44 research outputs found
Convergence and Divergence of the Solutions of a Neutral Difference Equation
We investigate the asymptotic behavior of the solutions of a neutral type difference equation of the form Δ[()+(())]+()(())=0, where () is a general retarded argument, () is a general deviated argument (retarded or advanced), ∈ℝ, (())≥0 is a sequence of positive real numbers such that ()≥, ∈ℝ+, and Δ denotes the forward difference operator Δ()=(+1)−(). Also, we examine the asymptotic behavior of the solutions in case they are
continuous and differentiable with respect to
Subcutaneous tumor seeding after biopsy in gliomatosis cerebri
We observed a patient with subcutaneous seeding from gliomatosis cerebri with a low-grade histopathology. A 33-year-old woman with neurofibromatosis type 1 presented with progressive headache, diplopia, dysphagia, and a rightward instability. On neurological examination dysarthria, gait ataxia, and left-sided central facial and hypoglossal palsies were determined. MRI of the brain demonstrated diffuse, infiltrative non-enhancing lesions in the pons, both cerebellar hemispheres, the parahippocampal gyrus, and the thalamus. A stereotactic biopsy demonstrated an astrocytoma WHO grade 2. These characteristics confirmed gliomatosis cerebri. Three months later, the patient presented with hydrocephalus and a subcutaneous swelling directly underneath the surgical scar. The subcutaneous swelling was removed and the hydrocephalus was treated by ventriculoperitoneal shunting. Histopathological examination confirmed a subcutaneous manifestation of low-grade oligoastrocytoma. Gliomatosis cerebri with low-grade histology can seed subcutaneously
Inflammatory pseudotumor of the liver: a case report and review of the literature
<p>Abstract</p> <p>Introduction</p> <p>Inflammatory pseudotumor of the liver represents a fairly uncommon pathology. Although it is a benign tumor, the correct diagnosis can be missed.</p> <p>Case presentation</p> <p>We report the case of a 55-year-old Caucasian man, who presented with a one-month history of abdominal pain and weight loss. He was diagnosed with a primary liver tumor by computed tomography and magnetic resonance imaging. Alpha-fetoprotein levels ranged within normal limits. A right posterior sectorectomy was performed. Histopathology revealed an inflammatory pseudotumor of the liver. Our patient remains in good condition one year later.</p> <p>Conclusion</p> <p>Although inflammatory pseudotumor of the liver is usually a benign process, controversy regarding its management still exists. With this case report we review the existing literature and consider hepatectomy as a safe treatment approach.</p
A loss of c-kit expression is associated with an advanced stage and poor prognosis in breast cancer
To evaluate the c-kit expression in breast cancer, 217 invasive ductal carcinomas of the breast were immunohistochemically stained for c-kit protein. The c-kit expression was positive in 59 (27%) of 217 tumours, while the c-kit expression was negative in 158 (73%) of 217 tumours. There was a significant correlation between a negative expression of the c-kit protein and lymph node metastasis (P<0.0001), and the incidence of a negative expression of the c-kit protein increased as the number of the metastatic lymph nodes increased (P=0.0003). The c-kit expression did not significantly correlate with the tumour size, nuclear grade, oestrogen receptor status, MIB-1 counts and p53 protein expression. A univariate analysis indicated the patients with the negative c-kit expression to have a worse disease-free survival (DFS) than those with the positive c-kit expression (P=0.0041), while a multivariate analysis determined lymph node metastases and the MIB-1 counts to be independently significant factors for DFS. In conclusion, a loss of the c-kit expression was found in about three-fourth of invasive ductal carcinoma of the breast and was associated with lymph node metastases. The prognostic implications of the c-kit expression seem to be due to fact that a loss of the c-kit expression is associated with an advanced stage of breast cancer
Menopausal status dependence of the timing of breast cancer recurrence after surgical removal of the primary tumour
Vascular patterns in reactive lymphoid tissue and in non-Hodgkin's lymphoma.
