Expression of EpCAM in uveal melanoma

BACKGROUND: Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults, and nearly 40% of UM will develop metastasis that will ultimately lead to death. The Epithelial Cell Adhesion Molecule (EpCAM) is a type I transmembrane glycoprotein expressed by carcinomas of head and neck, ovary, colon, breast, kidney and lung. Recently, antibodies against EpCAM such as Edrecolomab and Catumaxomab were developed, and clinical trials with these antibodies have been used in several types of neoplasia. We studied the expression of EpCAM in UM. METHODS: 25 enucleated formalin-fixed, paraffin-embedded UM specimens were immunostained for EpCAM. Histopathological analysis of the specimens with regards to prognostic factors such as cell type, largest (linear) tumor dimension, number of mitotic figures, scleral invasion and tumor infiltrating lymphocytes were done. RESULTS: None of them was positive for this EpCAM. CONCLUSION: In our report, UM did not express EpCAM. Therefore, it is not a helpful immunohistochemical marker to predict the behavior of UM. Further studies are needed to verify if EpCAM could also be related with prognosis and treatment of UM

Immunohistochemical expression of melan-A and tyrosinase in uveal melanoma

BACKGROUND: Melan-A and tyrosinase are new immunohistochemical markers that can be used in the diagnosis of melanocytic lesions. The aim of this study was to investigate the correlation between radiotherapy or clinicohistopathological parameters and the expression of melan-A and tyrosinase in uveal melanoma. METHODS: Thirty-six enucleated cases of uveal melanoma were studied. The formalin-fixed, paraffin-embedded specimens were immunostained with monoclonal antibodies against melan-A and tyrosinase. The samples were classified as either positive or negative. The chi-square or the Student-t tests were used to test for the correlation of the expression rates of melan-A and tyrosinase with clinico-pathological parameters. RESULTS: Melan-A and tyrosinase were positive in 33 (91.7%) and 35 (97.2%) of the specimens, respectively. There was no significant association between the expression of melan-A or tyrosinase and radiotherapy or any clinico-pathological parameter. All specimens were positive for at least one of the immunohistochemical markers. CONCLUSION: To the best of our knowledge this is the first study concluding that the expression of melanocytic markers such as melan-A and tyrosinase is not influenced by radiotherapy or any clinico-pathological parameter. Moreover, when tyrosinase and melan-A are used together, 100% of the formalin-fixed, paraffin-embedded uveal melanoma samples tested positive for one of those markers

Clinical-histopathological correlation in a case of Coats' disease

Background: Coats' disease is a non-hereditary ocular disease, with no systemic manifestation, first described by Coats in 1908. It occurs more commonly in children and has a clear male predominance. Most patients present clinically with unilateral decreased vision, strabismus or leukocoria. the most important differential diagnosis is unilateral retinoblastoma, which occurs in the same age group and has some overlapping clinical manifestations.Case presentation: A 4 year-old girl presented with a blind and painful right eye. Ocular examination revealed neovascular glaucoma, cataract and posterior synechiae. Although viewing of the fundus was impossible, computed tomography disclosed total exsudative retinal detachment in the affected eye. the eye was enucleated and subsequent histopathological evaluation confirmed the diagnosis of Coats' disease.Conclusion: General pathologists usually do not have the opportunity to receive and study specimens from patients with Coats' disease. Coats' disease is one of the most important differential diagnoses of retinoblastoma. Therefore, It is crucial for the pathologist to be familiar with the histopathological features of the former, and distinguish it from the latter.McGill Univ, Ctr Hlth, Dept Ophthalmol & Pathol, Montreal, PQ, CanadaHenry C Witelson Ocular Pathol Lab, Montreal, PQ, CanadaUniversidade Federal de São Paulo, EPM, Dept Ophthalmol, UNIFESP, São Paulo, BrazilHosp Servidores Estado, Dept Ophthalmol, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, EPM, Dept Ophthalmol, UNIFESP, São Paulo, BrazilWeb of Scienc

