Test structure in some pioneer multichambered Paleozoic foraminifera.

Foraminiferal wall microstructures, consistent with the molecular-based high-rank classification, are critical to understanding foraminiferal evolution and advanced taxonomic relationships. Although test structures are well documented for recent, Cenozoic, and some Mesozoic foraminifera, the diagnostic characteristics of Paleozoic taxa are largely unexplored. The majority of calcareous Paleozoic foraminifera have been assigned to the Fusulinata based on questionable homogeneously "microgranular" test wall microstructures, which have never been sufficiently documented for most taxa. We investigated the test structures of exceptionally well-preserved Devonian (Eifelian) Semitextularia thomasi, representing the first calcareous true multichambered (serial) foraminifera, and compared this species with a large fusiform Permian representative of "true" fusulinids (Neoschwagerinidae). The tests of Semitextularia thomasi display lamellar structures that are not observed in any other fossil or recent foraminiferal group. The Paleozoic foraminifera, traditionally referred to one taxon (the class Fusulinata), possess at least three contrasting test wall microstructures, representing separate high-rank taxonomic groups. Fusulinata is most likely a highly polyphyletic group that is in need of taxonomic revision. The term Fusulinata, defined as including all Paleozoic calcareous forms except Miliolida and Lagenata, is not phylogenetically meaningful and should no longer be used or should be restricted to true complex fusulinids with microgranular test structures, which appeared in the Carboniferous.

Quantum State Reduction by Matter-Phase-Related Measurements in Optical Lattices.

A many-body atomic system coupled to quantized light is subject to weak measurement. Instead of coupling light to the on-site density, we consider the quantum backaction due to the measurement of matter-phase-related variables such as global phase coherence. We show how this unconventional approach opens up new opportunities to affect system evolution. We demonstrate how this can lead to a new class of final states different from those possible with dissipative state preparation or conventional projective measurements. These states are characterised by a combination of Hamiltonian and measurement properties thus extending the measurement postulate for the case of strong competition with the system's own evolution.

Surgical injury-induced early neocortical microvascular changes and characteristics of the cells populating the peri-lesion zone.

Adult mammalian brain contains a number of specialized neurovascular structures termed "niches" that act as sources of neuronal cells throughout the individual's life. Some of the niches generate neurons to satisfy the need for 'replacement' neurons within the same or closely located brain structures, whereas the other can provide such cells for more distant destinations in the brain. A common characteristic of known neurovascular niches is the presence of a complex 3-dimensional network of basal lamina processes, called fractones. It apparently plays a major role in communication between the various niche-populating cell types as well as in niche activity and output. We hypothesized that similar niches may form ad hoc after a mechanical brain trauma, and tested this possibility in a rat model of surgical brain injury. Four days after removing a small fragment of sensorimotor cortex, the peri-wound region showed numerous symptoms of active repair and remodeling of brain parenchyma, including the presence of multiple cell types of immature phenotypes. The latter, as shown by a variety of light and electron microscopy techniques, included endothelial cell precursors as well as nestin-positive immature neural cells of astrocytic or non-glial characteristics. However, there was no evidence of in situ neurogenesis or a considerable migration of cells from SVZ. The centers of the said repair processes were capillary blood vessels connected with basal lamina-formed fractones. These results indicate that surgical brain trauma causes the formation of a vascular niche with no apparent neurogenic potential.

Functional Assessment of Synoptic Pathology Reporting for Ovarian Cancer.

BACKGROUND: Ovarian cancer has one of the highest death/incidence rates and is commonly diagnosed at an advanced stage. In the recent WHO classification, new histotypes were classified which respond differently to chemotherapy. The e-standardized synoptic cancer pathology reports offer the clinicians essential and reliable information. The aim of our project was to develop an e-template for the standardized synoptic pathology reporting of ovarian carcinoma [based on the checklist of the College of American Pathologists (CAP) and the recent WHO/FIGO classification] to introduce a uniform and improved quality of cancer pathology reports. A functional and qualitative evaluation of the synoptic reporting was performed. METHODS: An indispensable module for e-synoptic reporting was developed and integrated into the Hospital Information System (HIS). The electronic pathology system used a standardized structure with drop-down lists of defined elements to ensure completeness and consistency of reporting practices with the required guidelines. All ovarian cancer pathology reports (partial and final) with the corresponding glass slides selected from a 1-year current workflow were revised for the standard structured reports, and 42 tumors [13 borderline tumors and 29 carcinomas (mainly serous)] were included in the study. RESULTS: Analysis of the reports for completeness against the CAP checklist standard showed a lack of pTNM staging in 80% of the partial or final unstructured reports; ICD-O coding was missing in 83%. Much less frequently missed or unstated data were: ovarian capsule infiltration, angioinvasion and implant evaluation. The e-records of ovarian tumors were supplemented with digital macro- and micro-images and whole-slide images. CONCLUSIONS: The e-module developed for synoptic ovarian cancer pathology reporting was easily incorporated into HIS.CGM CliniNet and facilitated comprehensive reporting; it also provided open access to the database for concerned recipients. The e-synoptic pathology reports appeared more accurate, clear and conclusive than traditional narrative reports. Standardizing structured reporting and electronic tools allows open access and downstream utilization of pathology data for clinicians and tumor registries.

