This theoretical investigation proposes the preliminary stage detection of cancer cells using a prism-based surface plasmon resonance biosensor. The surface plasmon resonance (SPR) biosensor is label-free and rapid; it supports real-time investigations, including greater sensitivity, and it has an enormous possibility for detecting different forms of cancer. The refractive index alteration of cancer cells is 1.360-1.401. The performance of the SPR sensor has been analyzed. The different types of cancer cells for skin, cervical, blood, adrenal, and breast (type I and II) have been analyzed, and sensitivities of 292, 384, 229, 242, 254, and 261 (degree/RIU) have been achieved, respectively. A high figure of merit of 115.2RIU-1 has been achieved for HeLa cells and achieved detection accuracy of 0.32deg-1 for basal cells.