Aberrant wound-healing response in mitomycin C-treated leaking blebs: a histopathologic study.

OBJECTIVE: To characterize histopathologic features of leaking mitomycin C-treated blebs and aberrant wound healing that may lead to persistent conjunctival thinning and leakage. METHODS: Forty mitomycin C-treated filtering blebs excised for persistent leaks from 40 patients were examined histopathologically using hematoxylin-eosin, periodic acid-Schiff, Masson trichrome, and Alcian blue histochemical stains. RESULTS: Ninety percent of the leaking blebs contained epithelial-stromal domes with areas of acellular stroma covered by attenuated epithelium. Seventy-five percent of the blebs demonstrated varying degrees of fibrovascular repair growing from the bleb margin, either beneath or interdigitating with the acellular zone. A novel observation in 65% of specimens was Alcian blue-positive myxoid stroma at the interface between the fibrovascular proliferation and the epithelial-stromal dome. The association between the presence of fibrovascular proliferation and Alcian blue-staining myxoid stroma was significant by Fisher exact test (P = .002). CONCLUSIONS: A desirable filtration bleb requires a sufficient reparative fibrovascular response to maintain an epithelial-stromal barrier to prevent leakage. Fibroblasts must lay down a continuous collagen-rich fibrous layer, rather than merely myxoid stroma, beneath the conjunctival epithelium to promote bleb stability. Surgical techniques and postsurgical care should aim to attain this desired outcome.

Intraocular tissue migration of silicone oil after silicone oil tamponade: a histopathological study of enucleated silicone oil-filled eyes.

Retrospective clinical and histopathological review of eight silicone oil-filled enucleated eyeballs using light microscopy was carried out in our department of ocular pathology during a period of six years. In all cases, silicone oil vacuoles, both free and incorporated within macrophages were seen in all the retinal layers. Silicone oil vacuoles were seen in the optic nerve, choroid, retinal pigment epithelium, corneal stroma, iris and ciliary body stroma, preretinal and subretinal membranes and retro-corneal membranes. Silicone oil migration could be seen in intraocular tissues as early as two months post surgery. There was no definite histopathological correlation between duration of tamponade and distribution of silicone oil vacuoles. Silicone oil vacuoles were seen in the optic nerve in eyes with neovascular glaucoma. Chronic inflammatory reaction was observed in the retinal tissue in the vicinity of silicone oil vacuoles.

Expression of epidermal growth factor receptor, ezrin, hepatocyte growth factor, and c-Met in uveal melanoma: an immunohistochemical study.

The immunoreactivity of epidermal growth factor receptor (EGFR) ezrin, hepatocyte growth factor receptor (HGF), and c-Met was studied in 60 uveal melanomas and was correlated with clinicopathologic parameters. Metastases were diagnosed in the patients with uveal melanoma between 5 years and 8 years (median, 6.5 years) after enucleation. Using Kaplan-Meier statistical analysis, we found a significant association between high c-Met expression and death due to uveal melanoma (p < 0.03). EGFR was expressed in 18 of 60 (30%) tumors; ezrin was expressed in 30 of 60 (50%) tumors. Tumors with liver metastasis (n = 6) showed higher expression of c-Met (p = 0.0009) compared with the tumors with no extension/extrascleral extension without liver metastasis (groups A-45 and B-9). HGF was negative in all the six tumors that had liver metastasis. Further studies are required to understand the possible mechanism of ligand-independent c-Met activation in patients with uveal melanoma.

Expression of insulin-like growth factor receptor (IGF-1R), c-Fos, and c-Jun in uveal melanoma: an immunohistochemical study.

The immunoreactivity of insulin-like growth factor receptor type 1 (IGF-1R), c-Fos, and c-Jun by immunohistochemistry was studied in three groups of uveal melanomas and was correlated clinicopathologically. Immunoanalysis was correlated with cell types, largest tumor diameter, tumor-infiltrating lymphocytes, mitosis, nuclear grade, and extrascleral extension/liver metastasis. In group C (n = 6), tumors with liver metastasis showed higher expressions of IGF-1R (p = 0.0001), c-Fos (p = 0.004), and c-Jun (p = 0.018) compared with the tumors with no extension/extrascleral extension without liver metastasis (groups A-45 and B-9). Further studies are required to elucidate the role of sequential upregulation of these proteins and the transcriptional activity of c-Fos and c-Jun in uveal melanomas with liver metastasis

HLA expression in choroidal melanomas: correlation with clinicopathological features.

PURPOSE: In this retrospective study, we analyzed the relevance of human leukocyte antigen (HLA) expression to clinical behavior of uveal melanoma and correlated it with conventional light microscopic parameters. METHODS: HLA class I antigen and Beta 2 microglobulin expression were analyzed in 45 primary choroidal melanoma lesions by immunoperoxidase staining with monoclonal antibodies to HLA class I antigen and beta 2 microglobulin and correlated with the known clinicopathological parameters. Immunoanalysis was done by a semi quantitative method. The tumors were divided into 3 groups. Group A: Tumors with no extrascleral extension/no liver metastases, group B: tumors with only extrascleral extension and group C: tumors with liver metastases. For statistical analysis we analyzed the negative, weak (heterogeneous) and the positive expression of HLA and beta 2 microglobulin with known clinicopathological parameters. RESULTS: In-group A (n = 35) tumors with no extrascleral extension and no liver metastases HLA class I antigen and beta 2 microglobulin are negative (absent staining) in 30 choroidal melanomas. In-group B (n = 4) they are weak (heterogeneous) in 3 tumors. In-group C (n = 6) all the 6 tumors have a positive (bright staining) immunoexpression. No statistical significance was obtained when HLA and beta 2 microglobulin immunoreactivity was compared against largest tumor diameter (LTD), tumor infiltrating lymphocytes (TIL), mitosis and nuclear grade. The difference of HLA class I and beta 2-microglobulin imunoreactivity among the various cell types spindle, mixed and epithelioid was statistically significant (p = 0.003), (p = 0.004). The difference in immunoreactivity between tumors with no liver metastases and tumors with liver metastases was statistically significant (p < 0.001). CONCLUSIONS: HLA class I antigen and beta 2 microglobulin are negative in melanomas with no extrascleral extension and liver metastases and weak in melanomas with extrascleral extension and are positive in melanomas with liver metastases. HLA expression is independent of the conventional markers in uveal melanoma.

