Are cellular polarisation and mitotic frequency prognostic factors for local recurrence in patients with ductal carcinoma in situ of the breast?

There is still no generally accepted histopathological classification system for ductal carcinoma in situ (DCIS) of the breast. Nuclear grade, with or without other histopathological parameters (i.e. comedo-type necrosis and cellular polarisation), has been demonstrated to yield prognostic information. A detailed method for the evaluation of the mitotic frequency in DCIS, based on an approach by Contesso, was used in this study. We also investigated if cellular polarisation and mitotic frequency were important for the ipsilateral local recurrence-free interval (IL-RFI) in 121 DCIS patients who had been operated upon with breast-conserving treatment (BCT) without radiotherapy. Both cellular polarisation and the mitotic frequency were associated with histopathological and cellular biological factors (in previous evaluations), and were of borderline significance for IL-RFI in the univariate analyses. However, when nuclear grade was included in the multivariate analyses (with or without the growth pattern), neither cellular polarisation nor the mitotic frequency were of any independent prognostic value.