Immune response in breast cancer brain metastases and their microenvironment: the role of the PD-1/PD-L axis.

BACKGROUND: A better understanding of immune response in breast cancer brain metastases (BCBM) may prompt new preventive and therapeutic strategies. METHODS: Immunohistochemical expression of stromal tumor-infiltrating lymphocytes (TILs: CD4, CD8, CTLA4), macrophage/microglial cells (CD68), programmed cell death protein 1 receptor (PD-1), programmed cell death protein 1 receptor ligand (PD-L)1, PD-L2 and glial fibrillary acid protein was assessed in 84 BCBM and their microenvironment. RESULTS: Median survival after BCBM excision was 18.3 months (range 0-99). Median number of CD4+, CD8+ TILs and CD68+ was 49, 69 and 76 per 1 mm(2), respectively. PD-L1 and PD-L2 expression in BCBM was present in 53 % and 36 % of cases, and was not related to BCBM phenotype. PD-1 expression on TILs correlated positively with CD4+ and CD8+ TILs (r = 0.26 and 0.33), and so did CD68+ (r = 0.23 and 0.27, respectively). In the multivariate analysis, survival after BCBM excision positively correlated with PD-1 expression on TILs (hazard ratio (HR) = 0.3, P = 0.003), CD68+ infiltration (HR = 0.2, P < 0.001), brain radiotherapy (HR = 0.1, P < 0.001), endocrine therapy (HR = 0.1, P < 0.001), and negatively with hormone-receptor-negative/human epidermal growth factor receptor 2 (HER2)-positive phenotype of primary tumor (HR = 2.6, P = 0.01), HER2 expression in BCBM (HR = 4.9, P = 0.01). CONCLUSIONS: PD-L1 and PD-L2 expression is a common occurrence in BCBM, irrespective of primary tumor and BCBM phenotype. Favorable prognostic impact of PD-1 expression on TILs suggests a beneficial effect of preexisting immunity and implies a potential therapeutic role of immune checkpoint inhibitors in BCBM.

Experimental modeling of pulmonary barotrauma.

The main causes of pulmonary barotrauma include loss of consciousness or panic attack of a diver and emergence from underwater with a constricted glottis. However, numerous publications and our observations indicate that the majority of fully symptomatic cases of pulmonary barotrauma develop without any evident errors in the ascending technique. Therefore, an attempt was made to examine such cases using the experimental model of pulmonary barotrauma designed by the authors. The experiment was conducted on 32 rabbits divided into three groups: Group C--not subjected to any treatment; Group E--with induced pulmonary barotrauma; and Group CT--subjected only to compression followed by quick decompression. In Groups E and CT, the same morphological markers of pulmonary barotrauma were detected in the lungs, although their severity varied. Morphological markers of pulmonary barotrauma were observed both in the group where the tube was not ob-structed (E) and in animals exposed only to rapid decompression (CT)

Computerized System for Quantitative Assessment of Atherosclerotic Plaques in the Femoral and Iliac Arteries Visualized by Multislice Computed Tomography.

OBJECTIVE: The investigation is aimed at the development of a semiautomatic method of examining the femoral and iliac arteries, and quantifying atherosclerotic plaques visible in the multislice computed tomography images. METHODS: We have utilized the advanced morphology and segmentation methods for processing of a series of the images. In particular, a novel sorted pixel intensity approach to segment the artery into the lumen/plaque regions has been used, and effectively combined with the Gaussian mixture modeling to increase the accuracy of the segmentation. RESULTS: Our numerical results are compared with those obtained manually by two experts. Statistics relevant to the progression of atherosclerosis have also been suggested. Results of the semiautomatic tracking of the femoral and iliac arteries and of the quantitative evaluation of atherosclerotic alterations therein have been shown to correspond well with the expert's results. CONCLUSION: The developed system is likely to be valuable tool for supporting the quantitative evaluation of atherosclerotic changes in arteries. SIGNIFICANCE: In its present form the system can be used for planning surgical treatment and/or predicting the course of the atherosclerotic alterations.

