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Biomedical subjects

O A Jensen

Publications and source records attributed to O A Jensen.

At least 19 recordsLinked to original sources
PubMed2000

Immunohistochemical diagnosis of malignant melanoma of the conjunctiva and uvea: comparison of the novel antibody against melan-A with S100 protein and HMB-45.

A novel antibody A103, which recognizes melan-A/MART-1, has been found to be more sensitive than the antibody HMB-45, which recognizes gp100, in melanocytic lesions of the skin and might therefore also be useful in the diagnosis of uveal and conjunctival melanocytic lesions. In this study we compared the staining characteristics of anti-melan-A, anti-S100 protein and HMB-45 in 13 conjunctival, 11 iris and 37 ciliary and choroidal malignant melanomas. The ciliary and choroidal melanomas comprised 13 spindle cell (10 spindle B and three spindle A), 14 mixed cell and 10 epithelioid cell tumours. In the conjunctival melanomas the diagnostic sensitivity was 100% for anti-S100 and anti-melan-A and 85% for HMB-45. In the iris melanomas the sensitivity was 100% for anti-S100 and anti-melan-A and 55% for HMB-45. A high staining intensity of anti-melan-A was particularly noticed in iris melanomas. In the choroidal malignant melanomas, the spindle cell and mixed cell types showed a sensitivity of only 69-79% with all three antibodies. In the epithelioid cell type the sensitivity was 80% for anti-S100 and 100% for HMB-45 and anti-melan-A. In conclusion, anti-melan-A was found to be a useful addition to antibody panels for ocular melanocytic lesions. Anti-melan-A has a higher sensitivity than HMB-45 in conjunctival and iris melanomas, but the sensitivity is similar to HMB-45 in choroidal melanomas. Anti-melan-A stains in a very similar pattern to anti-S100, but the staining intensity of anti-melan-A is higher than that of anti-S100 in iris melanoma.

Antibodies, Monoclonal↗
PubMed1998

[Conjunctival nevi in Denmark 1960-1980. A 21-year follow-up].

The clinicopathological characteristics of 343 naevi of the conjunctiva were studied. A significant increase in the number of naevi excised per year was observed. This may have been caused by an increased exposure to actinic rays. An approximately even distribution was found between the three main locations: caruncle, limbal area and eye ball. Intrastromal naevi were excised at a higher median age than compound naevi, and the lowest median age at excision was for junction naevi, which is in accordance with the known histopathological nature of naevi. Recurrence occurred in nine patients (2.7%), and one had transformed into a malignant melanoma. Eight of the recurring naevi were located in the limbal area. Eight of the nine patients were women, suggesting hormonal factors as a possible cause. Recommendations for the handling of conjunctival naevi are given, based on the present findings and on previous reports.

Adolescent↗
PubMed1997

Transvitreal retino-choroidal biopsy of suspected malignant lesions of the choroid. Follow-up of cases over 7 years.

The cases of transvitreal retino-choroidal (TVRC) biopsy from 1987 to 1994 were assembled in order to examine the efficiency, complications and risks to patients. Of 92 biopsies 91 had sufficient material for diagnosis. Eighty (87%) contained malignant tissue, whereas 10 cases were negative and two unsuccessful. Tumours of appropriate size were treated by brachytherapy. Twenty-three large tumours were enucleated primarily. Eight irradiated eyes had to be removed. In 31 cases, therefore, it was possible to examine the whole tumour for changes caused by the biopsy and to compare the typing of the biopsy with that of the whole tumour. In the irradiated eyes histologically viable tumour cells remained mostly in the inner part of the tumour. Scleral necrosis was not found. The technique used appears to be safe. Histological verification is highly recommended before any conservative therapy, inter alia to obtain true statistics of therapeutic results.

Adolescent↗
PubMed1996

Metastatic uveal melanoma. A morphologic and immunohistochemical analysis.

