Acute appendicitis is the most frequent surgical abdominal emergency, but its etiology remains poorly understood. Histological examination of the appendix, following its removal due to acute appendicitis, consistently shows features in common with bronchial asthma, suggesting an allergic reaction as a candidate etiologic factor. Here, we propose the concept of appendicular lavage and use it to study the levels of the Th2 cytokines IL-4, IL-5, and IL-9 in patients with a clinical diagnosis of acute appendicitis. The study group included 20 patients with a histological diagnosis of phlegmonous appendicitis, 13 patients with gangrenous appendicitis, and a control group of 8 patients with a clinical diagnosis of appendicitis but with normal histology. Cytokine levels were higher in acute appendicitis. The difference was more pronounced when comparing phlegmonous appendicitis with nonpathological appendicitis (p = 0.01) for IL-4 (48.3 vs. 21.3 pg/mL), IL-5 (29.2 vs. 8.0 pg/mL), and IL-9 (34.1 vs. 16.6 pg/mL). This Th2 cytokine profile is compatible with the hypothesis of allergy as an etiologic factor for acute appendicitis and may have important implications for the diagnosis, prevention, and treatment of this condition.

Angiosarcoma is a rare, aggressive malignant vascular neoplasm with poor prognosis that has a predilection for skin and superficial soft tissue. It can arise spontaneously or in association with factors like chronic lymphedema or radiation therapy. Radiotherapy used to treat invasive breast tumors is a known risk factor for the development of the so‐called radiation‐induced angiosarcoma (RIAS), a condition that has been described in the literature with increasing frequency. Radiation‐induced angiosarcoma of the breast usually arises on the previously irradiated skin area several years after radiotherapy and presents as painless multifocal erythematous patches or plaques similar to a hematoma. Cutaneous biopsy is essential for the diagnosis. Histologically, RIAS is characterized by irregular anastomosing vessels lined by endothelial cells showing nuclear atypia. Treatment is mostly surgical, and mastectomy with negative margins is considered the standard procedure. However, recurrences are common, and an approach combining surgery, chemo‐ and radiotherapy may be more effective. The purpose of this study is to review the most recent medical literature on RIAS of the breast, with emphasis on its pathophysiology, clinical and histological features and current treatment options.

Background. IgE mediates type I hypersensitivity reaction and can be found in the mucosa of organs affected by allergy. Acute appendicitis (AA) is a common disease, but its etiology remains poorly understood. Here, we investigated IgE deposition in histological sections of AA samples to test the hypothesis that an allergic reaction may substantially contribute to the pathophysiology of AA. Materials and Methods. In a retrospective study, we assessed the presence of IgE in appendicular specimens of histologically confirmed appendicitis and in the control group, comprised of negative appendicitis and incidental appendectomies, using a monoclonal antibody against human IgE. Samples from 134 appendectomies were included: 38 phlegmonous and 27 gangrenous appendicitis from the study group and 52 incidental appendectomies and 17 negative appendicitis from the control group. The slides were visualized by light microscopy, and a standard procedure was used to manually count the positive IgE staining cells. Results. IgE staining was present in the cells of all but 5 appendicular specimens. We found a significantly increased number of IgE-positive cells in phlegmonous AA ( median = 28 ) when compared to incidental appendectomy ( median = 17 ) ( p = 0.005 ; p < 0.0001 when adjusted for age and gender). No difference was found for gangrenous appendicitis. Discussion. The presence of IgE supports the contribution of an allergic reaction for the pathophysiology of phlegmonous appendicitis. The reduced number of IgE staining cells in gangrenous appendicitis can be due to tissue destruction, or, as been claimed by others, gangrenous appendicitis is a distinct entity, with different etiology. Conclusion. In this study, phlegmonous appendicitis had the highest number of IgE-positive appendicular cells. These findings suggest that an allergic reaction can contribute to the pathophysiology of AA, opening a novel possibility for preventive measures in a disease that typically requires surgery.

Appendicitis is the most common abdominal surgical emergency, but its aetiology is not fully understood. We and others have proposed that allergic responses play significant roles in its pathophysiology. Eosinophils and Interleukin (IL)-5 are involved in a hypersensitivity type I reaction. Eosinophil infiltration is common in the allergic target organ and is dependent on IL-5. In the presence of an allergic component, it is expected that the eosinophil count and IL-5 local and systemic concentrations become elevated. To address this hypothesis, we designed a prospective study that included 65 patients with acute appendicitis (grouped as acute phlegmonous or gangrenous according to the histological definition) and 18 patients with the clinical diagnosis of acute appendicitis, but with normal histological findings (control group) were enrolled. Eosinophil blood counts and appendicular wall eosinophil infiltration were determined. IL-5 levels in blood and appendicular lavage fluid were evaluated. Appendicular lavage fluid was collected by a new methodology developed and standardized by our group. Appendicular wall eosinophil infiltration was higher in acute phlegmonous appendicitis than in gangrenous appendicitis (p = 0.000). IL-5 blood levels were similar in both pathologic and control groups (p > 0.05). In the appendicular lavage fluid, the higher levels of IL-5 were observed in the phlegmonous appendicitis group (p = 0.056). We found a positive correlation between the appendicular wall eosinophilic infiltration and the IL-5 concentrations, in both the blood and the appendicular lavage fluid, supporting the IL-5 reliance in eosinophil local infiltration. We observed the highest presence of eosinophils at phlegmonous appendicitis walls. In conclusion, the present data are compatible with a hypersensitivity type I allergic reaction in the target organ, the appendix, during the phlegmonous phase of appendicitis.

Introduction: Approximately 20% - 30% of histological lymph node-negative patients with colorectal cancer relapse at five years after surgical treatment. This recurrence is likely due to occult nodal disease undetected by standard histopathological practice which has implications in terms of the clinical management of patients.Material and Methods: Lymph nodes were collected from colectomy specimens. A central section from each lymph node was histologically examined following haematoxylin-eosin staining and the remaining tissue was subjected to OSNA - one step nucleic acid amplification analysis.Results: A total of 1046 lymph nodes from 59 pN0 patients were assessed. Of these, 753 lymph nodes were examined by both methods. The median number of lymph nodes assessed with OSNA - one step nucleic acid amplification was 12 (IQR: 7;16). Among pN0 patients, 17 had OSNA - one step nucleic acid amplification-positive lymph nodes, resulting in a positive molecular staging rate of 28.8% (95% CI: 17.8 - 42.1). Among these patients, 12 (70.59%) were molecular-staged as pN1 and 5 (29.41%) were molecular staged as pN2. The tumour burden of lymph nodes assessed with OSNA - one step nucleic acid amplification ranged from 270 to 17 000 cytokeratin 19 mRNA copies/μL. Most of these patients (88.2%) were found to have lymph nodes with micrometastases only (250 - 4999 copies/μL).Discussion: We provide the results from the first study of the use of the OSNA - one step nucleic acid amplification assay in colorectal cancer patients in Portugal. Our results are in-line with other international studies, showing the improvement on patients’ staging by molecular examination of lymph nodes.Conclusion: In our study, 28.8% of patients with histologically negative lymph nodes were found to have metastatic lymph nodes using OSNA - one step nucleic acid molecular assessment. OSNA - one step nucleic acid assay allows a more accurate staging of patients with colorectal cancer and standardizes lymph node assessment.