1/56. Well-differentiated mucinous carcinoma of the ovary and a coexisting brenner tumor both exhibit amplification of 12q14-21 by comparative genomic hybridization.Although the coexistence of mucinous ovarian neoplasms and Brenner tumors is well established, the histogenesis and developmental relationship between the two remain unknown. We used comparative genomic hybridization to analyze two such tumors occurring simultaneously, one in each ovary, in a patient. Amplification of 12q14-21 sequences was found in both tumors; in addition, both tumors also had other, different changes, four identified in the brenner tumor and six in the mucinous carcinoma. The occurrence of the same genetic alteration in both tumors in this woman suggests that the mucinous carcinoma and brenner tumor may be clonally related, i.e., one arose from the other by means of metastatic spreading of transformed cells from one ovary to the other. An alternative explanation is that some unknown, putative tumorigenic agent induced similar and synchronous pathogenetic changes in the epithelium of both ovaries. The phenotypic differences between the tumors are presumably attributable to the other unique genetic abnormalities identified in both tumor types.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/56. Large cell transformation of sezary syndrome. A conventional and molecular cytogenetic study.Hyperdiploidy sometimes is found in mycosis fungoides-sezary syndrome, but its diagnostic significance remains undefined. We report an unusual case of sezary syndrome manifesting with leukemic large cell transformation. Conventional karyotypic analysis showed the presence of a near-tetraploid neoplastic clone. With dual-color cytometric analysis, we showed that the large Sezary cells were near-tetraploid with a dna index of 1.86, thereby demonstrating a direct relationship between cell size and ploidy. comparative genomic hybridization further showed chromosomal imbalances that were not revealed on conventional karyotyping. Our findings suggest that hyperdiploidy may be a marker of large cell transformation, so that when this karyotypic abnormality is found in mycosis fungoides-sezary syndrome, a search for such a complication is indicated.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
3/56. p53 intronic point mutation, aberrant splicing and telomeric associations in a case of B-chronic lymphocytic leukaemia.We report a case of chronic lymphocytic leukaemia (CLL) with telomeric associations and a p53 intronic point mutation. Karyotypic analysis revealed clonal and non-clonal telomeric associations, accompanied by clonal cytogenetic abnormalities and also in isolation. The p53 mutation, which occurred at the invariant base pair -2 of the splice acceptor site in intron 7 resulted in the abolition of correct splicing of exon 7 to exon 8. Multiple aberrant splice products were characterized, all of which differed from wildtype in the dna binding domain. fluorescence in situ hybridization demonstrated that the clone retained two copies of the p53 gene and wild-type p53 transcript was detected on cloning of reverse transcriptase polymerase chain reaction (RT-PCR) product, indicating that one wild-type allele remained. However, a plasmid clone with correct splicing at the exon 7/8 boundary, but with a 21 bp deletion in exon 8, was also found at low frequency. This finding indicates clonal evolution, resulting in complete loss of wild-type p53. The intronic point mutation was not present in dna extracted from cervical tissue indicating that it was a leukaemic phenomenon. This is the first case of an intronic point mutation to be reported in CLL. This mutation led to chaotic p53 expression and, interestingly, occurred in a case showing telomeric associations, a rare phenomenon in B-CLL.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
4/56. Intratumor heterogeneity of centromere numerical abnormality in multiple primary gastric cancers: application of fluorescence in situ hybridization with intermittent microwave irradiation on paraffin-embedded tissue.Our recent success in retrieving distinct fluorescence signals in response to centromere specific probing of paraffin-embedded tissues after intermittent microwave (MW) treatment provided the opportunity to analyze chromosome numbers or centromere abnormality in situ in human tumors in various clinicopathological settings. In this study, centromere numerical abnormality (CNA) was investigated by fluorescence in situ hybridization (FISH) in a case of multiple gastric cancer having intratumor histological heterogeneity. The different profiles as determined using a total of 20 specific probes on 4 multifocal lesions in the stomach confirmed the multi-clonality of these tumors. FISH with probes specific for chromosomes 10, 11, 16 and 18 revealed intratumor heterogeneity of the CNA, which corresponded to the histological heterogeneity. Our report clearly demonstrates, for the first time, intratumor heterogeneity of CNA and its association with the histological picture, and substantiates the applicability of the MW-assisted FISH protocol to paraffin-embedded pathological specimens.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/56. Synchronous oral leiomyosarcoma and squamous cell carcinoma.An unusual case of synchronous squamous cell carcinoma and leiomyosarcoma of the oral cavity is reported in a patient without any identified environmental risk or predisposing factors. The invasive squamous cell carcinoma involved the tongue, whereas the leiomyosarcoma was located in the soft palate. No immunostaining was found for human papillomavirus or Epstein-Barr virus, and in situ hybridization showed negativity for human papillomavirus dna within the tumor cells. Alterations of bcl -2, c-erb -b2 and Rb oncoproteins were not found immunohistochemically. Overexpression of p53 was detected by immunohistochemistry in both tumors, but p53 gene mutations were not found by polymerase chain reaction. Neither loss of heterozygosity of p53 nor microsatellite instability was detected in this patient. The smooth muscle nature of the leiomyosarcoma was confirmed by immunohistochemical methods. To our knowledge, synchronous smooth muscle and epithelial oral tumors have not previously been reported.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
