The measurements were conducted in the operating rooms of the hospital where the tissues were excised. Once the tissue was excised from the patient, the pathologist assisted the one of the engineers (already at the hospital) responsible to conduct the measurement. The specimen were designed to permit at least one measurement of malignant tissue and at least one measurement of normal tissue. Occasionally, the measurement of normal tissue was not possible if, for example, the normal tissue occupied a volume of small proportion for every excised specimen. The specimens for dielectric properties measurement were classified as normal or malignant by the pathologist based on his own expertise and decision criteria (visual inspection, anatomy) and the per-operative histological examination. The measurements were directly performed on the bulk specimen. The patient age, tissue temperature at the time of measurement and time between excision and measurement for each sample were recorded.