The role of c-kit and imatinib mesylate in uveal melanoma

BACKGROUND: Uveal melanoma (UM) is the most common primary intraocular tumor in adults, leading to metastasis in 40% of the cases and ultimately to death in 10 years, despite local and/or systemic treatment. The c-kit protein (CD117) is a membrane-bound tyrosine kinase receptor and its overexpression has been observed in several neoplasms. Imatinib mesylate is a FDA approved compound that inhibits tyrosine quinase receptors, as well as c-kit. Imatinib mesylate controls tumor growth in up to 85% of advanced gastrointestinal stromal tumors, a neoplasia resistant to conventional therapy. METHODS: Fifty-five specimens of primary UM selected from the archives of the Ocular Pathology Laboratory, McGill University, Montreal, Canada, were immunostained for c-kit. All cells displaying distinct immunoreactivity were considered positive. Four human UM cell lines and 1 human uveal transformed melanocyte cell line were tested for in vitro proliferation Assays (TOX-6) and invasion assay with imatinib mesylate (concentration of 10 μM). RESULTS: The c-kit expression was positive in 78.2% of the UM. There was a statistical significant decrease in the proliferation and invasion rates of all 5 cell lines. CONCLUSION: The majority of UM expressed c-kit, and imatinib mesylate does decrease the proliferation and invasion rates of human UM cell lines. These results justify the need for a clinical trial to investigate in vivo the response of UM to imatinib mesylate

Malignancy in the blind painful eye - report of two cases and literature review

Background: Few cases of malignant tumors arising in a blind painful eye have previously been described. We described two cases of a blind painful eye containing an unsuspected tumor, which were enucleated to relieve the pain.Case presentations: Case 1: A 57 year-old Caucasian man presented with recurrent orbital cellulitis and endophthalmitis in the left eye (OS). the OS was blind and painful and an enucleation was performed showing a uveal melanoma by histopathological exam. Case 2: A 54 year-old Caucasian man with previous history of a rhegmatogenous retinal detachment in his left eye presented a blind painful eye. Enucleation was performed revealing a well-differentiated B-cell lymphoma of uveal tract with extra ocular extension.Conclusion: in the management of a blind painful eye, it is extremely important to rule out an intraocular malignancy particularly in those patients who have not been followed by an ophthalmologist.Universidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilMcGill Univ, Dept Ophthalmol, Henry C Witelson Ocular Pathol Lab, Montreal, PQ H3A 2T5, CanadaPathol & Cytopathol Lab, LAC, Campo Grande, MS, BrazilUniv Desenvolvimento Estado & Regiao Pantanal, Campo Grande, MS, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilWeb of Scienc

Cytokeratin expression in corneal dystrophies

PURPOSE: To identify an immunohistochemical pattern of epithelial markers in granular, lattice and Avellino corneal dystrophies. METHODS: Twenty-two corneal buttons, diagnosed as lattice (17), Avellino (4) and granular (1) underwent immunohistochemical studies of cytokeratins (CKs) on pa- raffin-embedded sections (group I). Monoclonal antibodies for pan-CK (AE1/AE3) and CKs 3/12, 5/6, 8, 18 and 19 were used. Twenty-two normal corneas were used as the control (group II). RESULTS: Six lattice and 2 Avellino cases of group I stained positively with anti-CK 3/12 in corneal epithelium and areas of corneal stroma deposits. One of these cases of lattice was positive for anti-pan-CK (AE1/AE3) also in the epithelium and areas of corneal stroma deposits with a similar pattern. None of the controls (group II) revealed any staining in corneal stroma. All disease and control cases (groups I and II) revealed positive staining in corneal epithelium. CONCLUSION: AE1/AE3 and CK 3/12 anti-CK positive markers in the stromal deposits of lattice and Avellino dystrophies may suggest an epithelial genesis of the disease

The effect of blue light exposure in an ocular melanoma animal model

<p>Abstract</p> <p>Background</p> <p>Uveal melanoma (UM) cell lines, when exposed to blue light in vitro, show a significant increase in proliferation. In order to determine if similar effects could be seen in vivo, we investigated the effect of blue light exposure in a xenograft animal model of UM.</p> <p>Methods</p> <p>Twenty New Zealand albino rabbits were injected with 1.0 × 10⁶human UM cells (92.1) in the suprachoroidal space of the right eye. Animals were equally divided into two groups; the experimental group was exposed to blue light, while the control group was protected from blue light exposure. The eyes were enucleated after sacrifice and the proliferation rates of the re-cultured tumor cells were assessed using a Sulforhodamine-B assay. Cells were re-cultured for 1 passage only in order to maintain any in vivo cellular changes. Furthermore, Proliferating Cell Nuclear Antigen (PCNA) protein expression was used to ascertain differences in cellular proliferation between both groups in formalin-fixed, paraffin-embedded eyes (FFPE).</p> <p>Results</p> <p>Blue light exposure led to a statistically significant increase in proliferation for cell lines derived from intraocular tumors (p < 0.01). PCNA expression was significantly higher in the FFPE blue light treated group when compared to controls (p = 0.0096).</p> <p>Conclusion</p> <p>There is an increasing amount of data suggesting that blue light exposure may influence the progression of UM. Our results support this notion and warrant further studies to evaluate the ability of blue light filtering lenses to slow disease progression in UM patients.</p