BACKGROUND: Uveal melanoma often metastasizes late and preferentially to the liver, in contrast to cutaneous melanoma. The objective of the current study was to evaluate the histopathologic and immunohistochemical changes in primary uveal melanomas and their corresponding metastases. METHODS: The morphology and immunohistochemical reactivity for the melanoma-associated antibodies HMB-45, S-100 protein, and NKI-C3 were assessed for 29 primary uveal melanomas and their corresponding metastatses. RESULTS: A significant difference in cell type of the primary and the metastatic uveal melanoma was found (P = 0.0001). The metastases derived from the 29 patient's revealed 82.5% epithelioid or nonclassifiable cells. Positive staining of the primary uvea melanomas and their metastases was found to be 93% and 91%, respectively, for HMB-45, 80% and 66%, respectively, for S-100, and 56% and 71%, respectively, for NKI-C3. CONCLUSIONS: Metastases of uveal melanomas are comprised of a higher grade of malignant cell types. Nonclassifiable cells can be observed in 40% of metastatic lesions. In the current study, HMB-45 proved to be the most sensitive immunohistochemical marker in the analysis of metastatic uveal melanoma and should be used as part of a panel of monoclonal antibodies in the analysis of any metastatic tumor of unknown origin.

Antigens, Neoplasm↗
PubMed1996

Malignant melanoma of the conjunctiva: occurrence and survival following surgery and radiotherapy in a Danish population.

PURPOSE: To describe patient characteristics, risk of recurrence, and survival in patients with premalignant and malignant melanocytic lesions of the conjunctiva. METHODS: In a retrospective study, 55 cases with a minimum follow-up of 10 years were reviewed. RESULTS: The actuarial 5-and 10-year survival rates were 86% (95% Cl: 76-96%) and 73% (95% Cl: 60-87%) respectively. The 5-year risk of local recurrence was 35% (95% Cl: 21-49%), and the 10-year risk was 43% (95% Cl: 28-58%). Primary acquired melanosis with atypia was the first manifestation in 13 cases, malignant melanoma in 42 cases. No significant difference in survival and recurrence was found between the two groups or by gender, location of primary lesion, histological characteristics, or extent of surgical procedure. A minimum incidence of 0.052 cases a year per 100 000 in Denmark was calculated. CONCLUSION: The results are estimated to represent a nationwide sample of patients. No prognostic factors of significance were identified.

Adolescent↗
PubMed1996

Cranio-orbital teratoma.

A new-born baby presented with a large, rapidly growing tumour. The tumour involved the right orbit, the anterior half of the right intracranial space and extended through the skull of the temporal region. The proptotic eye ruptured due to exposure. The tumour was extirpated when the patient was 12 days old. A large recurrence was extirpated two months later. The tumour was firmly bound to the medial aspect of the superior orbital fissure which probably was the location of origin of the tumour. Based on the size of the intracranial-and the orbital part of the tumour, it was classified as a secondary orbital teratoma. The tumour was macroscopically composed of cystic and solid areas. Microscopically it was seen to be a benign teratoma with tissue from all three germinal layers.

Brain Neoplasms↗
PubMed1996

Conjunctival naevi in Denmark 1960-1980. A 21-year follow-up study.

The clinicopathological characteristics of 343 naevi of the conjunctiva were studied. A significant increase in the number of naevi excised per annum was observed. This may have been caused by an increased exposure to actinic rays. Approximately even distribution in the three main locations: caruncle, limbal area and eyeball, was found. Intrastromal naevi were excised at a higher median age than compound naevi, and the lowest observed median age at excision was for junction naevi, which is in accordance with the known histopathological nature of naevi. Recurrence occurred in nine patients (2.7%), and one transformed to a malignant melanoma. Eight of the recurring naevi were located in the limbal area. Eight of the nine patients were women, suggesting hormonal factors as a possible cause. Recommendations for the handling of conjunctival naevi are given, based on the present findings and on previous reports.

Adolescent↗
PubMed1995

Neural cell adhesion molecule distribution in primary and metastatic uveal melanoma.

