Mannose-Binding Lectin Deposition in Membranous Nephropathy and Differentiation of Primary from Secondary Forms.

The differentiation between primary and secondary forms of membranous nephropathy (MN) is a cornerstone that is necessary for adequate decision making regarding the treatment options and behavior of each specific case. Kidney biopsy and antibody results can be controversial, and a unique biomarker has still not been found. BACKGROUND AND OBJECTIVES: We investigated the lack of mannose-binding lectin (MBL) deposition in patients with secondary MNs (sMNs) with the presence of IgG4 deposition in relation to the presence of MBL deposition in patients with primary MNs (pMNs). We also established a connection between the stage of MN and MBL deposition. MATERIALS AND METHODS: Materials from 72 renal biopsies with proven MN were used for immunohistochemistry staining (IHC) for the phospholipase A2 receptor (PLA2R), immunoglobulin subtype IgG4, and MBL. Patients were separated into one of the following three groups: primary MN (pMN), idiopathic MN (iMN), and secondary MN (sMN). Serum antibodies for PLA2R and thrombospondin type-I-domain-containing 7A (THSD7A) were also used for the precise evaluation of the type of MN, as well as for detecting positivity for PLA2R using IHC. Which stage of MN was present in relation to the deposition of MBL was evaluated. RESULTS: In total, 50 patients were positive for IgG4, 34 with pMN, 12 with iMN, and 4 with sMN. A total of 20 patients were positive for MBL, 14 with pMN and 6 with iMN; no MBL deposits were found in patients with sMN. MBL positivity was predominantly present in the first two stages of MN, with a gradual reduction in the later stages. CONCLUSIONS: The activation of the lectin-complement pathway occurs in the early stages of the disease and is associated with the deposition of IgG4; IgG4 deposition is present in sMN, but there is no MBL deposition. IgG4 cannot be used for the differentiation of primary from secondary MNs, but the lack of MBL can be used as a marker for sMN in the early stages of the disease.

Leiomyosarcoma of the esophagus, arising from lamina muscularis mucosae, in a combination with microinvasive squamous cell carcinoma-A case report.

ABSTRACT: Leiomyosarcoma of the esophagus is a very rare disease, accounting for less than 0.5% of malignant esophageal tumors. Esophageal leiomyosarcoma combined with squamous cell carcinoma is even rarer than solitary leiomyosarcoma. To our knowledge, there are less than ten cases of simultaneously diagnosed leiomyosarcoma and squamous cell carcinoma of the esophagus. A 66-year-old male was admitted to our hospital suffering from epigastric pain, asthenia, weight loss, and difficulties when feeding with solid food which had been present for 2 weeks. A computed tomography scan showed a large tumor tissue mass in the mid-to-distal part of the esophagus. The patient underwent robot-assisted surgery-an esophagectomy with esophagogastrostomy. Histologically, the tumor consisted of highly pleomorphic spindle cells with multiple atypical mitosis and necrotic areas. An immunohistochemical examination was performed to distinguish leiomyosarcoma from spindle cell squamous carcinoma or malignant GIST. Tumor cells stained diffusely positive for smooth muscle actin, but negative for p63, CD117, and CKAE1/AE3. Tumor invasion involved mucosa and submucosa, without tunica muscularis propria. Microinvasive well-differentiated squamous cell carcinoma was also noted in the mucosa at the borders between the tumor and the healthy part of the esophagus. The aim of the manuscript is to present an extremely rare case of combined polypoid leiomyosarcoma and microinvasive squamous cell carcinoma of the esophagus, cured by robot-assisted surgical intervention and to emphasize that such cases should be examined carefully, including additional diagnostic tests such as Immunohistochemistry (IHC) in order to define the correct diagnosis.

Lectin complement pathway and diabetes mellitus in the pathogenesis of membranous nephropathy.

INTRODUCTION: Membranous nephropathy (MN) is a glomerulonephritis with growing incidence and its pathogenesis still remains unclear, despite discoveries of many new antigens. The understanding of MN pathogenesis has moved from antigen-antibody arena to the complement activation through the lectin pathway.

Malignant gastrointestinal stromal tumor in association with Russell body gastritis-A case report.

Russell body gastritis (RBG) is an unusual form of chronic inflammation characterized by accumulation of plasma cells containing Russell bodies (RB) in the gastric mucosa. Although its pathogenesis has not been fully evaluated, there is evidence to support a strong association with Helicobacter pylori infection. Only four cases of RBG in association with malignant epithelial gastric tumors were reported. We report the first case of RBG in peritumoral mucosa of a malignant gastrointestinal stromal tumor in association with coccoid form of Helicobacter pylori and a follow-up.

The Epithelial-Mesenchymal Transition, E-cadherin and Tumor Progression in Ovarian Serous Tumors.

BACKGROUND: The epithelial-mesenchymal transition (EMT), which is a change in the cell phenotype from epithelial to mesenchymal morphology, is an important step in the invasion process and metastasis of ovarian carcinomas. It is known that the suppression of cell adhesion molecules such as E-cadherin and the expression of mesenchymal markers such as Vimentin are key processes in EMT. There is controversy in the literature about the EMT status of ovarian carcinomas. AIM: To investigate EMT status using immunohistochemical expression of E-cadherin in benign, primary malignant serous ovarian tumors and metastases from them in order to assess their significance in tumor progression. MATERIALS AND METHODS: The study included a retrospective investigation of 217 ovarian epithelial tumors. Ninety-two cases of serous ovarian tumors and metastases were examined for expression of E-cadherin. RESULTS: In our study, the predominant histological subtype in benign ovarian tumors and carcinomas was serous (73% and 61%, respectively). 65% of benign tumors demonstrated EMT negative status. The majority of carcinomas demonstrated EMT positive status (82%), whereas negative EMT status was only observed in 18% of cases. 89% of the metastases showed EMT positive status, whereas only 11% of them showed negative EMT status. In 6 selected cases with positive EMT status we found Vimentin expression in tumor cells. CONCLUSION: Positive EMT status (reduced E-cadherin expression) is a characteristic of ovarian carcinomas and metastases, but not of benign serous ovarian tumors.