Biomechanical modeling of tumor classification and growth

Abstract

Palpation is an important clinical diagnostic practice which is based on the fact that tumors tend to be stiffer than the surrounding normal tissue. None of the modern, non-invasive, imaging modalities (such as CT scan, Magnetic Resonance Imaging, or Ultrasound) used today by radiologists to find and diagnose tumors provides the critical information about the stiffness of the imaged tissues. The clinical observation of palpation can be explained theoretically by the following hypothesis: the Young’s modulus of tissues helps differentiating not only between normal and abnormal tissues but, most importantly, between benign (not cancerous) and malignant (cancerous) tumors. In this paper we study tumor classification and growth with the help of biomechanical modeling. First, we propose a novel mechanical model of differentiating between benign and malignant tumors based on their corresponding Young’s moduli obtained using information about tissue microstructure provided by image mass spectroscopy. The second model shows how the mechanical properties of tumors affect their growth. By replacing the first order temporal derivative in this mechano-growth model with a fractional order derivative we are able to predict when a benign tumor turns into cancer.