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Featured researches published by Giedrius Lelkaitis.


International Journal of Surgery Case Reports | 2011

Myofibroblastoma of the breast: Case report and literature review.

Marco Mele; Vibeke Jensen; Adam Wronecki; Giedrius Lelkaitis

Myofibroblastoma of the breast is a rare benign mesenchymal tumor. The literature describes relatively few cases of this type of tumor. We report on a new case of myofibroblastoma in a 65-year old man successfully managed at our institution. The purpose of this case report is to highlight characteristics and differential diagnosis of this rare neoplasm.


Applied Immunohistochemistry & Molecular Morphology | 2011

Testing HER2 in Breast Cancer: A Comparative Study on BRISH, FISH, and IHC

Anja Høegh Brügmann; Giedrius Lelkaitis; Søren Nielsen; Kirsten Gadgaard Jensen; Vibeke Jensen

&NA;New brightfield in-situ hybridization (BRISH) methods based on the cohybridization of probes to the HER2 gene and chromosome 17 centromere have been developed and provide a promising alternative to fluorescence in-situ hybridization (FISH). The aim of this correlation study was to test HER2 status in primary breast carcinomas with 2 BRISH methods, FISH, and 2 immunohistochemical assays using tissue microarray technology. Materials and MethodsTissue cores (1.5 mm) were collected from 218 consecutive, archival formalin-fixed paraffin-embedded primary breast carcinomas into 4 duplicate tissue microarrays. Tumor tissue samples from 201 patients were successfully prepared in all 5 investigated methods comprising DuoCISH (Dako), Dual ISH (Ventana), HER-2 pharmDxFISH (Dako), HercepTest (Dako), and PATHWAY (4B5; Ventana). ResultsIn this study the overall agreement between Dual ISH and FISH was 98.5% with a specificity of 99% and a sensitivity of 96%. DuoCISH had an equivalent high-positive agreement with FISH (sensitivity of 96%), but a lower specificity of 93% and an overall agreement of 93% with FISH. The overall agreement between the 2 immunohistochemical methods and FISH was almost perfect (Dako HercepTest 97% and Ventana PATHWAY (4B5) 98%). With regard to specificity the 2 methods performed equally (99.4%). ConclusionsBRISH methods provide an alternative to FISH in evaluating HER2/CEN17 ratio in primary breast carcinomas. Dual ISH showed an almost perfect agreement with FISH and is a fast track method realistic to perform on all breast carcinomas. BRISH provide a permanent result that makes the method eligible for use in internal and external quality assurance.


Thyroid | 2015

Papillary thyroid carcinoma in Denmark, 1996-2008

Stefano Christian Londero; Annelise Krogdahl; Lars Bastholt; Jens Overgaard; Henrik Baymler Pedersen; Christoffer Holst Hahn; Jens Bentzen; Sten Schytte; Peer Christiansen; Oke Gerke; Christian Godballe; Lisbeth Juhler Andersen; Rune Vincents Fisker; Giedrius Lelkaitis; Mariana Kristensen

BACKGROUND Regional as well as national series show an increasing incidence of thyroid cancer largely small size papillary thyroid carcinoma (PTC). Prognostic scoring systems have been developed, but these do not take into account the rapidly changing case mix, and adjustments may be required. The purposes of this study were to evaluate treatment outcomes and to analyze the value of older prognostic scoring systems tested on a relatively new, unselected national cohort of PTC patients. METHODS This was a national prospective cohort study conducted in Denmark, which has a population of 5.5 million. RESULTS A total of 1350 patients were diagnosed with PTC during 1996-2008, and the median follow-up time was 7.9 years. The 10-year recurrence-free survival rate was 90.2%, and the 10-year crude and cause-specific survival (CSS) rates were 83.7% and 93.8% respectively. By multivariate Cox regression, it was possible to confirm age, metastases (distant and nodal), extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. In analyses of older prognostic scoring systems, a significant correlation between the risk group ranks was found for survival as well as recurrence. The c-index for CSS was highest for MACIS (0.92) and lowest for AMES (0.80). In the TNM, MACIS, and EORTC systems, most patients were classified as stage 1, and for these patients, the 10-year CSS rate was approximately 99.5%, confirming the generally excellent survival. CONCLUSION This national study provides further evidence that a favorable prognosis is to be expected for patients diagnosed with PTC. Also, it was possible to confirm age, metastases, extrathyroidal extension, and tumor size as predictors of mortality, whereas only nodal metastases, extrathyroidal extension, and tumor size were predictors of recurrence. All the scoring systems evaluated were able to produce a highly significant risk group stratification, showing that in spite of the changes in the case mix of PTC, these systems are still applicable, and in fact contain valuable prognostic information useable for treatment planning.


