Identification of a low‐risk group of stage I breast cancer patients by cytometrically assessed DNA and nuclear texture parameters

Image cytometrical measurements were performed on Feulgen‐stained cells from 329 stage I breast cancers (pT1pN0,M0,R0). For each patient, several DNA (ploidy, S‐phase fraction, exceeding rates, 2c deviation index, ploidy balance, entropy, and histogram typing), morphometric (area and radius of nuclei), and textural parameters (mainly co‐occurrence and run‐length) were calculated. The prognostic value of these parameters was investigated by multivariate Cox regression analysis, considering a distant recurrence‐free survival of 8 years as the prognostic criterion. In the multivariate analysis, one DNA parameter (histogram type) and two textural parameters (co‐occurrence and variation of the average heterochromatin area) were proven to have independent prognostic value. Using a linear combination of these variables, a prognostic factor was calculated for each individual patient. Patients were stratified using this factor into several groups according to their risk for distant recurrence. Thus, a low‐risk group of stage I patients was identified, remaining distant recurrence‐free for 8 years. In addition, a group of patients with a worse prognosis and an 8‐year recurrence rate of about 26 per cent was identified, compared with the average distant recurrence rate of all stage I patients of 13 per cent. A combination of DNA and textural parameters can provide powerful prognostic information in stage I breast carcinomas and may allow a better selection of patients for different therapy protocols.