Cytologic features of chordoid meningioma. A case report.

BACKGROUND: Chordoid meningioma is a rare subtype of meningioma characterized by myxoid matrices deposited among epithelioid or vacuolated tumor cells and infiltrates of inflammatory cells, and its cytologic features have rarely been reported. CASE: A 57-year-old man with a history of headache and visual disturbance presented with a tumor in the suprasellar region. Intraoperative touch smear cytology of the tumor disclosed a cord-like arrangement of polygonal tumor cells occasionally containing intranuclear inclusions. Furthermore, periodic acid-Schiff-positive, mucinous matrices were deposited among the tumor cells. Also, infiltrates of lymphocytes and plasma cells were noted. Histologic, immunohistochemical and ultrastructural examination confirmed the diagnosis of chordoid meningioma. CONCLUSION: Intraoperative smear cytology in a case of chordoid meningioma showed distinctive cytologic features suggestive of the histologic patterns. The cytologic features, together with a histologic examination, are useful for its diagnosis.

Clinicopathological correlation of polypoidal choroidal vasculopathy revealed by ultrastructural study.

AIMS: To describe the clinical and histopathological findings in a patient with polypoidal choroidal vasculopathy. METHODS: A 76 year old Japanese man had a discrete, orange-red lesion of 1 disc diameter in the macula, with the fluorescein and indocyanine green angiographic and optical coherence tomographic findings compatible with polypoidal choroidal vasculopathy. He underwent a surgical removal of the macular lesion, followed by light and electron microscopic examinations. RESULTS: The histopathological examination revealed that the specimen consisted of degenerated retinal pigment epithelium-Bruch's membrane-choriocapillaris complex and inner choroid. A tortuous, unusually dilated venule was present adjacent to an arteriole with marked sclerotic changes, appearing to form arteriovenous crossing. These vessels seemed to represent native inner choroidal vessels, and had haemorrhage per diapedesis. Blood cells and fibrin filled the lumina of the vessels and accumulated in the extravascular spaces, indicating vascular stasis. CONCLUSION: Hyperpermeability and haemorrhage due to stasis of a dilated venule and an arteriole involved by sclerosis at the site where they cross in the inner choroid might cause oedema and degeneration of the tissue. Voluminous accumulation of blood cells and fibrin might generate elevation of tissue pressure sufficient to displace the weakened lesion anteriorly. The result suggests that the polypoidal vessels in this case represent abnormality in the inner choroidal vasculature.

Additional cell damage after transpupillary thermotherapy in choroidal malignant melanoma.

The aim of this study was to evaluate the effectiveness of transpupillary thermotherapy (TTT) in generating tumour necrosis by light and electron microscopy, as well as to evaluate additional cell damage in the area directly adherent to the necrotic zone. Four eyes of four patients diagnosed with intraocular malignant melanoma of the uvea were treated experimentally with diode laser TTT. In all cases a standard technique was used. All eyes were enucleated: one eye the day after TTT, two eyes 2 days after TTT, and one eye 6 weeks after TTT. Immediately after enucleation the eyes were immersed in standard Karnovsky's fixative with cocodylate buffer and prepared for light and electron microscopy. In the treated area of all four melanomas we found a dense band of necrotic tissue (zone A) consisting of an amorphous mass of dead cells sharply demarcated from the rest of the neoplastic tissue. Next to this zone was a more eosinophilic and also sharply demarcated band (zone B) that consisted of similar but less intensive changes. In the next band (zone C), marked injury to the cellular membrane and subcellular structures were seen on electron microscopy. The next band (zone D) consisted of changes mainly observed only within the cytoplasm of neoplastic cells and significantly less intensive than those in zone C. Outside zone D tumour cells that were normal in appearance were seen. No scleral alterations induced by heat were found. We concluded that after TTT the cytotoxic effect gradually decreases in proportion to the distance from the central point of the diode laser spot, with additional cell damage in the area adjacent to the necrotic zone. The interval between TTT and enucleation had no influence on the histological results.

Choroidal schwannoma: immunohistochemical and electron-microscopic study.

