1/6. Primary ocular Epstein-Barr virus-associated non-Hodgkin's lymphoma in a patient with AIDS: a clinicopathologic report.OBJECTIVE: To report an unusual case of chronic multifocal chorioretinitis with vitritis in a patient with acquired immunodeficiency syndrome (AIDS) that was resistant to antiviral and antitoxoplasmic medication and required a retinal biopsy for definitive diagnosis. methods: Vitreous biopsy, pars plana vitrectomy, and retinal biopsy were performed. The vitreous biopsy material was sent for bacterial, fungal, and viral culture, and the vitreous cassette was sent for cytology. The retinal biopsy material was divided and sent for polymerase chain reaction testing for toxoplasmosis and virology and pathologic tissue analysis. RESULTS: Vitreous cytology showed a mixed population of lymphocytes and histiocytes, but all other microbiologic and virologic studies were negative. Tissue analysis revealed an infiltrate of atypical mononuclear cells extending from the inner limiting membrane through the outer plexiform layer characteristic of a B cell, non-Hodgkin's lymphoma of the central nervous system (NHL-CNS). in situ hybridization for the Epstein-Barr virus (EBV) was positive. An extensive systemic evaluation did not show evidence of extraocular tumor. CONCLUSION: Although rare, primary ocular NHL-CNS can be seen in patients with AIDS, and its clinical presentation often closely resembles other disorders. To our knowledge, this case represents the first ocular NHL in which EBV is shown to be associated.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/6. Multifocal osteosarcoma as second tumor after childhood retinoblastoma.We present a case of multifocal osteosarcoma (MFOS) arising 11.5 years after successful treatment of bilateral retinoblastoma. The clinical, imaging and pathological findings at onset, after therapy, and during follow-up are described. Fluorescent in situ hybridization did not reveal a deletion of the RB-1 retinoblastoma gene, although the presence of an inactivating mutation invisible to this method cannot be ruled out. The MFOS may have been a second multifocal tumor associated with the original retinoblastoma or a post-irradiation sarcoma with extensive metastases.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/6. Trilateral retinoblastoma variant indicative of the relevance of the retinoblastoma tumor-suppressor pathway to medulloblastomas in humans.Results of recent studies have led investigators to suggest that the retinoblastoma tumor-suppressor (rb) gene plays an underappreciated role in the genesis of brain tumors. Such tumors cause significant rates of mortality in children suffering from hereditary retinoblastoma. It has been assumed that the pineal gland, which is ontogenetically related to the retina, accounts for the intracranial origin of these trilateral neoplasms. To address this issue, the authors describe an unusual trilateral retinoblastoma variant. The authors provide a detailed clinicopathological correlation by describing the case of a child with bilateral retinoblastoma who died of a medulloblastoma. The intraocular and intracranial neoplasms were characterized by performing detailed imaging, histopathological, and postmortem studies. karyotype analysis and fluorescence in situ hybridization were used to define the chromosomal defect carried by the patient and members of her family. An insertion of the q12.3q21.3 segment of chromosome 13 into chromosome 18 at band q23 was identified in members of the patient's family. This translocation was unbalanced in the proband. The intraocular and cerebellar neoplasms were found to be separate primary neoplasms. Furthermore, the pineal gland was normal and the cerebellar neoplasm arose within the vermis as a medulloblastoma. Finally, the two neoplasms had different and characteristically identifiable cytolological and immunohistochemical profiles. The findings of the present study, taken together with those of recent molecular and transgenic studies, support the emerging concept that rb inactivation is not restricted to central nervous system regions of photoreceptor lineage and that inactivation of this tumor suppressor pathway may be relevant to the determination of etiological factors leading to medulloblastoma in humans.