Oncotarget | 2017

uPAR-targeted optical near-infrared (NIR) fluorescence imaging and PET for image-guided surgery in head and neck cancer: proof-of-concept in orthotopic xenograft model.

Anders Christensen; Karina Juhl; Morten Persson; Birgitte Charabi; Jann Mortensen; Katalin Kiss; Giedrius Lelkaitis; Niclas Rubek; Christian von Buchwald; Andreas Kjær

Purpose Urokinase-like Plasminogen Activator Receptor (uPAR) is overexpressed in a variety of carcinoma types, and therefore represents an attractive imaging target. The aim of this study was to assess the feasibility of two uPAR-targeted probes for PET and fluorescence tumor imaging in a human xenograft tongue cancer model. Experimental design and results Tumor growth of tongue cancer was monitored by bioluminescence imaging (BLI) and MRI. Either ICG-Glu-Glu-AE105 (fluorescent agent) or 64Cu-DOTA-AE105 (PET agent) was injected systemically, and fluorescence imaging or PET/CT imaging was performed. Tissue was collected for micro-fluorescence imaging and histology. A clear fluorescent signal was detected in the primary tumor with a mean in vivo tumor-to-background ratio of 2.5. Real-time fluorescence-guided tumor resection was possible, and sub-millimeter tumor deposits could be localized. Histological analysis showed co-localization of the fluorescent signal, uPAR expression and tumor deposits. In addition, the feasibility of uPAR-guided robotic cancer surgery was demonstrated. Also, uPAR-PET imaging showed a clear and localized signal in the tongue tumors. Conclusions This study demonstrated the feasibility of combining two uPAR-targeted probes in a preclinical head and neck cancer model. The PET modality provided preoperative non-invasive tumor imaging and the optical modality allowed for real-time fluorescence-guided tumor detection and resection. Clinical translation of this platform seems promising.


Oncotarget | 2017

Construction of a pathological risk model of occult lymph node metastases for prognostication by semi-automated image analysis of tumor budding in early-stage oral squamous cell carcinoma

Nicklas Juel Pedersen; David Hebbelstrup Jensen; Giedrius Lelkaitis; Katalin Kiss; Birgitte Charabi; Lena Specht; Christian von Buchwald

It is challenging to identify at diagnosis those patients with early oral squamous cell carcinoma (OSCC), who have a poor prognosis and those that have a high risk of harboring occult lymph node metastases. The aim of this study was to develop a standardized and objective digital scoring method to evaluate the predictive value of tumor budding. We developed a semi-automated image-analysis algorithm, Digital Tumor Bud Count (DTBC), to evaluate tumor budding. The algorithm was tested in 222 consecutive patients with early-stage OSCC and major endpoints were overall (OS) and progression free survival (PFS). We subsequently constructed and cross-validated a binary logistic regression model and evaluated its clinical utility by decision curve analysis. A high DTBC was an independent predictor of both poor OS and PFS in a multivariate Cox regression model. The logistic regression model was able to identify patients with occult lymph node metastases with an area under the curve (AUC) of 0.83 (95% CI: 0.78–0.89, P <0.001) and a 10-fold cross-validated AUC of 0.79. Compared to other known histopathological risk factors, the DTBC had a higher diagnostic accuracy. The proposed, novel risk model could be used as a guide to identify patients who would benefit from an up-front neck dissection.


Acta Oncologica | 2018

Standardized assessment of tumor-infiltrating lymphocytes in breast cancer: an evaluation of inter-observer agreement between pathologists

Trine Tramm; Tina Di Caterino; Anne-Marie B Jylling; Giedrius Lelkaitis; Anne-Vibeke Laenkholm; Péter Ragó; Tomasz Piotr Tabor; Maj-Lis Møller Talman; Emmanouela Vouza