Tumor cell adhesion, detachment, and aggregation play an important part in tumor invasion and metastasis, and a variety of cell adhesion molecules have been found on tumor cells. Cell adhesion molecules, including those of the immunoglobulin superfamily, are associated with the development of metastatic behavior in cutaneous melanomas. The neural cell adhesion molecule (NCAM) belongs to this family. To investigate its possible role in the development metastatic behavior of uveal melanomas, the authors studied immunohistochemically the expression of NCAM by using an antibody that recognizes all three major isoforms of NCAM and an antibody that recognizes the HNK-1 epitope present on some isoforms of NCAM. The authors studied 32 primary uveal melanomas from 32 patients (among these, 12 were rapidly metastasizing and 16 slowly metastasizing) and 29 metastases from 19 patients. From 13 patients the primary, as well as the metastatic, tumors were available. With one exception, all HNK-1 positive primary and metastatic tumors were also positive for NCAM. NCAM was significantly more expressed in aggressive, rapidly metastasizing primary tumors (P = .02 and .04, respectively) and in metastases. HNK-1 was significantly (P = .04) more expressed in larger tumors. In liver metastases HNK-1 immunoreactivity was significantly (P = .005) less frequently expressed than NCAM. Therefore, NCAM isoforms that lack the HNK-1 epitope might play a role in the organ specific metastatic behavior of uveal melanomas.

Antibodies, Monoclonal↗
PubMed1994

Intraocular T-cell lymphoma mimicking a ring melanoma. First manifestation of systemic disease. Report of a case and survey of the literature.

A case is presented of an intraocular T-cell lymphoma mimicking a ring melanoma of the iris and being the first manifestation of systemic disease. A 51-year-old woman was referred with an anterior uveitis, initially presenting as a granulomatous iritis. Nodules had developed in the circumference and the lesion now imitated a malignant melanoma of the iris, which was also the diagnosis from a biopsy specimen with routine staining. Clinical, haematological and serological examination revealed no other symptoms or signs. Lymphocytic markers applied to the biopsy specimen and to the enucleated eye revealed a highly malignant T-cell lymphoma infiltrating the iris, ciliary body, anterior choroid, retina and the adjacent vitreous body. Further examination later showed T-cell lymphoma in the bone marrow, the only other organ involved. The patient died in a leukaemic phase about 1 year after the first admission. Previous cases of T-cell lymphoma with ocular involvement are reviewed.

Ciliary Body↗
PubMed1993

Prognostic value of nucleolar size and size pleomorphism in choroidal melanomas.

Morphometric estimates of nucleolar size have been shown to possess a high prognostic value in patients with uveal melanomas. The authors investigated various quantitative estimators of the mean size and pleomorphism of nucleoli in choroidal melanomas from a consecutive series of 95 Danish patients treated solely by enucleation of the melanoma-bearing eye in the period from 1977 to 1979. The independent prognostic value of the quantitative histopathological variables was evaluated using multivariate Cox analysis. Apart from patient data and information about tumor extent, histological type of melanoma, and largest macroscopic tumor dimension (LTD), the following histomorphometric estimates were obtained: mean diameter of the 10 largest nucleoli (MLN), point-sampled mean nucleolar profile area (nucleolar ao) and the associated standard deviation of nucleolar ao, the volume-weighted mean nucleolar volume (nucleolar vv), and associated variance and relative variance of nucleolar volume (nucleolar Varv(v) and nucleolar CVv(v), respectively). The intra-observer reproducibility of estimates of nucleolar vv was tested in 20 cases and found acceptable (r = 0.84, 2p = 3.6.10(-6)). Correlation analysis indicated that estimates of nucleolar vv and nucleolar Varv(v) are identical in choroidal melanomas, except for a scaling factor. There were no differences of the grouped means of histomorphometric estimates in choroidal melanomas that showed intra- or extra-ocular extension (2p > 0.13). LTD was of the same magnitude in all histological types of melanoma (2p = 0.69). Estimates of nucleolar vv and associated estimates of nucleolar volume pleomorphism were increased in melanomas of the mixed and epitheloid cell type (2p < 0.005). Single factor analyses showed that all quantitative histopathological variables were of prognostic value in the studied patients, in addition to the histological type of tumor. However, using multivariate analysis, only estimates of LTD, MLN, nucleolar vv, and of nucleolar volume pleomorphism had independent prognostic value.

Cell Nucleolus↗
PubMed1992

Hepatocellular carcinoma associated with arteriohepatic dysplasia in a 4-year-old girl.