Schwannoma (neurilemoma) arising from the ciliary body and choroid is a rare form of intraocular tumor and usually misdiagnosed clinically as amelanotic melanoma. This case report describes a 73-year-old woman who developed a large nonpigmented intraocular tumor of the choroid in the left eye and underwent enucleation with a clinical diagnosis of malignant melanoma. The tumor consisted of spindle-shaped cells with an indefinite cytoplasm and twisted nuclei, which had positive immunoreactivity for S-100 protein, vimentin, glial fibrillary acidic protein and neural cell adhesion molecule. A continuous basal lamina encompassing the tumor cells was demonstrated by immunostaining for laminin and type IV collagen. Ultrastructurally, tumor cells with scant organelles had delicate cytoplasmic processes apposing each other, all indicative of Schwann cell origin. In reexamination of fluorescein angiograms, ultrasonograms and magnetic resonance images, no findings were incompatible with a diagnosis of choroidal melanoma. Histopathological studies showed that the tumor was a schwannoma. At present, we do not have a benchmark for the clinical diagnosis of intraocular schwannoma.

Effect of dacarbazine (DTIC) on cultures from malignant melanoma of the choroid: an immunohistochemical and electron microscopic study.

INTRODUCTION: Dacarbazine (DTIC) is a very effective chemotherapeutic agent used in the treatment of cutaneous melanoma; it also could have a potential therapeutic value as an antimetastatic agent in the treatment of choroidal melanoma. OBJECTIVE: To study the HMB-45 and S100 protein expression in choroidal melanoma cultures with and without DTIC, and compare the immunohistochemical and electron microscopic changes in both groups. METHODS: Five- and seven-day cultures of choroidal melanoma (n = 21) were cultivated in diffusion chambers. The cultures were divided in two groups: I group (control group)--the cells were grown in 199-medium; II group--the cells were in 199-medium supplemented with 0.03 mg/ml of DTIC. Immunohistochemical studies were performed with paraffin-embedded material of the cultures by the avidin-biotin-alkaline phosphatase technique. Araldit-embedded material was studied by electron microscopy. RESULTS: The expression of HMB-45 and S100 protein in the cultures with DTIC ranged from slightly positive to negative. The tumor cells were severely damaged. Electron microscopy in this group showed presence only of cellular fragments. In the DTIC-free group the HMB-45 and S100 expressions were strongly positive. There were no electron microscopic evidence of cellular death. CONCLUSION: DTIC suppresses the growth of choroidal melanoma in vitro. These results indicate that further studies are warranted to elucidate the effect of DTIC in vivo.

Benign fibrous histiocytoma of the choroid.

Benign fibrous histiocytoma (BFH) is a common soft tissue tumour. However, its occurrence in the orbit was not well recognised in the past. It is only in recent years that this condition has become more frequently diagnosed. Now, it is believed to be the commonest mesenchymal tumour of the orbit in adults. Its occurrence in the uveal tract is, however, exceedingly rare. Only one case of presumed fibrous histiocytoma of the choroid has been reported in the literature. We report herein a case of BFH of the choroid in the left eye of a Chinese woman. The patient presented with a huge but asymptomatic raised choroidal mass. Results of choroidal biopsy showed no sign of malignancy but definitive diagnosis could not be made. Enucleation was finally performed. The diagnosis was made on detailed evaluation of the results of the immunohistochemical staining and the ultrastructural findings. The patient remained well at the latest follow-up, which was 33 months after enucleation. Although BFH of the choroid is vary rare, its benign nature and the availability of choroidal biopsy for tissue diagnosis make it important to include this as one of the differential diagnoses for amelanotic choroidal mass.

Mean of the ten largest nucleoli, microcirculation architecture, and prognosis of ciliochoroidal melanomas.

