摘要:

HMGI(Y) and HMGI-C are members of a distinct family of “high mobility group” (HMG) proteins that are nonhistone chromatin-associated proteins initially characterized by high electrophoretic mobility in polyacrylamide gels (hence the acronym HMG). Recent studies have shown that HMGI(Y) and HMGI-C are important elements with a role in the regulation of chromatin structure and function. Like other HMG proteins they are responsible for the correct three-dimensional configuration of protein-DNA complexes and therefore play a key role in important cellular processes such as DNA transcription. Aberrant HMGI(Y) and HMGI-C expression generally correlates with a malignant tumor phenotype. However, HMGI(Y) and HMGI-C dys-regulation, as a result of specific chromosomal rearrangements, is also being identified in a variety of common benign mesenchymal tumors such as lipomas and uterine leiomyomas making HMGI(Y) and HMGI-C genes probably the most commonly rearranged genes in human neoplasms. While a precise definition of the HMGI(Y) and HMGI-C role in tumor initiation and progression is still missing, it is likely that future investigations will contribute valuable insights to the understanding of human neoplasia.

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Before the designationsborderline malignancyandlow malignant potentialwere used, the surface epithelial-stromal tumors of the ovary were simply classified into benign and malignant categories. The introduction of the borderline category of tumors has been a great advancement in classification, because it has set apart from the general group of surface epithelial cancers a subgroup with a much better prognosis, stage-for-stage, than that of conventional ovarian carcinomas. Over the last 20 years, pathologists have learned to recognize the distinctive clinicopathologic features of serous borderline tumors as well as the adverse prognostic significance of the associated invasive peritoneal lesions, whether they may represent true implants or independent primary tumors. We have urged our surgical colleagues to search for the peritoneal lesions, and sample them meticulously, and advised our fellow oncologists not to administer adjuvant therapy to patients withnoninvasive implantslacking malignant epithelial cells. There is now convincing evidence in the literature that the only fatal cases of serous borderline tumors are those associated withinvasive implants, and chemotherapy is indicated only for these rare tumors. It has also been demonstrated that StageIintestinal mucinous borderline tumors and noninvasive well-differentiated mucinous carcinomas both have an almost equally good prognosis. The current treatment for pseudomyxoma peritonei is still unsatisfactory, but we have recently learned that most of the mucinous ovarian tumors associated with pseudomyxoma peritonei are secondary to similar tumors of the appendix. In the remaining cases, however, the ovarian tumor appears to be responsible for the pseudomyxoma peritonei. Borderline tumors also exist in the endometrioid, clear cell, and Brenner surface epithelial categories, but these tumors have been too rare for clear delineation of their clinical and pathologic features. Recently, some investigators have proposed to abandon the borderline category and to return to the old benign-malignant classification system by dividing unevenly the borderline tumors into a larger group ofatypical proliferativeepithelial cystadenomas and a smaller category of recently described but still not well-characterized noninvasive carcinomas. In the author's opinion, such a recommendation is misleading because it ignores the possibility of rare but significant behavioral exceptions on each of these two groups of tumors. Furthermore, careful tumor staging is mandatory in both instances regardless of the type of terminology used. It is hoped that by keeping the borderline designation, knowledge on this group of ovarian tumors will continue to expand as it has been until now.

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

On: Collagenous fibroma (desmoplastic fibroblastoma): A clinicopathologic analysis of 63 cases of a distinctive soft tissue lesion with stellate-shaped fibroblasts. Miettinen M, Fetsch JF.Hum Pathol1998;29:676–82Collagenous fibroma is a distinct, benign, fibroblastic/myofibroblastic proliferation, probably neoplasm. It is a slow-growing tumor arising in predominantly subcutaneous tissue. This tumor is composed of stellate-shaped fibroblasts and abundant interstitial collagen. Since none of reported collagenous fibromas recurred, simple excision is an appropriate treatment. Collagenous fibroma should be differentiated from fibromatosis, which has a high risk of local recurrence if simple local excision is done. Fibromatosis is more cellular and shows short fascicular arrangements of tumor cells and greater infiltration at the periphery than collagenous fibroma.

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

On: Clinicopathological significance of poorly differentiated thyroid carcinoma. Nishida T, Katayama S, Tsujimoto M, Nakamura J, and Matsuda H,Amer J Surg Pathol1999;23:205–11Descriptions of poorly differentiated thyroid carcinomas, tumors with outcomes midway between that associated with well-differentiated and anaplastic carcinomas, have been prominent in the literature of the recent past. The neoplasms are characterized by the finding of poorly differentiated areas within papillary and follicular carcinomas. The work of Sakamoto clearly separates a group of poorly differentiated carcinomas, based on outcomes, from well-differentiated and anaplastic forms by the identification of schirrous, solid, and trabecular areas within papillary and follicular carcinomas. However, the presence of similar areas within more “benign” forms of papillary and follicular carcinomas may obviate the easy identification of such neoplasms in daily practice. This article presents a refinement of Sakamoto's classification and although suffering from the same limitations, may be of some practical value.

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

On: Sialoblastoma: Clinicopathological/immunohistochemical study. Brandwein M, Said Al-Naeif N, Manwani D, Som P, Goldfeder L, Rothschild M, Granowetter L.Am J Surg Pathol1999;23:342–8This commentary addresses the histologic spectrum of salivary gland neoplasms in children with emphasis on perinatal tumors. Histopathologically, perinatal tumors fall into four categories: 1) histologically benign with adult counterpart, 2) hamartomas, 3) embryomas-sialoblastomas, and 4) histologically and biologically malignant adult analogue tumors. Although the criteria to serrate benign from malignant sialoblastomas are not well-established, the following histologic features would favor an aggressive clinical course: perineural and/or vascular spaces invasion, necrosis, and a cytologic atypia beyond the expected for embryonic epithelium.

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1072-4109    

出版商:OVID    

年代:1999

数据来源: OVID