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M N Burnier

Publications and source records attributed to M N Burnier.

At least 19 recordsLinked to original sources
PubMed2006

Identification of circulating malignant cells and its correlation with prognostic factors and treatment in uveal melanoma. A prospective longitudinal study.

PURPOSE: Most uveal melanoma patients (UMP) do not show evidence of metastases upon diagnosis. However, despite local tumour control, approximately 50% of them will develop metastases. These findings suggest that malignant cells may have already disseminated by the time of initial diagnosis. The purpose of the study was to detect circulating malignant cells (CMCs) in UMP and to correlate them with prognostic factors and therapy. METHODS: Nested reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect CMCs. In each UMP, blood was collected every 3 months. In each visit, 20 RT-PCR tests were performed. The date of diagnosis, largest tumour dimension, type, and date of treatment were obtained. RESULTS: A total of 30 UMP were enrolled. Five patients were enrolled at the time of diagnosis and 25 patients between 1 and 17 years following diagnosis. No UMP showed clinical evidence of metastasis. A total of 136 visits were registered, 1360 samples collected, and 2720 RT-PCRs performed. CMCs were identified in 29 patients in 119 visits (87.5%). However, in each visit, a low number of positive tests were recorded. CMCs were found in newly diagnosed, irradiated, enucleated, and observed patients regardless of tumour size and time period following treatment. CONCLUSIONS: Uveal melanoma (UM) is not a localized ocular disease. CMCs were recorded at initial diagnosis confirming the early metastatic nature of UM. CMCs were present following treatment, including enucleation, demonstrating that CMCs are capable of disseminating and surviving, possibly as micrometastasis, which would contribute to the pool of CMCs at a later stage. Systemic therapy should be evaluated.

Aged↗
PubMed2006

TGFBI gene mutations in Brazilian patients with corneal dystrophy.

PURPOSE: To investigate the transforming growth factor beta-induced gene (TGFBI) mutations in Brazilian patients with corneal dystrophy and to evaluate the phenotype-genotype correlation in these patients. METHODS: A total of 11 unrelated families were studied. The diagnosis of corneal dystrophy was based on clinical and histopathological findings. Genomic DNA was extracted from peripheral blood leucocytes, and exons 4 and 12 of the TGFBIgene were amplified by polymerase chain reaction followed by direct sequencing on both strands. RESULTS: Five different mutations in the TGFBIgene were found in the probands. We identified the following mutations: lattice corneal dystrophy--R124C and A546T; Reis-Bücklers corneal dystrophy--R555Q and R124L; granular corneal dystrophy--R555W and Avellino dystrophy--R555W. In three of the 11 studied families there was no mutation in exons 4 and 12. CONCLUSIONS: This is the first report of mutations in the TGFBIgene in a series of Brazilian patients with corneal dystrophy. The findings indicate that TGFBIgene screening should be considered in the diagnosis of corneal dystrophy.

Base Sequence↗
PubMed2006

The effect of a selective cyclooxygenase-2 (COX-2) inhibitor on the proliferation rate of retinoblastoma cell lines.

PURPOSE: To examine the effect of nepafenac, a selective cyclooxygenase-2 (COX-2) inhibitor, on the proliferation rate of two human retinoblastoma (Rb)cell lines. METHODS: Two human Rb cell lines (WERI-RB and Y79) were cultured. COX-2 expression in these cell lines was verified by immunocytochemical analysis of cytospin sections and Western blotting. An MTT-based proliferation assay was used to compare Rb cell growth with and without amfenac, the active metabolite of nepafenac. The averaged results per condition were recorded. The Student's t-test was used to compare results from the cells cultured with and without amfenac. RESULT: The Y79 cell line showed a higher proliferative rate than the WERI-RB cell line. Both cell lines were negative for COX-2 expression by immunocytochemical analysis; however, both cell lines were positive for COX-2 expression by Western blot. When amfenac was added to both of the cell lines, a statistically significant reduction in proliferation was observed in both cell lines. The two Rb cell lines were positive for COX-2 only in the Western blot, indicating that they probably express low levels of COX-2, which was undetectable by immunocytochemical analysis. CONCLUSION: The selective, anti-COX-2 molecule amfenac inhibited proliferation of both tested Rb cell lines. Further trials should be undertaken to study the effect of selective COX-2 inhibitors on Rb.