The few studies published on angiogenesis in lymphoma have raised the question of whether or not microvessel density (MVD) is associated with more aggressive disease and have reported the observation that in follicular lymphomas, vessels are mature rather than immature. We investigated MVD and the vascular phenotype within follicular or diffuse large B-cell lymphomas, reactive nodes and tonsils. Vascular phenotype was defined by the expression or loss of reactivity to the antibody LH39 (detecting the LH39 laminin epitope of the basement membrane in mature vessels) and by detection of alpha V beta 3 (expressed on immature vessels). In reactive nodes and in follicular lymphomas, MVD was higher in the paracortex than in germinal centres or in neoplastic follicles. However, in neoplastic follicles an increase in alpha V beta 3-positive endothelium suggested the activation of an angiogenic pathway different from that present in the reactive follicles. In large B-cell lymphomas, MVD was higher than in reactive and neoplastic follicles but lower than in the reactive paracortex. The number of immature vessels (LH39 negative) and of alpha V beta 3-positive vessels was higher than in reactive lymph nodes and follicular lymphoma suggesting that a switch to a different angiogenic pathway has occurred. Finally, we have demonstrated that within reactive and neoplastic follicles vascular regression is occurring, perhaps constraining the growth of reactive follicles alongside other phenomena such as apoptosis. Vascular regression was previously believed to occur in adults only in ovarian and endometrial tissue. We conclude that different types of angiogenesis are present in follicular lymphomas and large B-cell lymphomas. This has implications for possible future therapies
Chronic dorsal subdural haematoma: single aetiology for CNS superficial siderosis and myelopathy
Differential response of immunohistochemically defined breast cancer subtypes to anthracycline-based adjuvant chemotherapy with or without paclitaxel
Background: The aim of the present study was to investigate the efficacy of adjuvant dose-dense sequential chemotherapy with epirubicin, paclitaxel, and CMF in subgroups of patients with high-risk operable breast cancer, according to tumor subtypes defined by immunohistochemistry (IHC). Materials and Methods: Formalin-fixed paraffin-embedded (FFPE) tumor tissue samples from 1,039 patients participating in two adjuvant dose-dense sequential chemotherapy phase III trials were centrally assessed in tissue micro-arrays by IHC for 6 biological markers, that is, estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki67, cytokeratin 5 (CK5), and EGFR. The majority of the cases were further evaluated for HER2 amplification by FISH. Patients were classified as: luminal A (ER/PgR-positive, HER2-negative, Ki67low); luminal B (ER/PgR-positive, HER2-negative, Ki67high); luminal-HER2 (ER/PgR-positive, HER2-positive); HER2-enriched (ER-negative, PgR-negative, HER2-positive); triple-negative (TNBC) (ER-negative, PgR-negative, HER2-negative); and basal core phenotype (BCP) (TNBC, CK5-positive and/or EGFR-positive). Results: After a median follow-up time of 105.4 months the 5-year disease-free survival (DFS) and overall survival (OS) rates were 73.1% and 86.1%, respectively. Among patients with HER2-enriched tumors there was a significant benefit in both DFS and OS (log-rank test; p = 0.021 and p = 0.006, respectively) for those treated with paclitaxel. The subtype classification was found to be of both predictive and prognostic value. Setting luminal A as the referent category, the adjusted for prognostic factors HR for relapse for patients with TNBC was 1.91 (95% CI: 1.31-2.80, Wald's p = 0.001) and for death 2.53 (95% CI: 1.62-3.60, p&lt;0.001). Site of and time to first relapse differed according to subtype. Locoregional relapses and brain metastases were more frequent in patients with TNBC, while liver metastases were more often seen in patients with HER2-enriched tumors. Conclusions: Triple-negative phenotype is of adverse prognostic value for DFS and OS in patients treated with adjuvant dose-dense sequential chemotherapy. In the pre-trastuzumab era, the HER2-enriched subtype predicts favorable outcome following paclitaxel-containing treatment. © 2012 Fountzilas et al