TERT, rarely recurred (P ¼ 0.014) and showed significantly longer biochemical recurrence-free period (P ¼ 0.022) as compared to the TMPRSS2-ERG and/or TERT-positive cases. The results of our study suggest that combined analysis of TMPRSS2-ERG and TERT expression can be a valuable tool for early prediction of biochemical recurrence of PCa after radical prostatectomy.

Analytical Cellular Pathology, 2014

Diagnostic …, 2012

Diagnostic pathology, 2014

Diagnostic pathology, 2011

Oncotarget, Jan 15, 2015

Virchows Archiv, 2015

Diagnostic Pathology

Molecular Cancer Research, 2013

Studies in health technology and informatics, 2009

Studies in health technology and informatics, 2012

The Journal of Urology, 2014

Oncology Letters, 2014

Diagnostic Pathology, 2013

Diagnostic pathology, 2014

Pediatric Nephrology, 2004

NeuroReport, 1999

Kidney International, 1999

Journal of Biomedical Optics, 2011

Genes, Chromosomes and Cancer, 2012

Analytical Cellular Pathology, 2014