Hepatocellular carcinoma and obliterated hepatic bile duct were found at postmortem examination in a 4-year-old girl with arteriohepatic dysplasia (Alagille's syndrome). AFP level was extremely high. Liver cirrhosis was present on percutaneous needle biopsy 9 months before she succumbed in progressive liver failure. Episodes of repeated gastrointestinal, life-threatening hemorrhages occurred during the last 6 months of her life. Histopathologic findings of the eyes were documented at autopsy.

Alagille Syndrome↗
PubMed1992

[Choroid melanoma. A retrospective randomized comparative study of ruthenium irradiation vs enucleation].

A randomized retrospective study concerning survival of Ruthenium treatment and enucleation in melanoma patients has been performed. For 112 patients from Hamburg who underwent Ruthenium therapy individual match partners were selected in Copenhagen where during the same period of time enucleation was the standard procedure. Selection took place concerning patient's age and sex at the time of treatment, initial tumor volume and the time of treatment. The present status of the patients was not known during the selection process. During the observation time of 12 years there was a survival rate after irradiation of 77.9% and after enucleation of 78.6%. Cox' regression disclosed a coefficient of 0.049 with a standard aviation of 0.293 and a P-value of 0.867. All parameters were showing no statistical difference between Ruthenium treated and enucleated patients. The survival rate in males was 69.2%, female patients 87.2%. For male patients there was a 2,4-fold higher risk to develop metastasis compared with female patients. Patient's age at the time of treatment correlated significantly with the prognosis. There was an increase in mortality risk by factor 1.4 per decade.

Aged↗
PubMed1990

Melanotic schwannoma of the orbit. Immunohistochemical and ultrastructural study of a case and survey of the literature.

Light microscopical, immunohistochemical and ultrastructural study of a case of melanotic (pigmented) schwannoma in the left orbit of a 22-year-old man is presented. The tumour caused exophthalmus for three months and was located under the eyeball. Partial removal resulted in recurrence after three years. The recurrent tumour with extension to the nasal cavity and maxillary sinus was extirpated without loss of vision, and a year later the patient was without symptoms. The tumour tissue was Fontana positive, could be bleached, and showed immunoreactivity for S-100, vimentin and HMB 45. Ultrastructurally, the tumour cells, particularly the pigment loaded cells, showed a varying amount of basal lamina at the surface, melanosomes in varying stages of melanization, fine cytoplasmic filaments and micropinocytotic vesicles. Survey of the literature and discussion of the melanogenesis in Schwann's cells are presented.

Adult↗
PubMed1989

Transvitreal retinochoroidal biopsy.

Biopsies from retina and/or choroid were performed through a transvitreal approach in 14 patients during the 2-year period 1984-1986. A 20-gauge fine needle was used. The transvitreal approach was chosen because exact location of the biopsy could be documented by video recording and/or by photography. The needle was guided either by a stereotactic micromanipulator or by hand. Immediately after biopsy laser burns were placed around the biopsy hole. Light microscopical and, in selected cases, transmission electron microscopical examination of the material obtained showed malignant melanoma, choroidal haemorrhage, leukaemic infiltration of the choroid, intraretinal fibrosis in detached retina, atrophic retina after vasculitis and malignant lymphoma of the uvea. More than 2 years after biopsy, no retinal detachment due to the biopsy or any tumour-seeding has been observed. Two cases of vitreous haemorrhage cleared spontaneously. No visual impairment was related to the biopsies.

Adolescent↗
PubMed1989

Conjunctival cell glycoprotein pattern of healthy persons and of patients with primary Sjögren's syndrome--light microscopical investigation using lectin probes.

Formalin-fixed biopsies of conjunctival tissue from the lower fornix of 10 healthy persons and of 10 patients with primary Sjögren's syndrome (primary SS) were examined by light microscopy. Deparaffinized, rehydrated sections of 5 microns were incubated overnight, each with one of 15 different biotinylated lectins. Bound lectins were visualized using avidin-HRP-substrate complexes. Five lectins did not bind to conjunctival cells, and further six lectins bound in an unspecific manner to conjunctival cells of both healthy persons and of primary SS patients. Jacalin lectin bound selectively to goblet cells of all specimens. Peanut agglutinin (PNA) and wheat germ agglutinin (WGA) bound significantly stronger to basal conjunctival epithelial cells of patients with primary SS. This binding pattern may be of diagnostic value.

Adult↗