Biofunctional characteristics of in situ and invasive breast carcinoma.

Purpose: The increasing use of breast-conserving surgery makes it essential to identify biofunctional profiles responsible for the progression of in situ to invasive carcinomas to facilitate the detection of lesions that are most likely to relapse or progress and, thus, to be able to offer patients tailored treatment options. Our objective was to analyse and compare biofunctional profiles in ductal carcinomas in situ (DCIS) and invasive ductal carcinomas (IDC). We also aimed to identify markers in tumor and normal surrounding tissues that may be predictive of locoregional recurrence in patients with DCIS.
Methods: Biofunctional parameters including mitotic activity, estrogen receptor, progesterone receptor, microvessel density (MVD), c-kit and p27 expression were evaluated in 829 in situ and invasive carcinomas. The impact of the biomarker profiles of DCIS, IDC and normal surrounding tissues on loco-regional recurrence was analyzed.
Results: A progressive increase in cell proliferation and a concomitant decrease in steroid hormone receptor-positive lesions was observed during the transition from in situ to invasive carcinomas, as also within each subgroup as grade increased. Conversely, p27 expression and MVD dramatically decreased during the transition from in situ to invasive carcinomas. Finally, we found that a low c-kit expression was indicative of IDC relapse.
Conclusions: Cell proliferation, hormonal and differentiation characteristics differed in DCIS with respect to IDC, and the main variation in the transition between the two histologic lesions was the decrease in p27 expression and MVD.