Abstract Introduction: In breast cancer, there is a growing body of evidence that tumor-infiltrating lymphocytes (TILs) may have clinical utility and may be able to direct clinical decisions for subgroups of patients. Clinical utility is, however, not sufficient for warranting the implementation of a new biomarker in the routine practice, and evaluation of the analytical validity is needed, including testing the reproducibility of decentralized assessment of TILs. The aim of this study was to evaluate the inter-observer agreement of TILs assessment using a standardized method, as proposed by the International TILs Working Group 2014, applied to a cohort of breast cancers reflecting an average breast cancer population. Material and methods: Stromal TILs were assessed using full slide sections from 124 breast cancers with varying histology, malignancy grade and ER- and HER2 status. TILs were estimated by nine dedicated breast pathologists using scanned hematoxylin–eosin stainings. TILs results were categorized using various cutoffs, and the inter-observer agreement was evaluated using the intraclass coefficient (ICC), Kappa statistics as well as individual overall agreements with the median value of TILs. Results: Evaluation of TILs led to an ICC of 0.71 (95% CI: 0.65–0.77) corresponding to an acceptable agreement. Kappa values were in the range of 0.38–0.46 corresponding to a fair to moderate agreement. The individual agreements increased, when using only two categories (‘high’ vs. ‘low’ TILs) and a cutoff of 50–60%. Discussion: The results of the present study are in accordance with previous studies, and shows that the proposed methodology for standardized evaluation of TILs renders an acceptable inter-observer agreement. The findings, however, indicate that assessment of TILs needs further refinement, and is in support of the latest St. Gallen Consensus, that routine reporting of TILs for early breast cancer is not ready for implementation in a clinical setting.


Acta Oncologica | 2018

An inter-observer Ki67 reproducibility study applying two different assessment methods : on behalf of the Danish Scientific Committee of Pathology, Danish breast cancer cooperative group (DBCG)

Anne-Vibeke Laenkholm; Dorthe Grabau; Maj Lis Møller Talman; Eva Balslev; Anne Marie Bak Jylling; Tomasz Piotr Tabor; Morten Johansen; Anja Høegh Brügmann; Giedrius Lelkaitis; Tina Di Caterino; Henrik Mygind; Thomas Poulsen; Henrik Mertz; Gorm Søndergaard; Birgitte Bruun Rasmussen

Abstract Introduction: In 2011, the St. Gallen Consensus Conference introduced the use of pathology to define the intrinsic breast cancer subtypes by application of immunohistochemical (IHC) surrogate markers ER, PR, HER2 and Ki67 with a specified Ki67 cutoff (>14%) for luminal B-like definition. Reports concerning impaired reproducibility of Ki67 estimation and threshold inconsistency led to the initiation of this quality assurance study (2013–2015). The aim of the study was to investigate inter-observer variation for Ki67 estimation in malignant breast tumors by two different quantification methods (assessment method and count method) including measure of agreement between methods. Material and methods: Fourteen experienced breast pathologists from 12 pathology departments evaluated 118 slides from a consecutive series of malignant breast tumors. The staining interpretation was performed according to both the Danish and Swedish guidelines. Reproducibility was quantified by intra-class correlation coefficient (ICC) and Lights Kappa with dichotomization of observations at the larger than (>) 20% threshold. The agreement between observations by the two quantification methods was evaluated by Bland–Altman plot. Results: For the fourteen raters the median ranged from 20% to 40% by the assessment method and from 22.5% to 36.5% by the count method. Light’s Kappa was 0.664 for observation by the assessment method and 0.649 by the count method. The ICC was 0.82 (95% CI: 0.77–0.86) by the assessment method vs. 0.84 (95% CI: 0.80–0.87) by the count method. Conclusion: Although the study in general showed a moderate to good inter-observer agreement according to both ICC and Lights Kappa, still major discrepancies were identified in especially the mid-range of observations. Consequently, for now Ki67 estimation is not implemented in the DBCG treatment algorithm.


Applied Immunohistochemistry & Molecular Morphology | 2017

Virtual Double Staining: A Digital Approach to Immunohistochemical Quantification of Estrogen Receptor Protein in Breast Carcinoma Specimens

Nina Lykkegaard Andersen; Anja Høegh Brügmann; Giedrius Lelkaitis; Søren Nielsen; Michael Friis Lippert; Mogens Vyberg

Visual assessment of immunohistochemically detected estrogen receptor protein is prone to interobserver and intraobserver variation due to its subjective evaluation. The aim of this study was to validate a new image analysis system based on virtual double staining (VDS) by comparing visual and automated scorings of ER in tissue microarrays of breast carcinomas. Tissue microarrays were constructed of 112 consecutive resection specimens of breast carcinomas. Immunohistochemistry assays for ER and pancytokeratin was applied on separate serial sections. ER scoring was visually performed by 5 observers using the histoscore (H-score) method. The Visiopharm ER image analysis protocol (APP) software application using VDS technique was applied separating stromal cells from carcinoma and other epithelial cells based on the pancytokeratin reaction. Using color deconvolution, polynomial filters, and nuclear segmentation the APP determined the percentage of positive cells and their intensity, and calculated the resulting H-score. On the basis of 1% cutoff VDS was perfectly correlated with visual assessment (&kgr;=1). Using H-score, a very high agreement between VDS and visual ER assessment was seen (R2=0.950). Image analysis has the attributes to eliminate the shortcomings of visual ER evaluation by generating automated, reproducible, and objective results of ER assessment.


