No. 24: Nov-Dec 1982
"However, the most formidable obstacle to the successful treatment of disseminated cancer may well be the fact that the cells of a tumor are biologically heterogeneous. This phenotypic diversity, which allows selected variants to develop from the primary tumor, means not only that primary tumors and metastases can differ in their responses to treatment but also that individual metastases differ from one another. This diversity can be generated rapidly even when the tumors originate from a single transformed cell."
(Fidler, Isaiah J., and Hart, Ian R.; "Biological Diversity in Metastatic Neoplasma: Origins and Implications," Science, 217:998, 1982.)
Comment. The ability of single cancer cells to multiply into different kinds of cells, as well as propagate throughout an organism, seems to betoken an insidious biological entity, whose origin and purpose (?) we have hardly begun to comprehend. How could cancer have evolved if it leaves no progeny? How could natural selection leave us so susceptible to cancer?
Reference. The many enigmas of cancer are covered in categories BHH23-35 in our Catalog: Biological Anomalies: Humans II. For information on this book, visit: here.