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Diagnostic confirmation of cancer in solid organs is based on biopsy findings. In a standard 12-core prostate biopsy protocol, conventional biopsy needles sample only 0.95% (~0.228 cm3) of a typical 24-cm3 prostate gland. The primary objective of this study was to enhance the sensitivity of standard biopsy protocol by gauging electrical properties of tissue simultaneously with tissue extraction for histopathology analysis. A conventional biopsy (Bx) needle was instrumented with an electrical impedance spectroscopy (EIS) sensor to interrogate the tissue volume surrounding the needle tip. The EIS-Bx device was evaluated in a series of saline bath and ex vivo porcine experiments. It was found to sense a volume of 0.286 cm3 of tissue around the needle tip. EIS measurements were recorded from three ex vivo human prostates using the device, and the extracted biopsy cores were histologically assessed. Prostate conductivity σ ranged from 0.179 to 0.3310S/m for benign tissues and 0.0746 to 0.0837 S/m for malignant tissues at frequencies ranging from 1 to 100 kHz. Relative permittivity εr ranged from 2.10 × 106 to 2.9 × 104 for benign and 6.63 × 105 to 5.3 × 103 for cancer tissues over the same frequency range. Both are found to be significantly higher in normal prostate tissues than in malignant tissue (p <; 0.00001).