BACKGROUND: Cytomorphometric measurements and the architecture of the microcirculation in tissue sections of eyes removed for ciliary body or choroidal melanomas have been identified independently as prognostically significant factors for survival. The relative significance of these two histologic features is addressed in this study. METHODS: The same 234 cases used to assess the prognostic significance of the microcirculatory patterns of choroidal and ciliary body melanomas were examined by two independent observers who measured the largest diameter of melanoma cell nucleoli from digitized images at a high magnification (x 3000) using the laser scanning confocal microscope. The mean of the ten largest nucleoli was calculated for each tumor according to previously published methods. Intraobserver and interobserver reproducibility was assessed for these measurements. Several Cox multiple regression models were constructed which included this cytomorphometric variable with and without the inclusion of the microcirculatory patterns. RESULTS: There is a high degree of intraobserver reproducibility but only a weak degree of interobserver reproducibility in measuring the mean of the ten largest nucleoli. Using multiple Cox regression models, the mean of the ten largest nucleoli from each observer failed to exert any effect on outcome after enucleation, regardless of whether the presence of networks of closed vascular loops was considered in the statistical formulation. The presence of networks of closed vascular loops was found to be the most statistically dominant histologic prognostic characteristic. CONCLUSION: The authors have not been able to confirm the use of the mean of the ten largest nucleoli as a significant prognostic factor in the outcome of patients whose eyes have been removed for ciliary body or choroidal melanomas. Further investigation of this cytomorphometric technique by other laboratories is warranted.

Melanotic schwannoma of the choroid. Immunohistochemistry and electron microscopic observations.

PURPOSE: The purpose of this article is to describe what is probably the first reported case of a melanotic schwannoma of the choroid and to discuss the clinical and histopathologic features that serve to differentiate this rare intraocular tumor from a malignant melanoma of the choroid. PATIENT AND METHODS: A 21-year-old woman underwent enucleation of the right eye for a slowly enlarging pigmented choroidal mass that was associated with ipsilateral blindness. The tumor was studied by light microscopy, immunohistochemistry, and electron microscopy. FINDINGS: The tumor was composed of fascicles and whorls of pigmented and nonpigmented plump spindle cells that had light microscopic features of a schwannoma. The tumor cells showed immunoreactivity to S-100 protein and HMB-45. Electron microscopy showed cytoplasmic processes surrounded by a continuous basement membrane and abundant extracellular collagen. The pigmented spindle-shaped cells contained melanosomes in different stages of melanogenesis. The findings were compatible with a melanotic schwannoma. CONCLUSION: Melanotic schwannoma has been reported in soft tissues, peripheral nerves, and in the orbit. To the authors' knowledge, this is the first report of a melanotic schwannoma of the choroid. This extremely rare pigmented choroidal tumor may be very difficult to differentiate clinically from choroidal melanoma.

Possibilities and limitations of radioimmunoscintigraphy and conventional diagnostic modalities in choroidal melanoma.

A prospective clinical study to assess the value of immunoscintigraphy with a monoclonal antibody (MoAb) against high molecular weight melanoma associated antigen (225.28S) was performed in 43 patients with choroidal melanoma; in six patients with a lesion suspected of being choroidal melanoma, and in seven patients with a benign lesion simulating a choroidal melanoma. The results of immunoscintigraphy in choroidal melanoma were compared with results of conventional diagnostic modalities like ultrasonography and fluorescein angiography. Planar scintigraphy showed a detection rate of 49% which is comparable with other studies. The detection with scintigraphy was correlated to the size of the choroidal melanoma. The use of single photon computed tomography did not increase the sensitivity of immunoscintigraphy. Ultrasonography yielded a correct diagnosis in 37 of 42 melanomas (88%). With fluorescein angiography a correct diagnosis was obtained in 11 of 30 melanomas (36.6%). The value of immunoscintigraphy with MoAb 225.28S in small choroidal melanomas is limited; its reliability increases in large tumours. Immunohistochemistry with MoAb 225.28S showed antigen expression in 95% of the stained tissue specimens of choroidal melanoma.

[The ultramicroscopic aspects in malignant choroidal melanoma]. / Aspecte ultramicroscopice în melanomul malign coroidian.

The survey focuses on the observation using the electronic microscope of two cases of uveal malignant melanoma. The ultrastructure of the cellular population which from this type of malignant tumour was followed, mentioning both the common and the particular aspects. The nuclear and nucleolar modifications, indicating an increase degree of atypia for the epithelioid cells compared with the fusiform cells, were observed. Some aspects of the abnormal tumoural cells were also emphasized. We noticed in the structure of the tumours, besides the tumoural cells, another structure of non-tumoural macrophage and reticular cells, and we described their ultrastructure.

[The characteristics of the nucleolar organizer in tumors of the choroid of the eye]. / Kharakteristika iadryshkogo organizatora v opukholiakh sosudistoi obolochki glaza.

