Symmetric random walks on Homeo+(R)

We study symmetric random walks on finitely generated groups of orientation-preserving homeomorphisms of the real line. We establish an oscillation property for the induced Markov chain on the line that implies a weak form of recurrence. Except for a few special cases, which can be treated separately, we prove a property of "global stability at a finite distance": roughly speaking, there exists a compact interval such that any two trajectories get closer and closer whenever one of them returns to the compact interval. The probabilistic techniques employed here lead to interesting results for the study of group actions on the line. For instance, we show that under a suitable change of the coordinates, the drift of every point becomes zero provided that the action is minimal. As a byproduct, we recover the fact that every finitely generated group of homeomorphisms of the real line is topologically conjugate to a group of (globally) Lipschitz homeomorphisms. Moreover, we show that such a conjugacy may be chosen in such a way that the displacement of each element is uniformly bounded

Adenomatoid Tumor of Testis

Adenomatoid tumors are responsible for 30% of all paratesticular masses. These are usually asymptomatic, slow growing masses. They are benign tumors comprising of cords and tubules of cuboidal to columnar cells with vacuolated cytoplasm and fibrous stroma. They are considered to be of mesothelial origin supported by histochemical studies and genetic analysis of Wilms tumor 1 gene expression. Excision biopsy is both diagnostic and therapeutic procedure. The main clinical consideration is accurate diagnosis preventing unnecessary orchiectomy. Diagnostic studies include serum tumor markers (negative alpha fetoprotein, beta HCG, LDH) ultrasonography (hypoechoic and homogenous appearance) and frozen section

Atypical adenomatous hyperplasia (adenosis) of the prostate: a case report with review of the literature

A 62-year-old male presented with symptoms of urinary obstruction and elevated serum prostate-specific antigen level of 3.61 ng/mL. Prostate needle biopsies showed benign prostatic tissue with a focus of crowded glands with minimal cytological atypia, fairly well-circumscribed with infiltrative appearance of glands at the edges. This focus had both small and larger glands with similar histological features. This focus was strongly positive for alpha-methylacyl-coenzyme A-racemase (AMACR), but showed scattered patchy staining with basal cell markers (p63 and CK903/34βE12). Hence, the final histologic diagnosis was benign prostatic tissue with a focus of florid adenosis. Two subsequent follow-up prostate needle biopsies performed six and 12 months later both showed benign prostatic tissue with atrophic changes. This case highlights the utility of these three immunostains (AMACR, p63 and CK903/34βE12) in the accurate diagnosis of adenosis of the prostate on needle biopsy, and avoiding its misinterpretation as prostate adenocarcinoma

Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Kidney: Two Unusual Presentations of a Rare Tumor

Only few cases of primary renal Ewing's sarcoma have been reported in the literature to date. We present here two cases of renal ES/PNET with an uncanny presentation. The first case was discovered after the patient presented clinically with irradiating flank pain, mimicking the pain related with kidney stones. The second case had clinical presentation of pulmonary thromboembolism after the patient was involved in an automobilist accident. The tumors were mainly composed of small blue cells which by immunohistochemical were positive for neural markers, and FISH revealed the translocation 22q12 for the EWSR1 gene. The diagnosis of renal primitive neuroectodermal tumor/EWING tumor is very rare and usually involves several different diagnostic techniques. The differential diagnosis is usually broad with frequent overlapping features between the entities. The cases presented in this paper illustrated the difficulties with which routine anatomical pathologist is faced when dealing with rare renal poorly differentiated neoplasm in adults

Malignant perivascular epithelioid cell tumor (PEComa) of the uterus with late renal and pulmonary metastases: a case report with review of the literature

<p>Abstract</p> <p>Background</p> <p>Perivascular epithelioid cell tumor (PEComa), other than angiomyolipoma (AML), clear cell sugar tumor (CCST), and lymphangioleiomyomatosis (LAM), is a very rare mesenchymal tumor with an unpredictable natural history. The uterus is the most prevalent reported site of involvement of PEComa-not otherwise specified (PEComa-NOS). To the best of our knowledge, about 100 PEComa-NOS have been reported in the English Language medical literature, of which 38 were uterine PEComa-NOS. These reported cases of uterine PEComa-NOS have usually shown clinically benign behavior, but 13 tumors, three of them associated with tuberous sclerosis complex (TSC), exhibited local aggressive behavior and four of them showed distant metastases.</p> <p>Case presentation</p> <p>We report the case of a 59-year-old woman, who presented with renal and pulmonary lesions seven years after the initial diagnosis of uterine leiomyosarcoma. Left nephrectomy and right middle lobe wedge resection were performed. Histological and immunohistochemical analysis of the renal and pulmonary lesions, in addition to retrospective re-evaluation of the previous uterine tumor, led to the final diagnosis of malignant uterine PEComa with late renal and pulmonary metastases. All three lesions had the typical histological appearance of PEComa-NOS showing a biphasic growth pattern with continuous transition between spindle cells and epithelioid cells, often arranged around vascular spaces. Immunohistochemically, the tumor cells of both phenotypes in all three lesions stained for melanocytic (HMB-45 and Melan-A/MART-1) and myoid (desmin, smooth muscle actin, and muscle-specific actin/all muscle actin/HHF-35) markers.</p> <p>Conclusion</p> <p>The findings indicate that despite the small number of reported cases, PEComas-NOS should be considered tumors of uncertain malignant potential, and metastases to other organs might become evident even several years after the primary diagnosis.</p

Diagnostic utility of p501s (prostein) in comparison to prostate specific antigen (PSA) for the detection of metastatic prostatic adenocarcinoma

