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J Torhorst

Publications and source records attributed to J Torhorst.

158 records · Page 9Linked to original sources

MIB-1 (Ki-67) immunostaining of breast cancer cells in cytologic smears.

OBJECTIVE: The reliability of immunocytochemical evaluation of proliferation activity was tested using the monoclonal antibody MIB-1 on cytologic specimens. STUDY DESIGN: The study comprised 83 frozen tissue smears (FTSs) and 51 fine needle aspirates (FNAs) from 119 breast cancer patients. MIB-1 labeling indexes (LIs) were compared with various tumor parameters assessed on histologic material. RESULTS: MIB-1 LIs established on cytologic smears were significantly different in ductal and lobular carcinomas (P = .024) and correlated significantly with mitotic activity (P < .0001), histologic grade (P < .0001) and S-phase fraction (P < .0001). Essentially the same results were obtained on FTSs and FNAs. CONCLUSION: Proliferative activity can reliably be evaluated by FNA cytology, and the evaluation of MIB-1 LIs may complement cytologic grading of breast cancer. The evaluation of proliferation activity may, therefore, contribute to the selection of candidates for adjuvant chemotherapy.

Biopsy, Needle↗

Fluorescence in situ hybridization for detecting erbB-2 amplification in breast tumor fine needle aspiration biopsies.

OBJECTIVE: To evaluate the feasibility of erbB-2 amplification analysis of fine needle aspiration (FNA) biopsies. STUDY DESIGN: FNA smears and dissociated nuclei from 58 breast cancer samples were examined by dual-labeling fluorescence in situ hybridization (FISH) with probes for centromere 17 and the erbB-2 gene. The results were compared with the outcome of erbB-2 immunohistochemistry. RESULTS: Tumors were categorized according to the erbB-2/centromere 17 signal ratio. There were 23 tumors with high-level amplification, four cases with a low-level erbB-2 gain and 27 tumors with normal erbB-2 content. Four tumors showed an erbB-2 deletion, all in patients < or = 42 years of age. ErbB-2 amplification was strongly associated with positive erbB-2 immunostaining (P < .0001). Comparison of FISH analysis on dissociated cells and on FNA biopsies showed high correspondence (P < .0001). CONCLUSION: FISH allows reliable detection of erbB-2 gene amplification on FNA biopsies.

Adult↗

Analysis of proliferative activity using Ki-67 on cervical precancerous lesions and the relationship to p53 expression.

Neoplastic cell growth rate and the p53 expression have been recently analysed in invasive cervical carcinoma. Samples of 20 specimens with normal cervical epithelium and 73 specimens of dysplasia and carcinoma in situ (CIS) were immunostained with monoclonal antibodies to p53 and Ki-67 to examine the interrelationship between p53, Ki-67 and HPV status in cervical intraepithelial neoplasm. The presence of HPV was assessed by in situ DNA hybridization. Of dysplasias and CIS 79% were HPV positive. The growth rate of neoplastic cells was significantly correlated to the histological grade and the HPV status. The highest proliferation was found in poorly differentiated HPV 16/18 positive precancerous lesions. The analysis of the p53 expression showed no difference between various histological grades. However, the p53 oncoprotein was expressed significantly lower in HPV 16/18 positive neoplasms. The assessment of neoplastic cell growth rate offers a potentially valuable approach to predicting biological behaviour in intraepithelial neoplasms.

Biomarkers, Tumor↗

Taking a family history in cancer patients with a simple questionnaire.

A one-page family history questionnaire was validated in two European areas covered by population-based cancer registries. Information on malignant tumor occurrence in first degree relatives was collected from 193 cancer patients in Trieste, Italy and from 64 in Basel, Switzerland. They were then compared with the corresponding data stored in the registries' files. The sensitivity of the questionnaire was 85% (Trieste) and 74% (Basel), the specificity was 97% in both studies and the overall accuracy 95% (Trieste) and 94% (Basel). The questionnaire is recommended for use in different geographical areas covered by population based registries for comparative analyses of cancer related family histories.

Adolescent↗

Association of p27Kip1, cyclin E and c-myc expression with progression and prognosis in HPV-positive cervical neoplasms.

Recent studies demonstrated that a variety of human cancer cell lines express relatively high levels of p27Kip1 and that this might be associated with increased expression of Cyclin E. There is a feedback inhibitory loop between Cyclin E and p27Kip1, which can be counteracted by elevated c-myc activation. This study analyzed by immunohistochemistry the expression of p27Kip1, Cyclin E and c-myc in a series of HPV-positive cervical tissue samples representing various stages of cervical carcinogenesis, using 13 samples of normal epithelium, 24 low-grade CIN, 63 high-grade CIN, and 69 samples of invasive squamous cell carcinoma. To evaluate the cell proliferation, the Ki-67 Labelling Index (LI) was assessed. The presence of HPV was investigated by in situ DNA hybridization. We did not find any correlation between p27Kip1 expression and Ki-67 LI in normal and tumor tissue samples. There was evidence for an increase of p27Kip1 levels from low-grade to high-grade CIN. Cyclin E, c-myc and the Ki-67 LI were significantly increased during cervical carcinogenesis. Cyclin E and c-myc were positively correlated to cell proliferation in pre-cancerous lesions, but not related to overall survival in invasive carcinomas. Contrary to that, high levels of p27Kip1 are associated with poor overall survival in invasive cervical carcinomas of clinical stage IB. This may reflect the counteracting function of c-myc in blocking p27Kip1, thus representing the worst condition of a disturbed tumor cell cycle in cervical carcinoma, ultimately induced by HPV.

Cell Cycle Proteins↗