26 intraocular melanomas were studied histologically, ultrastructurally and morphometrically. For the first time the impregnation method was used for visualization of the nucleolar organizer (NO) in the cells of eye tumors using silver salts on the deparaffined sections. The efficiency and reliability of this method in the determination of the degree of malignancy of intraocular melanomas are demonstrated. A correlation existed between long-term postoperative results and the nucleolar organizer index (NO number/number of nuclei). The method can be practiced in any pathohistologic laboratory.

Significance, specificity, and ultrastructural localization of HMB-45 antigen in pigmented ocular tumors.

PURPOSE: To evaluate the expression of the monoclonal HMB-45 antibody in melanocytic and nonmelanocytic ocular tumors and seek "activated" cellular subpopulations in an attempt to distinguish between benign and malignant melanocytes, to compare HMB-45 and S100 activity, and to determine the specificity of this tumor marker for melanocytic ocular lesions. METHODS: Immunohistologic investigations were performed with paraffin-embedded tissue of 10 acquired conjunctival melanoses, 19 conjunctival nevi, 34 conjunctival melanomas, 69 uveal melanomas, 20 basal cell carcinomas of the lid, 20 cystic dermoids, 15 hemangiomas of the lid, 20 conjunctival papillomas, 20 squamous cell carcinomas, 20 pterygia, 11 sebaceous gland carcinomas, 10 retinoblastomas, and 5 choroidal metastatic carcinomas. The avidin-biotin peroxidase technique and monoclonal HMB-45 antibody were used. The distribution of S100 protein was studied in the melanocytic tumors for comparison. To localize the HMB-45 antigen, lowicryl-embedded tissue of uveal melanomas was investigated immunoelectron microscopically. RESULTS: More than 95% of the conjunctival and choroidal melanomas expressed the HMB-45 antigen, while S100 was found in all melanomas of the conjunctiva and in 91% of the uveal melanomas. In benign melanocytic lesions of the conjunctiva (nevi and melanocytes), especially the intraepithelial and junctional components stained with HMB-45, and at the site of tumor invasion, infiltrating cells showed increased HMB-45 reactivity. On the whole, HMB-45 antigen was less evenly distributed in the melanocytic tumors investigated than S100 antigen. All nonmelanocytic ocular tumors revealed no HMB-45 expression. Retinal pigment epithelium and tumor-free choroid were negative for HMB-45. The HMB-45 antigen was immunoelectron microscopically found in melanosomes at stages II and III. CONCLUSION: HMB-45 immunohistology helps in distinguishing melanocytic from nonmelanocytic ocular tumors and often clarifies the front of tumor invasion. The stronger HMB-45 reactivity probably reflects melanocytic activation, but a sharp line between benign and malignant melanocytes cannot be drawn.

Ultrasound biomicroscopy of anterior segment tumors.

BACKGROUND: Ultrasound biomicroscopy is a new method of imaging the anterior segment of the eye at microscopic resolution using high frequency ultrasound. METHODS: A prospective study was performed to evaluate the use of ultrasound biomicroscopy in imaging anterior segment tumors. Forty-five patients underwent clinical examination followed by slit-lamp photography, anterior segment B-scan ultrasonography, and ultrasound biomicroscopy according to an established protocol. RESULTS: All lesions were clearly imaged by ultrasound biomicroscopy, while only 17 were detectable by conventional B-scan ultrasound. Ultrasound biomicroscopy allowed precise measurement and visualization of subsurface features in small tumors. Differentiation between solid and cystic lesions was easily achieved. The margins of ciliary body tumors could be more accurately defined. Histopathologic correlation was possible in four cases managed surgically. Ultrasound biomicroscopy images compared favorably with low-power microscopy. No complications were encountered. CONCLUSION: Ultrasound biomicroscopy proved a valuable new noninvasive technique in the evaluation of anterior segment tumors.

Spindleform scleropathy: collagen changes of the sclera. A pathologic report.