Hepatoprotective effect of nitric oxide in experimental model of acute hepatic failure.

AIM: To evaluate the effect of nitric oxide (NO) on the development and degree of liver failure in an animal model of acute hepatic failure (AHF). METHODS: An experimental rat model of galactosamine-induced AHF was used. An inhibitor of NO synthase, nitroarginine methyl ester, or an NO donor, arginine, were administered at various doses prior to or after the induction of AHF. RESULTS: All tested groups developed AHF. Following inhibition of the endogenous NO pathway, most liver parameters improved, regardless of the inhibitor dose before the induction of liver damage, and depending on the inhibitor dose after liver damage. Prophylactic administration of the inhibitor was more effective in improving liver function parameters than administration of the inhibitor after liver damage. An attempt to activate the endogenous NO pathway prior to the induction of liver damage did not change the observed liver function parameters. Stimulation of the endogenous NO pathway after liver damage, regardless of the NO donor dose used, improved most liver function parameters. CONCLUSION: The endogenous NO pathway plays an important role in the development of experimental galactosamine-induced AHF.

Computer approach to recognition of Fuhrman grade of cells in clear-cell renal cell carcinoma.

OBJECTIVE: To present a computerized system for recognition of Fuhrman grade of cells in clear-cell renal cell carcinoma on the basis of microscopic images of the neoplasm cells in application of hematoxylin and eosin staining. STUDY DESIGN: The applied methods use combined gradient and mathematical morphology to obtain nuclei and classifiers in the form of support vector machine to estimate their Fuhrman grade. The starting point is a microscopic kidney image, which is subject to the advanced methods of preprocessing, leading finally to estimation of Fuhrman grade of cells and the whole analyzed image. RESULTS: The results of the numerical experiments have shown that the proposed nuclei descriptors based on different principles of generation are well connected with the Fuhrman grade. These descriptors have been used as the diagnostic features forming the inputs to the classifier, which performs the final recognition of the cells. The average discrepancy rate between the score of our system and the human expert results, estimated on the basis of over 3,000 nuclei, is below 10%. CONCLUSION: The obtained results have shown that the system is able to recognize 4 Fuhrman grades of the cells with high statistical accuracy and agreement with different expert scores. This result gives a good perspective to apply the system for supporting and accelerating the research of kidney cancer.

Survivin expression as a prognostic factor in patients with epithelial ovarian cancer or primary peritoneal cancer treated with neoadjuvant chemotherapy.

BACKGROUND: The aim of this study was to evaluate association of expression of survivin and p53 with the effects of neoadjuvant chemotherapy (NAC) in patients with advanced ovarian cancer (AOC). METHODS: We retrospectively evaluated 60 consecutive patients with AOC (International Federation of Gynecology and Obstetrics stage IIIC-IV) treated with NAC. The expression of p53 and survivin was assessed immunohistochemically. The median of expression total score survivin equals 2 was adopted to dichotomize the group. The positive and negative expression of p53 was used to dichotomize the group. RESULTS: The expression of survivin in tumor tissue taken before and after NAC was a significant difference in the percentage of stained nuclei (P = 0.0002), the intensity of staining (P = 0.0003), and total score (P = 0.0001). There was a significant difference in p53 expression in tumor tissue before and after NAC in the percentage of stained nuclei (P = 0.0424). Survivin expression, in contrast to p53 expression, was a prognostic factor in patients with AOC treated with NAC (P = 0.0484). The expression of survivin and p53 was not a predictive factor. Independent adverse predictor factors were as follows: lack of optimal interval debulking surgery and the lack of an objective response (the respective hazard ratio was 3.93 [95% confidence interval, 2.07-7.46; P < 0.0001] and 2.36 [95% confidence interval,1.25-4.47; P = 0.0080]). The suboptimal range of interval debulking surgery, resistance to platinum, and the lack of paclitaxel in the NAC were adverse prognostic factors (the respective hazard ratio was 2.61 [95% confidence interval, 1.17-5.83], 2.72 [95% confidence interval, 1.07-6.89], and 2.56 [95% confidence interval, 1.06-6.18]; P < 0.05]). CONCLUSIONS: High expression of survivin could be a prognostic factor in patients treated with NAC for AOC.