Blotting, Western↗
PubMed2005

Basal cell carcinoma of the eyelid in children: a report of three cases.

Basal cell carcinoma is the most common eyelid malignancy, accounting for approximately 90% of malignant eyelid tumours. Despite its prevalence in adults, it is extremely rare in children, and usually occurs in the setting of a known genetic defect or following radiotherapy treatment. We report three cases of de novo basal cell carcinoma in children. These children had no known genetic syndromes and had not undergone radiotherapy.

Adolescent↗
PubMed2005

Cost considerations of the new fixed combinations for glaucoma medical therapy.

OBJECTIVE: To compare the costs of the new fixed combinations for glaucoma medical therapy. METHODS: The studied drugs were: Cosopt (5-mL bottle), Combigan (5-mL bottle) and Xalacom (2.5-mL bottle). Five bottles of each drug were obtained from pharmacies, and the medications lot numbers were recorded. To calculate the drop volume, 10 drops and 1 mL of each bottle were weighed with a digital precision scale. Drop volume was calculated by the relation between volume and weight. The cost of each bottle of medication was determined from the average retail price in Canada. The prices were obtained in Canadian dollars (dollars). RESULTS: The drops of Cosopt (39.60 +/- 0.45 microL) were considerably larger than the drops of Combigan (33.75 +/- 0.60 microL) and Xalacom (30.87 +/- 0.37 microL). The average number of drops per millilitre varied from 25.25 +/- 0.29 (Cosopt) to 32.40 +/- 0.39 microL (Xalacom). Combigan presented the lowest daily cost (dollars 0.87 +/- 0.02) followed by Xalacom (dollars 1.09 +/- 0.01) and Cosopt (dollars 1.22 +/- 0.01). The average cost by year varied from dollars 316.75 +/- 5.59 (Combigan) to dollars 445.96 +/- 5.16 (Cosopt), with a total difference of dollars 129.21 per year of treatment. CONCLUSIONS: There was a statistically significant difference in average drop size and cost among the three studied drugs. Combigan presented the lowest daily cost followed by Xalacom and Cosopt.

Administration, Topical↗
PubMed2004

Accuracy of the clinical diagnosis of chalazion.

PURPOSE: A chalazion, localized lipogranulomatous inflammation of the eyelid, may simulate various eyelid lesions. This study was conducted to determine the accuracy of the clinical diagnosis of chalazion and demonstrate the importance of histopathological confirmation of the diagnosis. METHODS: Histopathological diagnoses of 1060 cases with the clinical diagnosis of chalazion, submitted to the Henry C Witelson Ophthalmic Pathology Laboratory and Registry between September 1993 and December 2001, were retrospectively evaluated. Discrepancies between clinical and histopathological diagnoses were classified. RESULTS: A total of 1033 (97.4%) of the 1060 cases were clinically diagnosed as primary and the remaining 27 (2.6%) as recurrent chalazions. Agreement was noted between clinical and histopathological diagnoses in 992 (93.6%) cases. Of the 68 (6.4%) clinically misdiagnosed cases, 15 (1.4%) were found to be malignant, two (0.2%) premalignant, and 51 (4.8%) benign conditions. Sebaceous cell carcinoma was the most commonly missed malignancy (12 cases, 1.1%) followed by basal cell carcinoma (three cases, 0.3%). Premalignant lesions, which masqueraded as chalazion, were chronic inflammation with cellular atypia and mitotic figures (two cases, 0.2%). Of these 17 cases with premalignant and malignant histopathologies, only six (35.3%) had a clinical diagnosis of recurrent chalazion, whereas the others (64.7%) were primary cases. Of the various benign conditions that were misdiagnosed as chalazion, different types of chronic inflammation (24 cases, 2.2%) were the most frequent. CONCLUSIONS: A number of different benign, premalignant, and malignant conditions may clinically masquerade as a chalazion. Delayed diagnosis and treatment of sebaceous cell carcinoma, which is the most frequently missed malignancy, may be life threatening for the patient. Therefore, all chalazion specimens, primary or recurrent, should be submitted for histopathological examination.

Adenocarcinoma, Sebaceous↗
PubMed2001

Cytomorphometric parameters and the metastatic potential of cutaneous and uveal melanoma: a comparison with prognostic factors.

