In the present work, we investigated the dielectric characterization of cylindrical shaped tissues via an open-ended coaxial probe. So long as biological tissues are not stiff, in this contribution we look for the minimum cylinder diameter and the related insertion depth in the tissue detectable by our probe. From numerical simulations, we derived the reflection coefficient probe aperture plane, and then we used it as input data in our Virtual Transmission Line Model (VTLM) based algorithm for dielectric properties reconstruction. Furthermore, we numerically analyzed the presence of a dielectric coating which hosts the tissue under test and wraps the coaxial probe itself. The aim is exploiting the sample shape derived from a core needle biopsy procedure which allows avoiding sample manipulation. The same dielectric coating allows reducing fringing field effect at the probe-to-tissue region thus enhancing probe dielectric reconstruction properties. The proposed system can be used in medical field as a decisional support in pre-pathological malignant tissue recognition purposes.