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/6. microdissection combined with the polymerase chain reaction to identify potentiating viral co-infection in patients with hiv/AIDS with ocular infection.BACKGROUND: In the presence of several coexisting infections, superimposed tissue necrosis or tissue metaplasia, it may be difficult to recognize standard histologic morphology on hematoxylin-eosin slides. Tissue microdissection combined with the polymerase chain reaction (PCR-MD) offers the advantages of high specificity and relative speed. The objective of this study was to describe the use of PCR-MD in identifying potentiating viral co-infection in patients with hiv/AIDS with retinitis and choroiditis. methods: Eyes from two patients with hiv/AIDS with several ocular infections were studied by a variety of techniques, including standard histologic examination, immunochemistry, electron microscopy and in situ hybridization. PCR-MD was used to identify coexisting viral infections. RESULTS: Histologic examination showed cytomegalovirus retinitis in both cases. Use of PCR-MD allowed the identification of Epstein-Barr virus within a zone of fulminant varicella-zoster virus retinitis in one patient. PCR-MD confirmed the presence of human herpesvirus 8 in the second patient, who had ocular lymphoma. INTERPRETATION: PCR-MD can be used to demonstrate coexisting viral infection in ocular specimens from patients with unusually fulminant courses. Co-infections may contribute to the observed clinical course and should be considered in patients with rapid progression or unusual presentation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/6. Interstitial deletion of 13q and a 13;x chromosome translocation results in partial trisomy 13 and bilateral retinoblastoma.BACKGROUND: Abnormalities of chromosome 13 have been associated with bilateral retinoblastoma. Deletion of a retinoblastoma gene is a common primary mechanism. Other abnormalities are more rare. To our knowledge, a balanced translocation of the long arms of the X and 13 chromosomes associated with bilateral retinoblastoma has been reported five times. We report an unbalanced X;13 translocation resulting in partial trisomy 13 and an interstitial deletion of an RB locus. methods: Case report. RESULTS: A 19-month-old child presented with seizures to the emergency department. A CT scan revealed bilateral intraocular calcification, and retinoblastoma (RB) was confirmed with an ophthalmic exam. Abnormal facies and developmental delay were noted. A partial trisomy derived from the translocation of X;13 was observed in both bone marrow and peripheral blood cells. fluorescence in-situ hybridization (FISH) studies confirmed triplication of a region on the q arm of chromosome 13 spanning the RB locus. One of the normal chromosome 13 homologues had an interstitial deletion of the RB locus since no signal was observed for the RB-1 probe despite the visible presence of the 13q14 region. Additional evidence of the interstitial deletion is supported by the typical facial features and developmental delay found. Presumably, the translocated X underwent X inactivation precluding systemic features typically observed in trisomy 13. Parental karyotypes were normal. The chromosomal abnormality was a de-novo constitutional event. CONCLUSIONS: Only two RB loci were present in this patient despite triplication of 13q. The third locus was deleted. We believe that the second locus was not expressed due to X inactivation of the RB gene on the der(X)t(Xq:13q) chromosome. The emergence of bilateral retinoblastoma points towards lack of heterozygosity at the third and last remaining RB loci in tumor cells. To our knowledge, an unbalanced translocation resulting in partial trisomy 13 with retinoblastoma has not been previously reported.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/6. retinoblastoma, pinealoma, and mild overgrowth in a boy with a deletion of RB1 and neighbor genes on chromosome 13q14.We report on a 10-year-old boy with a normal karyotype and a chromosome 13q14 deletion of the retinoblastoma gene (RB1) by fluorescence in situ hybridization (FISH). He showed subtle signs of overgrowth, including macrocephaly, hepatomegaly, and inguinal hernia. The boy also had cryptorchism and mild developmental delay. In his first months of life, variant Wiedemann-Beckwith syndrome was tentatively suspected and he was included in a careful tumor prevention program. At the age of 11 months, bifocal retinoblastoma of the left eye was diagnosed. pinealoma was suspected at the age of 19 months and was removed by neurosurgery at the age of 29 months. At 4 years and 4 months, the deletion of the RB1 gene was suspected on clinical grounds and was diagnosed by FISH and molecular studies. At that time, he was a near-normal healthy playful kindergarten child, height 107 cm (-0.3 SD), OFC 52.5 cm ( 0.8 SD), developmental age 3-3.5 years. The combination of retinoblastoma, pinealoma, and deletion of the RB1 gene diagnosed by FISH has not been reported previously. The deletion spans at least 370-420 kb in size and is predicted to include proximal and distal neighbor genes. This report may assist in establishing the clinical signs of the contiguous gene syndrome at the RB1 locus on 13q14.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |