The clinical value of flow cytometric DNA content analysis in patients with soft tissue sarcomas

Nuclear DNA-Content in Mesenchymal Lesions in Dogs: Its Value as Marker of Malignancy and Extent of Genomic Instability

DNA-aneuploidy may reflect the malignant nature of mesenchymal proliferations and herald gross genomic instability as a mechanistic factor in tumor genesis. DNA-ploidy and -index were determined by flow cytometry in canine inflammatory or neoplastic mesenchymal tissues and related to clinico-pathological features, biological behavior and p53 gene mutational status. Half of all sarcomas were aneuploid. Benign mesenchymal neoplasms were rarely aneuploid and inflammatory lesions not at all. The aneuploidy rate was comparable to that reported for human sarcomas with significant variation amongst subtypes. DNA-ploidy status in canines lacked a relation with histological grade of malignancy, in contrast to human sarcomas. While aneuploidy was related to the development of metastases in soft tissue sarcomas it was not in osteosarcomas. No relation amongst sarcomas was found between ploidy status and presence of P53 gene mutations. Heterogeneity of the DNA index between primary and metastatic sarcoma sites was present in half of the cases examined. Hypoploidy is more common in canine sarcomas and hyperploid cases have less deviation of the DNA index than human sarcomas. The variation in the presence and extent of aneuploidy amongst sarcoma subtypes indicates variation in genomic instability. This study strengthens the concept of interspecies variation in the evolution of gross chromosomal aberrations during cancer development.

Expression of P53 Protein and Dna Flow Cytometry in Gastric Adenocarcinoma: Implications in Patients Treated with Adjuvant Etoposide, Adriamycin and Cisplatin

Aims and background

We evaluated the prognostic value of p53 protein, DNA content and S-phase fraction in patients with adenocarcinoma of the stomach or the gastroesophageal junction treated with adjuvant etoposide, doxorubicin and cisplatin.

Methods and study design

Thirty-five consecutive patients with stage II or III gastric or gastroesophagial junction adenocarcinoma treated with at least two cycles of adjuvant etoposide, doxorubicin and cisplatin after curative gastric resection were included. The expression of p53 protein was determined by immunohistochemistry and DNA content by flow cytometry. The presence of p53 expression and DNA content was compared with clinicopathological features.

Results

Median age was 54 years (range, 31–71). P53 expression was detected in 42.9% (15 of 35) of gastric cancer tissues of the patients. Aneuploidy was observed in 31.4% of patients, and S-phase fraction was more than 10% in 22.9%. P53 immunoreactivity (33.3% vs 47.8%) was more common in advanced disease. There was no association among p53 immunoreactivity, DNA content and S-phase fraction. We also found no significant relationship between p53 immunoreactivity, DNA content, S-phase fraction or other clinicopathological parameters. In univariate analysis, the involvement of lymph nodes was a significant predictor of a poor outcome (P = 0.001). Also, p53-positive patients had a poor survival close to the level of significance (P = 0.051). Likewise, p53 immunoreactivity (P = 0.0071), in addition to lymph node involvement (P = 0.0016), were the independent prognostic factors in multivariate analysis.

Conclusions

This trial supports the results of previous reports that p53 immunoreactivity is a prognostic factor for patients with adenocarcinoma of stomach or gastroesophageal junction treated with adjuvant chemotherapy.