5 research outputs found
Proliferation and aneusomy predict survival of young patients with astrocytoma grade II
The clinical course of astrocytoma grade II (AII) is highly variable and not reflected by histological characteristics. As one of the best prognostic factors, higher age identifies rapid progressive A II. For patients over 35 years of age, an aggressive treatment is normally propagated. For patients under 35 years, there is no clear guidance for treatment choices, and therefore also the necessity of histopathological diagnosis is often questioned. We studied the additional prognostic value of the proliferation index and the detection of genetic aberrations for patients with A II. The tumour samples were obtained by stereotactic biopsy or tumour resection and divided into two age groups, that is 18–34 years (n=19) and 35 years (n=28). Factors tested included the proliferation (Ki-67) index, and numerical aberrations for chromosomes 1, 7, and 10, as detected by in situ hybridisation (ISH). The results show that age is a prognostic indicator when studied in the total patient group, with patients above 35 years showing a relatively poor prognosis. Increased proliferation index in the presence of aneusomy appears to identify a subgroup of patients with poor prognosis more accurately than predicted by proliferation index alone. We conclude that histologically classified cases of A II comprise a heterogeneous group of tumours with different biological and genetic constitution, which exhibit a highly variable clinical course. Immunostaining for Ki-67 in combination with the detection of aneusomy by ISH allows the identification of a subgroup of patients with rapidly progressive A II. This is an extra argument not to defer stereotactic biopsy in young patients with radiological suspicion of A II
Identification and Chromosomal Assignment of USP1, a Novel Gene Encoding a Human Ubiquitin-Specific Protease
ĂŤndice de astrĂłcitos gemistocĂticos e imuno-expressĂŁo da proteĂna p53 em astrocitomas, grau II e III OMS Fraction of gemistocytic astrocytes and immunoexpression of p53 protein in astrocytomas grade II and III (WHO)
Foram estudados, retrospectivamente, 22 pacientes com diagnĂłstico de astrocitomas grau II (n=17) e III (n=5), OMS, no perĂodo de 1990 a 1998, cujos laudos histopatolĂłgicos descreviam a presença gemistocitos com o objetivo de determinar o Ăndice de astrĂłcitos gemistocĂticos, investigar a imuno-expressĂŁo da proteĂna p53 e confrontá-los com o intervalo atĂ© a recorrĂŞncia da neoplasia. O Ăndice de astrĂłcitos gemistocĂticos, em cada caso, foi calculado a partir da razĂŁo entre o nĂşmero de gemistocitos e o nĂşmero total de cĂ©lulas neoplásicas contadas, no mĂnimo 1000. Imuno-expressĂŁo nuclear da proteĂna p53 foi avaliada em astrĂłcitos e gemistocitos neoplásicos; tanto a freqĂĽĂŞncia (7/22), como o Ăndice de imuno-expressĂŁo positiva da p53 em gemistocitos, independentemente do grau histolĂłgico da neoplasia, foram inferiores aos relatados na literatura. NĂŁo se observou correlação entre o Ăndice de astrĂłcitos gemistocĂticos e a imuno-expressĂŁo positiva da p53.<br>Twenty-two patients with astrocytomas, grade II or III WHO, were studied from 1990 to 1998. In all cases, histopathology showed that the astrocytomas had a gemistocytic component. The aims of this study were to establish the fraction of gemistocytic astrocytes, to investigate p53 protein immunoexpression and to evaluate correlations between these two parameters with the tumour outcome. Tumor cells were quantified at high-power magnification (x400). At least 1000 neoplastic cells (small neoplastic astrocytes plus gemistocytes) were counted in each specimen. The percentage of gemistocytes was defined as the gemistocytic index. Nuclear expression of p53 protein was evaluated in neoplastic astrocytes and gemistocytes. Both the frequency (7/22) as well the p53 immunoexpression indices in gemistocytes, regardless of the grade of the astrocytomas, were inferior from those reported in the literature. No correlation was found between the gemistocytic indices and the p53 immunoexpression