The Mean of the Ten Largest Nuclei (MTLN1) is one of the most important prognostic factors in uveal malignant melanoma. This study was performed to investigate the applicability of nuclear and nucleolar measurements as a prognostic factor for cutaneous melanoma. A routine light microscope (Carl Zeiss: Axiophot EL-Einnsatz; #451888) at 640 times magnification with a Micrometer Eye Piece (Carl Zeiss: #444034) was used to evaluate the correlation of MTLN1 and Mean of Ten Largest Nuclei (MTLN) with the occurrence of metastasis in 58 primary cutaneous melanoma. For uveal melanoma, cytologic classification was used for comparison. Prognostic value was determined by univariate and multivariate linear regression analysis. MTLN1 was the only significant factor for uveal melanoma (p = 0.05). For cutaneous melanoma, all factors were significantly associated with disease progression. MTLN1 was the only one to remain significant (p + 0.027) in multivariate linear regression analysis. Nuclear and nucleolar morphometry are significant prognostic factors for uveal and cutaneous melanoma.

Humans↗
PubMed1998

Neuro-ophthalmic findings in progressive multifocal leukoencephalopathy.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a demyelinating disorder of the central nervous system found in immunodeficient patients, most frequently now in those infected with HIV. It may represent the initial manifestation of HIV infection. Since the central visual pathways may be affected, a variety of neuro-ophthalmic signs and symptoms can manifest. We studied the clinical, radiographic and histopathological characteristics of patients with PML. METHODS: The charts of 13 patients in whom PML was diagnosed in the Neuro-AIDS clinic at the Montreal Neurological Institute between November 1987 and March 1995 were reviewed. The diagnosis of PML was established by characteristic clinical features together with typical computed tomographic or magnetic resonance imaging findings, such as nonenhancing low-density (on computed tomography) or hyperintense (on T2-weighted magnetic resonance imaging) white-matter lesions, without mass effect. Neuro-ophthalmic findings were based on clinical examination by an ophthalmologist, neuro-ophthalmologist or neurologist. Tissue for pathological examination was obtained by biopsy in one case and at postmortem study in a second case. RESULTS: The most common finding was homonymous hemianopia, in five patients (38%). Other features included nystagmus (in two patients), diplopia with cranial nerve palsy (in one) and cortical blindness (in one). One of the patients exhibited involvement of the brain stem, a site not usually affected by this demyelinating process. INTERPRETATION: The diagnosis of PML should be considered in immunocompromised patients with neuro-ophthalmic findings, particularly those with homonymous hemianopia.

AIDS Dementia Complex↗
PubMed1997

Primary choroidal melanoma in a patient with previous cutaneous melanoma.

A 67-year-old woman with a history of a skin melanoma that was excised 7 years previously had a 6-month history of decreased vision in her right eye. A choroidal melanoma was diagnosed clinically, and the eye was enucleated. The results of a histopathological examination revealed a primary uveal melanoma. Slides of the skin melanoma were obtained, and the initial diagnosis was confirmed. In an attempt to illustrate a biological difference between the 2 melanomas, immunohistochemical studies were performed on sections of the 2 specimens using S-100 protein, HMB-45, and S-100-beta. Primary cutaneous and choroidal melanomas appearing in a patient with no predisposition are rare; this is believed to be only the fifth such case reported in the literature.

Aged↗
PubMed1997

Thymic carcinoma metastatic to the orbit.

PURPOSE: To report a case of small cell carcinoma of the thymus metastatic to the orbit. METHODS: At age 37 years, a man who had been previously diagnosed and treated for small cell carcinoma of the thymus was initially examined for vertical diplopia and left proptosis. Computed tomographic scan disclosed a soft tissue mass in the superior aspect of the left orbit. A fine-needle aspiration biopsy of the mass was performed and submitted for cytopathologic examination. RESULT: The cytopathology and immunopathology disclosed malignant cells consistent with metastatic small cell thymic carcinoma. CONCLUSION: This is the first reported case of a primary thymus gland tumor metastatic to the orbit.

Adult↗
PubMed1997

Uveal melanoma. Comparison of the prognostic value of fibrovascular loops, mean of the ten largest nucleoli, cell type, and tumor size.