To our knowledge, this is the first pathologic report of interscleral collagen bundle changes occurring as well-defined spindleform lesions randomly interspersed within the sclera. The lesions were observed in an otherwise healthy 75-year-old man whose eye was enucleated because of a uveal malignant melanoma. There are few reports in the literature of focal scleral changes of a predominantly acid mucopolysaccharide nature. The entity we observed in this case differs from these reports by its spindleform appearance, random distribution (not overlying the melanoma) and predominantly vicinal glycol nature. Histopathologic, histochemical, and ultrastructural studies revealed that the lesions were not the result of mucoid degeneration of the scleral collagen and not an abnormal collagen structure.

Orbital squamous cell carcinoma after retinal detachment surgery.

We report on a 76-year-old patient with a squamous cell carcinoma of the left orbit. The tumour had no connection with the conjunctiva but was located at the site of an encircling band which had been inserted 13 years before. A major part of the tumour presented as a well circumscribed solid mass within the extraocular tissues next to the inferior equator, but the exenteration specimen also showed tumour extension within the adjacent choroid. Histological examination showed a well differentiated keratinising squamous cell carcinoma with numerous mitotic figures and many epithelial pearls. A thorough examination in search of a primary carcinoma of the lacrimal gland or the sinus, with invasion into the orbit, or an epithelial neoplasm elsewhere suggestive of metastatic disease into the choroid did not reveal any specific pathological findings. Thus the most probable origin of the tumour seems to be epithelium which had been misplaced during retinal detachment surgery and had subsequently undergone malignant transformation.

[Histological classification of uveal melanoma]. / Histologiczna klasyfikacja czerniaków naczyniówki.

Cytological classification of choroidal malignant melanomas recommended by WHO and based on the Callender classification (spindle A and B, mixed and epithelioid) is presented. Prognosis according to the histological types is discussed.

Congenital hypertrophy of the retinal pigment epithelium. Electron microscopic and morphometric observations.

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a well-circumscribed, flat, pigmented fundus lesion that is stable and generally nonprogressive. Light and electron microscopy and morphometric analysis was used to study a lesion with the clinical characteristics of CHRPE found in an eye enucleated for a posterior segment malignant melanoma. These studies showed that the lesion was composed of tall, maximally pigmented RPE cells that had a density 1.7 times greater than the density of the adjacent normal peripheral RPE. These observations suggested that cellular hyperplasia and hypertrophy may contribute to CHRPE. Ultraviolet fluorescence microscopy showed no autofluorescent granules of lipofuscin in the CHRPE, suggesting that the lesion's constituent cells lack the capacity to phagocytose and digest photoreceptor outer segments. Photoreceptor degeneration in the overlying retina consequent to this functional defect could be responsible for the localized visual field defects that typically occur in patients with CHRPE.

Differences in nuclear pore density among human choroidal melanoma cell types.

Two cases of mixed cell type choroidal melanoma were examined by means of conventional and freeze-fracture electron microscopy. Data on average nuclear pore density were readily collected from freeze-fracture replicas of spindle A, spindle B, and epithelioid cells. Highly significant (p less than 0.001) differences in pore densities were found among the three cell types. Pore density was lowest in spindle A cells, intermediate in spindle B cells, and highest in epithelioid cells. The possible relationship between nuclear pore density and nucleolar activity as well as the potential usefulness of this new finding as a prognostic indicator in cases of choroidal melanoma are discussed.

Bilateral choroidal neonatal neuroblastoma.

We treated a bilateral, well-differentiated neuroblastoma of the choroid in a patient who had congenital abdominal neuroblastoma. Although orbital metastasis of neuroblastoma is common, intraocular metastasis is not. In our patient, there was no amplification of the N-myc oncogene in the tumor of either eye. This is consistent with early-stage primary neuroblastoma. Histologically, the tumors were identical in each eye and well differentiated with Homer Wright rosettes; most neuroblastoma metastases have few rosettes and are composed of more undifferentiated, anaplastic cells. We believe that our patient had bilateral primary tumors and not metastatic tumors.

Massive fibrosis of extraocular muscles related to intraocular tumor.

A resin histological and ultrastructural study of 9 fibrotic extraocular muscles from 2 patients who underwent enucleation because of advanced intraocular malignant melanoma is reported. Total fibrosis of the extraocular muscles was evident in one case and extensive fibrosis in the other case. The patients did not suffer from congenital fibrosis syndrome. Ultrastructurally, the muscle tissue was replaced by collagen fibrils showing great variability of caliber.