<p>Abstract</p> <p>Background</p> <p>Immunohistochemical detection of prostate specific antigen (PSA) is widely used to identify metastatic prostatic adenocarcinoma. However, PSA may not be expressed in some poorly differentiated prostatic carcinomas and its immunoreactivity has been found in some non-prostatic tissues. P501s (prostein) is a prostate-specific marker that is expressed in the cytoplasm of benign and malignant prostatic glandular cells. It has not been detected in any other normal or malignant tissues. The purpose of this study was to evaluate the expression of P501s in metastatic prostatic adenocarcinoma and compare its expression with PSA.</p> <p>Methods</p> <p>Immunohistochemical stains with anti-P501s antibodies were performed on 5-micron sections of tissue microarray (TMA) specimens. The TMA is constructed with normal donor prostates (NDP), prostatic adenocarcinoma (PRCA), non-neoplastic prostatic tissues adjacent to malignant glands (NAT), benign prostatic hyperplasia (BPH), high-grade prostatic neoplasia (PIN), metastatic adenocarcinoma to lymph nodes (MLN), metastatic adenocarcinoma to other sites (MC), and samples of benign testis, colon, adrenal and kidney. The two groups of metastatic lesions were also subjected to stains with antibodies to PSA. A composite score (ranging from 0 to 3) was assigned to score intensity of staining.</p> <p>Results</p> <p>Granular staining pattern of p501s was seen in all benign glands (score = 1.77 – 2.1) and malignant acini (score = 1.52) at the apical aspect of cytoplasm, predominantly adjacent to the nuclei. No staining was observed in controls including testis, colon, adrenal and kidney. The MLN group received a score of 1.0, with 10% of cases negative for p501s. The MC cases had a score of 0.64, with 16.7% of case showing loss of p501s expression. Although the metastatic lesions demonstrated similar rate of negative expression with PSA antibody, only 2 MC cases (3.3%) showed simultaneous negative stains for both P501S and PSA.</p> <p>Conclusion</p> <p>P501s is an organ specific marker for benign and malignant prostatic epithelial cells. Its characteristic cytoplasmic stain pattern provides an additional valuable immunomarker for detection of metastatic prostatic malignancy, even though the intensity of its expression is reduced, as in the case with PSA. Simultaneous stains with P501S and PSA will greatly improve the detection rate and identify a significant majority of the metastases.</p

Utility and applications of synoptic reporting in pathology

Background: Synoptic reports in routine pathology practice provide composite documents that include information from morphology and molecular technologies. It is clear and accurate structured information and developed by incorporating standardized data elements in the form of checklist for pathology reporting. This facilitates pathologists to document their findings and ultimately improve the overall quality of pathology reports.\ud \ud Objectives: The goal of this review article is to discuss (1) the importance of synoptic reporting in pathology, (2) utility and applications, (3) its impact on pathology reporting and patient care, and (4) the challenges and barriers of implementing synoptic reporting. Pertinent literature will also be reviewed.\ud \ud Design: The synoptic reporting system provides a complete set of data elements in the form of synoptic templates or “worksheets” for pathology tumor reporting based on the World Health Organization (WHO) Classification and the College of American Pathologists (CAP) Cancer Checklists. These standards provide most updated and supplemented classification scheme, specimen details, and staging as well as prognostic information. Data from synoptic reporting tool can be imported to a relational database where they are organized and efficiently searched and retrieved. Since search and retrieval are streamlined, synoptic databases enhance basic ­science, clinical, and translational cancer research.\ud \ud Conclusion: Synoptic reporting facilitates a standard based structured method for entering the diagnostic and prognostic information in accurate and consistent fashion for a particular ­pathology specimen, thus reducing transcription services, specimen turnaround time, and typographical and transcription errors. The structured data can be imported into the Laboratory Information Service (LIS) database, which facilitates swift data access and improved communication for cancer management. Finally, these synoptic templates act as a robust medium of high-quality data from the various biospecimens, which can be shared across multiple on-going research projects to enhance basic and translational research

Three-loop Phi-derivable Approximation in QED

In this paper we examine Phi-derivable approximations in QED. General theorems tell us that the gauge dependence of the n-loop Phi-derivable approximation shows up at order g^(2n) where g is the coupling constant. We consider the gauge dependence of the two-loop Phi-derivable approximation to the Debye mass and show that it is of order e^4 as expected. We solve the three-loop Phi-derivable approximation in QED by expanding sum-integrals in powers of e^2 and m/T, where m is the Debye mass which satisfies a variational gap equation. The results for the pressure and the Debye mass are accurate to order e^5.Comment: 10 pages, 5 figures. v2: typos corrected and references adde

Tubular adenoma with high-grade dysplasia in the ileal segment 34 years after augmentation ileocystoplasty: report of a first case

Neoplasms of the urinary bladder following augmentation ileocystoplasty are rare. We present the case of a 39-year-old male with a tubular adenoma with high-grade dysplasia in the ileal segment 34 years after augmentation ileocystoplasty to enlarge a post-chemoradiation-induced shrunken bladder. He presented with gross hematuria. Cystoscopy revealed a papillary tumor at the site of ileovesical anastomosis, and transurethral resection was performed. Histologic examination revealed a tubular adenoma with high-grade dysplasia. There are only two previous reports of tubulovillous adenoma in ileal segment after ileocystoplasty, both without high-grade dysplasia. Our observation supports the hypothesis that an ileal neobladder may undergo all the morphologic and molecular changes observed in the development of gastrointestinal adenocarcinoma. Therefore, patients who had an ileal neobladder created should be closely followed