Flow Cytometric Analysis to Assess the Malignant Potential of Phyllodes Tumor

To evaluate DNA content as a prognostic indicator in phyllodes tumor of the breast, flow cytometric DNA analyses were performed retrospectively in 13 patients who were selected, based on the availability of paraffin-embedded tumor specimens. ALL were women with an average age of 41.9 years and a mean follow-up of 51.2 months. Pathologically, 3 patients (23.0%) had malignant tumor and 10(77.7%) had benign lesions. The patients with malignant tumors tended to be older and had larger tumors. Aneuploidy was seen in one patient with malignant tumor (7.7%), with the S-phase fraction ranging from 0.8 to 12.6. This patient died of lung metastases 6 months after mastectomy. One benign tumor showing diploid, developed local recurrence 100 months after lumpectomy. DNA stem cell lines were not detected in the only patient with aneuploid tumor. There was no significant correlation between DNA content and local recurrence. In this series, the number of patients was too small to draw the certain conclusions from date. However, it appears that, compared to diploid tumors, aneuploid tumor are more often malignant and have poorer prognosis. Our study indicates that DNA content has little prognostic value, DNA aneuploidy appears to be associated with a poor prognosis.