Biomedical subjects

Xiao Rong Sun

Publications and source records attributed to Xiao Rong Sun.

3 recordsLinked to original sources

PubMed2005

Detection of cervical cancer and high grade neoplastic lesions by a combination of liquid-based sampling preparation and DNA measurements using automated image cytometry.

OBJECTIVE: To establish if measurements of DNA ploidy could be used to assist cytopathologists and cytotechnologists in population based cervical cancer screening programs in countries where manually reading the slides is impossible due to the lack of sufficient skilled cytotechnologists. The goal of such program is to identify only clinically significant lesions, i.e. those where a clinical intervention to remove the lesion is required immediately. STUDY DESIGN: A total of 9905 women were enrolled in the study. Cervical samples were taken with a cervix brush that was then placed into a fixative solution. The cells were separated from mucus by mechanical and chemical treatment and then deposited onto microscope slides by a cytocentrifuge. Two slides were prepared from each case; one slide was stained by Papanicolaou stain for manual cytology examination, while the other slide was stained by a DNA specific stain. The latter slide was used to determine the relative amount of DNA in the cell nuclei. RESULTS: A total of 876 women were followed by colposcopy examination where biopsies were taken from the visible lesions or from suspicious areas and histopathology diagnosed 459 as normal or benign cases, 325 as CIN1, 36 as CIN2, 25 as CIN3/CIS, and 31 as invasive cancer. Of these 876 cases, manual cytology called 655 normal or ASCUS, 197 as LSIL, 16 cases as HSIL, and 8 as cancer. DNA measurements found 704 cases having no cells with DNA greater than 5c, 98 cases where there were 1 or 2 cells having DNA amount greater than 5c, and 74 cases where there were 3 or more cells having DNA amount greater than 5c. If manual cytology were to be used to refer all cases of HSIL and cancer to colposcopy and biopsy, 23 lesions that had to be removed would have been discovered (2 CIN2, 11 CIN3/CIS, and 10 cancers), for a sensitivity of 25.0+/-5.2% at specificity of 99.9+/-0.1%. If DNA assisted cytology were to be used instead, and all cases having 3 or more cells with DNA amount greater than 5c were to be referred to colposcopy and biopsy, then 50 lesions that had to be removed would have been discovered (10 CIN2, 15 CIN3/CIS and 25 cancers) for the sensitivity of 54.3+/-6.2% at specificity of 96.9+/-0.6%. CONCLUSIONS: The study suggests that screening for high grade cervical neoplastic lesions and cervical cancer by DNA assisted cytology could be implemented with minimal use of skilled cytotechnologists, at least in those countries where it would be difficult to introduce population based screening for cervical cancer due to the lack of availability of such skilled cytotechnologists.

Biopsy↗

PubMed2003

In vitro model for studying malignancy associated changes.

Malignancy associated changes (MAC) can be defined as subtle morphological and physiologic changes that are found in ostensibly normal cells of patients harboring malignant disease. It has been postulated that MAC have a potential to become a useful tool in detection, diagnosis and prognosis of malignant diseases. An in vitro cell culture model system was designed to study interactions between non-small cell lung cancer (NSCLC) and the normal bronchial epithelium of the human respiratory tract in vivo to see if the MAC-like phenomenon can be detected in such a system. In this study we examined changes in nuclear features of normal human bronchial epithelial cells (NHBE) when they were co-cultured with cells derived from a lung cancer cell line NCI-H460. Using discriminant function analysis, nuclear features were determined which allow maximal discrimination between normal cells incubated with or without cancerous cells. Our results demonstrate that MAC appear to be specific to changes induced by malignancy, and that these changes differ from those induced by growth factors in the serum. This study provides evidence in support to the hypothesis that MAC are induced by a soluble factor(s) released by malignant cells. Colour figure can be viewed on http://www.esacp.org/acp/2003/25-2/sun.htm

Bronchi↗

PubMed2002

Increase of sensitivity of sputum cytology using high-resolution image cytometry: field study results.

Lung cancer remains the leading cause of cancer deaths in the developed world. There is no widely accepted method to screen for this cancer. The most commonly used method remains conventional sputum cytology, but this method is hampered by low sensitivity. We tested the hypothesis that sensitivity of sputum cytology for early lung cancer can be greatly improved by using image analysis of sputum cells, at a modest reduction of specificity. The study was double-blinded and used sputum samples from subjects with well-characterized clinical diagnoses. There were 177 cancers, 98 dysplasias, and 558 normals. The study samples were separated into two independent sets: training set and test set. Sputum samples were collected prospectively from subjects with a high probability of having lung cancer. Seven institutions from five countries participated in the study. All subjects had complete clinical diagnoses which included, as a minimum, negative chest x-rays for all negative cancers, while all cancers had confirmed tissue pathology. Samples were prepared according to the Saccomanno method. For conventional cytology, slides were stained using Papanicolaou stain. For image analysis, slides were stained using a DNA-specific (Feulgen-Thionin) stain. An automated, high-resolution image cytometer was used for measurements. At 90% specificity, sensitivity of 60% can be achieved for adenocarcinoma, compared to only 14% sensitivity of conventional cytology (at 99% specificity). Similarly, 45% sensitivity at 90% specificity can be reached for stages 0 and I lung cancer, compared to only 14% (at 99% specificity) using conventional cytology.Cytometry combined with conventional cytology shows an increase in sensitivity to early-stage cancer and to adenocarcinomas compared to conventional cytology alone. While the results are encouraging, the sensitivity to detect early lung cancer should be further improved to 70-80% at 90-95% specificity before this test can be considered for screening of high-risk individuals for lung cancer. Cytometry (Clin. Cytometry) 50:168-176, 2002.

Double-Blind Method↗