Morphological evaluation of the iliac and femoral arteries; possibilities and perspectives.

UNLABELLED: The study presented an approach to the morphometric image of atherosclerotic lesions of the final segment of the abdominal aorta, femoral and iliac arteries, considering possible endovascular intervention. The evaluation of these arteries is very important, because they are often used as a point of access for endovascular procedures performed on the peripheral arteries, or within the thoracic and abdominal aorta and its branches, as well as coronary arteries. The aim of the study was to determine morphometric measurements describing the atherosclerotic lesions, including the methodology of their surgical interpretation. MATERIAL AND METHODS: The study group comprised 128 tomograms of patients qualified for surgery. An algorithm based on the mathematical morphology was designed to track the vessels, starting from the division of the common femoral artery, and ending at the bifurcation of the abdominal aorta. We proposed a set of numerical measurements of the observed arterial changes. RESULTS AND CONCLUSIONS: We analysed 128 tomograms with a 94.5% efficiency, and with the assessment accuracy of the degree of lumen reduction (MAE--1.5%). We observed much higher measurement values of local tortuosity of the atherosclerotic arteries (0.3-1 radians), as compared to their anatomical course in a healthy subject (0-0.2 radians). The presented method can be a very accurate and useful tool in the numerical analysis of the lumen distribution of the arteries and atherosclerosis, dedicated to surgeons elaborating management strategies.

Wnt/ß-catenin pathway as a potential prognostic and predictive marker in patients with advanced ovarian cancer.

BACKGROUND: ß-catenin is the key protein in the WNT signalling pathway and it forms adherent junctions together with E-cadherin. In ovarian carcinoma, abnormal expression of ß-catenin, E-cadherin and WNT-1 was observed, but their prognostic and predictive role is unclear. The aim of this study was to clarify the prognostic and predictive role of E-cadherin, ß-catenin and WNT-1 in advanced epithelial ovarian carcinoma (AEOC). METHODS: The expression of E-cadherin, ß-catenin and WNT-1 was determined by immunohistochemistry in AEOC. The correlation between expression of these proteins and progression-free survival (PFS) and overall survival (OS) was evaluated. Statistical analyses included Kaplan-Meier estimation, log-rank test, Spearman correlation and Cox proportional-hazards model. RESULTS: In ovarian cancer, intense expression of E-cadherin, ß-catenin and WNT-1 was found. In multivariate analysis, strong membrane ß-catenin expression was an independent unfavourable predictor for PFS (HR 2.19, 95% CI 1.09-4.39; p = 0.028), while in univariate analysis, strong membrane ß-catenin expression was a prognostic factor for OS in patients with AOC (p = 0.039). In multivariate analysis, only resistance to first-line chemotherapy was an adverse independent prognostic factor for OS (HR 16.84; 95% CI 5.07-55.98; p < 0.0001). Additionally, strong membranous ß-catenin expression was associated with resistance to platinum-based chemotherapy (p = 0.027). CONCLUSIONS: These findings support that WNT/ß-catenin pathway and E-cadherin are important factors in advanced epithelial ovarian cancer.

A case of a large solitary fibrous tumour of the uterine cervix.

BACKGROUND: Solitary fibrous tumour of the uterine cervix is an extremely rare phenomenon. We present a case of the largest cervical tumour of this type in this anatomical location reported so far. CASE PRESENTATION: A 45-year old white female presented with abdominal pain, abnormal uterine bleedings and a 15 cm mass of the uterine cervix/left parametrium. Histological examination with immunohistochemistry of the tumour biopsy revealed diagnosis of solitary fibrous tumour. The patient underwent radical abdominal hysterectomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy. No recurrence has been observed for 8 months of follow-up. CONCLUSIONS: Solitary fibrous tumour can be occasionally found in patients with large cervical/parametrial masses. Immunohistochemistry was helpful in diagnosis and surgery was feasible and effective in treatment of our case of a large solitary fibrous tumour of the cervix.

Nucleolus detection in the Fuhrman grading system for application in CCRC.