Acta Oncologica | 2017

Male breast cancer: a nation-wide population-based comparison with female breast cancer

Marianne D. Lautrup; Signe S. Thorup; Vibeke Jensen; Susanne Bokmand; Karen Haugaard; Inger Hoejris; Anne Marie Bak Jylling; Hjoerdis Joernsgaard; Giedrius Lelkaitis; Mette H. Oldenburg; Gro M. Qvamme; Katrine Soee; Peer Christiansen

Abstract Objective: Describe prognostic parameters of Danish male breast cancer patients (MBCP) diagnosed from 1980–2009. Determine all-cause mortality compared to the general male population and analyze survival/mortality compared with Danish female breast cancer patients (FBCP) in the same period. Material and methods: The MBCP cohort was defined from three national registers. Data was extracted from medical journals. Data for FBCP is from the DBCG database. Overall survival (OS) was quantified by Kaplan–Meier estimates. Standardized mortality ratios (SMRs) were calculated based on mortality rate among patients relative to the mortality rate in the general population. The association between SMR and risk factors were analyzed in univariate and multivariable Poisson regression models. Separate models for each gender were used for the analyses. Results: We found a marked difference in OS for the two genders. For the total population of MBCP, 5- and 10-year survivals were 55.1% and 31.7%, respectively. For FBCP, the corresponding figures were 76.8% and 59.3%. Median age at diagnosis for FBCP was 61 years and 70 years for MBCP. By applying SMR, the difference in mortality between genders equalized and showed pronounced age-dependency. For males <40 years, SMR was 9.43 and for females 19.56 compared to SMR for males 80 + years (0.95) and females 80 + years (0.89). During the period 1980–2009, the risk of dying gradually decreased for FBCP (p < .0001). The risk 1980–1984 was 35% higher than 2005–2009 (RR 1.35). Although the risk of dying for MBCP was also lowest in 2005–2009, there was no clear tendency (p = .1439). The risk was highest in 1990–1994 (RR =2.48). Conclusion: We found better OS for FBCP than for MBCP. But SMR showed similar mortality rate for the two genders, except for very young FBCP, who had higher SMR. Furthermore, significantly improved survival over time for FBCP was observed, with no clear tendency for MBCP.


OMICS journal of radiology | 2013

False-Negative 99mTc Medi-MIBI Parathyroid Scintigraphies: A Report onthe Possible Role of Diagnostic Two-Phase Single-Acquisition CT

Pia Afzelius; Iyer; Giedrius Lelkaitis; Søren Dammand Henriksen

Introduction: Dual-phase 99mTc-Medi-MIBI parathyroid scintigraphy is often used for preoperative localization of primary parathyroid adenomas. The overall accuracy has been reasonably high; however, some false-negative cases occasionally occur. Two such cases are presented, and the advantages of adding two-phased single-acquisition diagnostic CT to guide the surgeon are demonstrated. Case presentations: A 54-year old male was admitted due to persistent elevated parathyroid hormone and calcium concentrations in the blood despite medical treatment consistent with primary hyperparathyroidism. A dualphase parathyroid scintigraphy performed 6 months earlier in another hospital was unable to confirm the diagnosis. There was no change over time in levels of parathyroid hormone and calcium in the blood. In the second case, a 46- year old woman was examined due to the same symptoms and findings; 18 months earlier she also had no retention of tracer on late images. In this case, the patient also had had a CT performed, which showed morphological signs of a parathyroid adenoma. We therefore planned dual-phase parathyroid scintigraphy with single-photon emission computed tomography/computed tomography (SPECT/CT) in the early phase. The low-dose CT was unable to confirm the impression of slight amounts of tracer uptake and retention at the lower right thyroid pole in both cases. Diagnostic in both cases, but still with a low dose, the CT revealed a parathyroid adenoma situated in a common parathyroid location at the lower pole of the right thyroid lobe, where activity retention was seen in late images. The surgeon was able to perform minimally invasive neck surgery based on accurate anatomical localization of the adenoma. Conclusion: This case report highlights the potential of two-phase single-acquisition CT as a useful tool in exact localization of parathyroid adenoma for guiding the surgeon in minimally invasive surgery.

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Maj-Lis Møller Talman

Copenhagen University Hospital

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Birgitte Charabi

Copenhagen University Hospital

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