PURPOSE: This study was performed to determine the prognostic significance of the presence of loops defined as periodic acid-Schiff-positive fibrovascular septa that completely surround lobules of tumor cells in cases of uveal melanoma. METHODS: The presence of loops was evaluated using an ordinary light microscope and routinely stained periodic acid-Schiff and hematoxylin sections from 496 posterior uveal melanomas without knowledge of the follow-up data on the patient. RESULTS: At 15 years, survival decreased from 67.5% to 33.8% when complete loops were present. Univariate Cox regression analysis indicated that the presence of loops was an indicator of poor outcome, and was better than age but not as good as the mean diameter of the largest nucleoli, cell type, or tumor size. CONCLUSIONS: The presence of loops, as evaluated in this study, was not as strong an indicator of poor outcome as were loops assessed in a previous study of 234 cases from another laboratory. The authors suspect this difference may be due to their only using routinely stained sections without a green filter, as was used in previously reported studies. The authors description of loops does not require any special equipment and gives sufficiently useful results to justify its inclusion by the pathologist in reports of such specimens. A description of vascular loops should be added to the use of the modified Callender cell type, tumor dimensions, mitotic count, extraocular extension, and lymphocytic infiltration in the final pathologic report.

Cell Division↗
PubMed1997

Orbital granulocytic sarcoma.

AIM: Orbital granulocytic sarcoma is a localised tumour composed of cells of myeloid origin. Histological diagnosis can be difficult in patients with poorly differentiated orbital tumours and no evidence of systemic leukaemia. The naphthol AS-D chloracetate esterase (Leder stain) and immunohistochemical stains for lysozyme and MAC387 were used to determine the staining characteristics of these tumours. A case series of seven patients with orbital granulocytic sarcoma is presented. METHODS: Seven patients with orbital granulocytic sarcoma were studied. Haematoxylin and eosin, Leder, and lysozyme stained sections were available in seven cases. Unstained formalin fixed paraffin embedded sections of seven cases were available for immunohistochemical evaluation using the avidin-biotin-complex technique for MAC387. RESULTS: The mean age of presentation of the orbital tumour was 8.8 years. Four patients presented with an orbital tumour before any systemic manifestations of leukaemia. In two cases the diagnosis of the orbital tumour and systemic leukaemia was made simultaneously. There was one case of established systemic myeloid leukaemia in remission with the subsequent development of orbital granulocytic sarcoma. Six of seven cases (86%) were positive for the Leder stain. Five of seven cases (71%) showed positive immunoreactivity with lysozyme. The immunohistochemical stain for MAC387 was positive in all seven cases (100%) including one case that was negative for both lysozyme and Leder stains. CONCLUSIONS: Orbital granulocytic sarcoma is a tumour that affects children and can present with rapidly progressive proptosis. This tumour may develop before, during, or after the occurrence of systemic leukaemia. The combination of Leder and lysozyme stains is useful in the diagnosis of orbital granulocytic sarcoma. MAC387 may be a more reliable marker for orbital granulocytic sarcoma.

Acute Disease↗
PubMed1997

Immunohistochemical expression of S-100 beta in choroidal melanomas.

OBJECTIVE: To investigate the expressivity of S-100 beta antibodies in choroidal melanomas and to compare it with that of S-100 protein and HMB-45. DESIGN: Twenty-seven choroidal melanoma specimens obtained from the McGill University Ophthalmic Pathology Registry were classified as spindle cell, epithelioid cell or mixed-cell type. Immunohistochemistry was performed using the standard peroxidase-antiperoxidase technique with monoclonal HMB-45, polyclonal S-100, polyclonal S-100 beta and monoclonal S-100 alpha beta antibodies in formalin-fixed, paraffin-embedded sections. OUTCOME MEASURE: Intensity of immunoreaction. The result was considered positive when at least five focal areas of stained cells were observed within the tumour. RESULTS: All 27 tumours were positive for HMB-45, 19 (70%) for S-100, 23 (85%) for S-100 beta, and 21 (78%) for S-100 alpha beta. No correlation was found between the intensity of the immunoreaction and cell classification. CONCLUSIONS: HMB-45 is the most reliable marker for choroidal melanomas. S-100 beta is a more sensitive marker than S-100 for choroidal melanomas regardless of cell type. Contrary to previous reports, S-100 beta should not be considered a useful immunomarker to differentiate between primary choroidal melanoma and cutaneous melanoma metastatic to the choroid.

Antibodies, Monoclonal↗