The paper presents a method for nucleolus detection in images of nuclei in clear-cell renal carcinoma (CCRC). The method is based on the similarity of the nuclei image and the two-dimensional paraboloidal window function. The results of numerical experiments performed on almost 2600 images of CCRC nuclei have confirmed the good accuracy of the method. The developed algorithm will be used to accelerate further research in computer-assisted diagnosis of CCRC.

The influence of the microscope lamp filament colour temperature on the process of digital images of histological slides acquisition standardization.

BACKGROUND: The aim of this study is to compare the digital images of the tissue biopsy captured with optical microscope using bright field technique under various light conditions. The range of colour's variation in immunohistochemically stained with 3,3'-Diaminobenzidine and Haematoxylin tissue samples is immense and coming from various sources. One of them is inadequate setting of camera's white balance to microscope's light colour temperature. Although this type of error can be easily handled during the stage of image acquisition, it can be eliminated with use of colour adjustment algorithms. The examination of the dependence of colour variation from microscope's light temperature and settings of the camera is done as an introductory research to the process of automatic colour standardization. METHODS: Six fields of view with empty space among the tissue samples have been selected for analysis. Each field of view has been acquired 225 times with various microscope light temperature and camera white balance settings. The fourteen randomly chosen images have been corrected and compared, with the reference image, by the following methods: Mean Square Error, Structural SIMilarity and visual assessment of viewer. RESULTS: For two types of backgrounds and two types of objects, the statistical image descriptors: range, median, mean and its standard deviation of chromaticity on a and b channels from CIELab colour space, and luminance L, and local colour variability for objects' specific area have been calculated. The results have been averaged for 6 images acquired in the same light conditions and camera settings for each sample. CONCLUSIONS: The analysis of the results leads to the following conclusions: (1) the images collected with white balance setting adjusted to light colour temperature clusters in certain area of chromatic space, (2) the process of white balance correction for images collected with white balance camera settings not matched to the light temperature moves image descriptors into proper chromatic space but simultaneously the value of luminance changes. So the process of the image unification in a sense of colour fidelity can be solved in separate introductory stage before the automatic image analysis.

Morphological evidence of the beneficial role of immune system cells in a rat model of surgical brain injury.

The blood-brain barrier prevents infiltration of peripheral immunocompetent cells into the CNS under physiological conditions. Following brain trauma there is reported a rapid and massive immunological response. Our earlier data indicated that surgical brain injury causes breaking of brain parenchyma integrity and results in cell changes and death, astrogliosis and disruption of blood vessels. The aim of the present studies was to investigate and characterize immunocompetent cells entering brain damaged parenchyma in the early period following the injury in a rat model of surgical damage. In the investigations we used light and electron microscopy techniques. Four days following the lesion many monocytes and macrophages were detected in the injured parenchyma. We also found many activated microglial cells with phagosomes within the cytoplasm. The phagocytes digest the cellular debris and clean up the parenchyma. The data suggest the beneficial role of immunocompetent cells following surgical injury.

Overexpression of epidermal growth factor receptor as a prognostic factor in colorectal cancer on the basis of the Allred scoring system.

BACKGROUND: Overexpression of epidermal growth factor receptor (EGFR) is found in many types of neoplasms. The aim of the study was to evaluate EGFR expression in colorectal cancer (CRC) specimens and to determine whether EGFR expression correlates with clinicopathological data and overall survival. PATIENTS AND METHODS: Tissue specimens from 181 consecutive CRC patients treated at the Military Institute of Medicine in 2006-2010 were collected and examined for EGFR expression, by immunohistochemistry staining. The staining intensity and percentage of cells with membranous EGFR expression were scored and then grouped according to the parameters of the Allred Scoring system. Cutoff values were subjected to further statistical analysis. Univariate tests and a multivariate Cox proportional hazards model were used in data analysis. RESULTS: EGFR was overexpressed in 96 of 181 CRC specimens (53%). EGFR expression was not correlated with other clinicopathological variables. On univariate analysis, overexpression of EGFR, determined by PS (percentage score) (>3) and total score (sum of PS and intensity score) (>4), was associated with poor overall survival. On multivariate analysis, EGFR overexpression (PS > 3) was an independent adverse prognostic factor (hazard ratio [HR] 1.62; 95% confidence interval [CI]: 1.03-2.53). Elevated carcinoembryonic antigen (CEA) serum concentration before treatment, performance status (Word Health Organization [WHO]-2), and tumor localized in colon and liver metastases were also independent unfavorable prognostic factors. CONCLUSION: EGFR overexpression (PS > 3) in a CRC patient population was an independent adverse prognostic factor. Implementation of the Allred Scoring system criteria into clinical practice might facilitate treatment decisions in CRC patients.