6/56. Human papillomavirus type 16 dna in oral white sponge nevus.White sponge nevus (WSN) is a benign hereditary lesion of the mucous membranes. dna extracted from a biopsy specimen of oral WSN was assayed for the presence of dna sequences homologous to human papillomavirus (HPV) types 1, 2, 4, 6, 11, 13, 16, and 18 by Southern blot hybridization. Only HPV-16 homologous dna sequences were detected at a copy number of approximately 200 to 250 genome copies per diploid cell. The viral dna sequences did not appear to be integrated into the host cell chromosome. The finding of HPV-16 in an inherited lesion such as WSN indicates that caution must be exercised in ascribing a causal association in relation to the demonstration of HPV in other mucosal disorders.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
7/56. Intratubular germ cell neoplasia in infantile yolk sac tumor. Verification by tandem repeat sequence in situ hybridization.The strong association of intratubular germ cell neoplasia (ITGCN) with adult germ cell testicular tumors is well known, but studies noting the absence of ITGCN in certain germ cell neoplasms such as spermatocytic seminoma, childhood teratoma, and infantile yolk sac tumor (YST) have raised the issue of whether these latter neoplasms follow a different path of tumorigenesis, accounting for their more benign behavior. A case study illustrating the association of ITGCN with infantile YST is presented to challenge this hypothesis. In addition to the usual characteristic features that included strong cytoplasmic glycogen deposits, and focal placental alkaline phosphatase immunoreactivity, the atypical intratubular germ cells manifested triploidy by in situ hybridization using as probe a telomeric tandem repeat sequence, p1-79, specific to chromosome 1. The invasive YST cells, in contrast, showed evidence of tetraploidy by both in situ hybridization and flow and image cytometric studies, excluding the possibility that the atypical intratubular germ cells represented intratubular invasion by adjacent YST. These findings challenge the belief that the infantile YST follows a different path of tumorigenesis than its adult germ cell counterpart and suggest other hypotheses that might better explain its more benign behavior.- - - - - - - - - - ranking = 1.2keywords = hybridization (Clic here for more details about this article) |
8/56. Triple cancers in the urogenital area of a patient with aplastic anemia.Three epithelial neoplastic lesions, perineal Bowenoid papulosis, uterine cervical carcinoma, and bladder transitional cell carcinoma, which occurred in a mildly immunosuppressed patient who had aplastic anemia were studied for human papillomavirus (HPV) infection. In the Bowenoid papulosis, HPV type 16 dna was identified by polymerase chain reaction (PCR) and by in situ hybridization (ISH). In contrast, in the uterine cervical carcinoma, HPV 16 was not detected, although possibly another unidentified type of HPV in the lesion was suggested by the ISH findings. In the bladder transitional cell carcinoma, neither papillomavirus genus-specific (PGS) antigen nor HPV dna was found.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
9/56. Malignant lymphoma of the stomach in association with inflammatory myofibroblastic tumor of the spleen. A case report.We report on a case of a 40-year-old male patient who underwent a gastrectomy because of a biopsy-proven large B-cell lymphoma of the stomach. On surgery, a nodule in the spleen also was noted. Grossly and microscopically, the two lesions were different: the tumor of the stomach appeared white-gray on the cut surface and was a centroblastic variant of diffuse large B-cell lymphoma. Histologically, one perigastric lymph node was involved. Grossly, the splenic nodule was gray-yellow and had a histological appearance of an inflammatory myofibroblastic tumor (IMT). The association between malignant tumor and IMT is rare. In such an association, the latter lesion most often has been reported in the spleen. As EBV may be involved in the genesis of both lymphoma and IMT, we tested both lesions for its presence using in situ hybridization, but the tests were negative. It remains to be verified whether the association between lymphoma and IMT is more than fortuitous.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
10/56. composite lymphoma: angiocentric T-cell lymphoma (CD8 cytotoxic/suppressor T-cell) and diffuse large B-cell lymphoma associated with EBV, and presenting clinically as a midfacial necrotizing lesion.A composite lymphoma is defined as the simultaneous occurrence of two histologically different types of lymphomas situated in one anatomical location. Reports of composite B- and T-cell lymphomas, especially in the head and neck region, are rare. We describe a 76-year-old Taiwanese aboriginal female patient clinically presenting with a midfacial necrotizing lesion (MNL). Microscopic examination of the incisional biopsy specimen revealed extensive surface necrosis with infiltrates of inflammatory cells. Beneath the necrotic surface, there appeared to be two distinct populations of pleomorphic lymphoid cells exhibiting the characteristic features of the angiocentric distribution of the tumor cells and evidence of angiodestruction. Immunohistochemical staining revealed that these atypical lymphoid cells were positive for LCA, CD45, CD5, CD20, CD3 epsilon, CD8, bcl-2 and bcl-6 and negative for CD56, CD4, CD68, keratin, S-100, kappa and lambda. Furthermore, these atypical lymphoid cells also expressed EBV-encoded nuclear RNAs (EBERs) following in situ hybridization. Therefore, this was a case of composite lymphoma: angiocentric T-cell lymphoma (ATCL) (CD8 cytotoxic/suppressor T-cell) and diffuse large B-cell lymphoma (DLBL) associated with the Epstein-Barr virus (EBV) and presenting clinically as MNL.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
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