Significance of DNA content and proliferative rate of the invasive carcinoma found in the mammographically directed breast biopsy.

During the last few years considerable effort has been made to find genetic and biochemical markers that could be used to predict the behavior of cancers with greater accuracy than that obtained by histologic grading or the assessment of other established morphologic features. Because there is considerable evidence that malignant neoplasms have cytogenetic abnormalities, and because atypical features of the nucleus such as pleomorphism and hyperchromasia are known to be prognostically unfavorable findings, quantitative analysis of nuclear DNA was a prime candidate for evaluation. Also, the rate at which malignant tumor cells replicate, and the fraction of tumor cells participating in the proliferative process, are of considerable interest to oncologists for use in assessing patient prognosis and for guiding decisions on the use of various endocrine and cytotoxic agents for adjuvant endocrine and chemotherapy.