Major histocompatibility antigens and antigen-processing molecules in uveal melanoma.

PURPOSE: Malignant transformation of cells is frequently associated with abnormalities in the human leukocyte antigen (HLA) expression. These abnormalities may play a role in the clinical course of the disease, because HLA antigens mediate interactions of tumor cells with T cells and natural killer cells. Uveal melanoma is a highly malignant tumor of the eye and is characterized by hematogenic spread to liver. Antigen-processing molecules (APMs) are necessary for efficient expression of HLA class I antigens. We studied the expression of HLA antigens and the APM in uveal melanomas by immunohistochemistry and correlated clinicopathologically. EXPERIMENTAL DESIGN: HLA class I antigen, beta(2)-microglobulin (beta(2)-m), HLA class II antigens, and the APM comprising proteasomal subunits low molecular mass polypeptide (LMP) 2, beta-subunit of LMP2-Delta, LMP 10, transporter associated protein 1 subunit, and chaperone molecules tapasin and calnexin were studied in 41 primary uveal melanoma archival specimens by immunohistochemistry. Immunoanalysis was done by a semiquantitative method and correlated with extrascleral extension, cell types, and the largest tumor diameter. RESULTS: HLA class I antigen, beta(2)-m, HLA class II antigen, and the APM were decreased (negative staining in 29 tumors and dull staining in 3 tumors) in 100% (32 of 32) uveal melanomas with no extrascleral extension. (P = 0.01) and positive (bright staining) in 67% (4 of 9) tumors with liver metastasis. Decreased immunoexpression of HLA antigens and the APM was seen in nonepithelioid cell melanomas. There was no correlation with largest tumor diameter. CONCLUSIONS: Our data suggest decreased expression of HLA, and APM are seen in uveal melanomas with no extrascleral extension and in nonepithelioid cell melanomas. Decreased expression of APM may contribute to decreased HLA class I antigen expression.

HLA class II antigen expression in conjunctival precancerous lesions and squamous cell carcinomas.

PURPOSE: The expression of human leukocyte antigen (HLA) class II molecules on the cell surface is necessary for the presentation of peptide antigens to helper CD4 T lymphocytes of the immune system. We studied the immunoexpression of HLA class II antigen in conjunctival precursor lesions and conjunctival squamous cell carcinomas. METHODS: HLA class II antigen expression was analyzed in 8 conjunctival dysplasias, 6 carcinomas in situ and in 7 conjunctival squamous cell carcinomas, by immunoperoxidase staining with monoclonal antibody to HLA class II antigen on the archival clinical samples. Immunoanalysis was done by a semi quantitative method based on the intensity of staining and the percentage of stained cells. RESULTS: HLA class II antigen immunoexpression was heterogeneous in 8 conjunctival dysplasias and in 6 carcinoma in situ and negative in 7 conjunctival squamous cell carcinomas. CONCLUSIONS: Human leukocyte class II antigen immunoexpression is decreased in conjunctival precancerous and squamous cell carcinomas.

HLA class II antigen expression in uveal melanoma: correlation with clinicopathological features.

The authors examined the immunoexpression of human leukocyte (HLA) class II antigen in uveal melanomas and correlated with the cell types, largest tumour dimension and extrascleral invasion. HLA class II antigen expression was analysed in 45 primary uveal melanoma lesions by immunoperoxidase staining with monoclonal antibody. Immunoanalysis was done by a semi-quantitative method according to the International Histocompatibility Working Group, Project description. The results were correlated clinicopathologically. Among the 45-uveal melanomas, 17 were spindle cell types, 16 were mixed cell types and 12 were epithelioid cell types. Among the 35 tumours with no extrascleral extension, HLA class II antigen was decreased in (100%) 35/35 tumours. Among the 10 tumours with extrascleral extension, HLA class II antigen was positive in the 60% (6/10) tumours with liver metastasis and decreased in 40% (4/10) tumours with no liver metastasis. HLA class II antigen was negative in 94% (16/17) spindle cell melanomas. Decreased HLA class II immunoreactivity in tumours with no extrascleral extension was significant (P<0.001). Negative HLA class II immunoreactivity in the spindle cell melanoma was significant (P<0.001). There was no correlation with largest tumour diameter and immunoreactivity. HLA class II antigen is an independent prognostic marker in uveal melanoma. Thus, HLA class II antigen expression in uveal melanoma in relation to prognosis and cell types are similar to HLA class I antigen expression, where downregulation and presence of spindle cell melanoma correlates with favourable outcome. This may have important implications with respect to proposed T cell based immunotherapy.