Neoplasia - 3

1. Biology of Tumor Growth

   1. Normal growth - polyclonal growth well regulated

   2. Hyperplasia - excessive polyclonal growth regulated response to cell signals

   3. Benign tumors - clonal proliferation limited response to cell signals

   4. Malignant tumors - immortalized clone loss of cell regulation

With that said, there is no generally accepted, unified concept of the biological mechanisms that underlie the development of neoplastic disease.

5. The panel illustrates clonal evolution of tumors and generation of tumor cells heterogeneity. New subclones arise from the descendants of the original transformed cell, and with progressive growth the tumor mass becomes enriched for those variants that are more adept at evading host defenses and are likely to be more aggressive.

Category: Pathology Notes