Immunohistochemical evaluation of human epidermal growth factor receptor 2 and estrogen and progesterone receptors in invasive breast cancer in women.

INTRODUCTION: Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) expression are crucial in the biology of breast carcinoma. HER-2/neu gene is amplified and overexpressed in 15-30% of invasive breast cancers. HER-2-positive breast cancers have worse prognosis than HER-2 negative tumors and possess distinctive clinical features. The aim of this study was to assess the expression of HER2 in cancer tissue of patients with invasive breast cancer in correlation with tumor type, histological grade, tumor size, lymph node status, and expression of estrogen receptor and progesterone receptor. MATERIAL AND METHODS: Formalin-fixed, paraffin-embedded tissues from 40 patients with invasive HER-2-positive breast cancer and from 191 patients with HER-2-negative breast cancer were used in this study. HER2 expression was determined using the test HerceptTest™ DAKO. RESULTS: Among 231 cases of breast cancer, 18 invasive lobular carcinomas and 213 invasive ductal carcinomas were diagnosed. Sixty percent of HER-2-positive breast cancers were ER-positive compared with 77% in the HER-2-negative group (p = 0.002). The expression of PR was observed in 43% of HER-2-positive breast cancers and in 72% of HER2-negative tumors (p = 0.003). Excessive expression of HER2 protein was detected in 60% of patients positive for estrogen receptors, which may worsen prognosis in these patients. CONCLUSIONS: Determination of HER2 overexpression in breast cancer patients, allows for a determination of a group of patients with a worse prognosis.

Skull base secretory meningioma. Value of histological and immunohistochemical findings for peritumoral brain edema formation.

Meningiomas are very common neurosurgical problem. Their histological appearance, different size and localization, adherence to vital neural and vascular structures or extensive peritumoral brain edema (PTBE), especially in deep seated tumors, may lead to severe, life-threatening complications. We report a case of tuberculum sellae meningioma (TSM). A 48-year old female presented with 7-month history of blurred vision and progressive visual impairment. Intracranial tumor was confirmed by magnetic resonance imaging (MRI). After ophtalmological and endocrinological evaluation, the patient underwent surgical removal of the tumor. She immediately recovered from her visual disturbances and no tumor recurrences were seen during follow-up. Pathological diagnosis showed a meningioma of the secretory subtype (MS). We discuss the role of immunohistochemical staining in the diagnosis and the role of different factors in the PTBE formation. Selection of surgical route to the TSM is discussed, as well. Review of the literature is presented.

Tau protein as a potential predictive marker in epithelial ovarian cancer patients treated with paclitaxel/platinum first-line chemotherapy.

BACKGROUND: The aim of the study was to evaluate predictive and prognostic significance of microtubule-associated protein Tau in epithelial ovarian cancer (EOC) patients treated with paclitaxel and platinum-based chemotherapy. METHODS: 74 patients with EOC (stage I-IV) who underwent cytoreductive surgery followed by standard paclitaxel/platinum chemotherapy were included in the retrospective analysis. Their formalin-fixed, paraffin-embedded tissue specimens were immunohistochemically stained for Tau protein, using semi-quantitative DAKO test. Tau expression was acknowledged as negative (0 and 1+) or positive (2+ and 3+). The correlation between Tau expression, progression free survival (PFS) and overall survival (OS) was evaluated. Statistical analysis included Kaplan-Meyer estimator, long rank test, Mann Whitney test and Cox proportional hazards model. RESULTS: 25.7% (19/74) and 74.3% (55/74) of the patients were classified as Tau-negative and Tau-positive, respectively. Median PFS was 28.7 months for Tau-negative group and 15.9 months for Tau-positive group (p = 0.0355). In the univariate analysis 3-year OS in Tau-negative and Tau-positive groups was 80.2% and 52.4%, respectively (p = 0.0198). Low expression of protein Tau was associated with better OS, whereas an advanced stage at diagnosis, suboptimal surgery, serous histological type and resistance to first line chemotherapy were each correlated with worse OS (p <0,05). In multivariate analysis only resistance to first line chemotherapy remained significant (HR 22.59; 95% CI, 8.71-58.55; p <0.0001). CONCLUSIONS: Negative tau protein seems to be both good prognostic factor and a predictor of response to paclitaxel/platinum-based chemotherapy in EOC patients.