The physics of cancer recurrence and metastasis*

We frame cancer progression as state changes of small-n cancer cell communities that are relevant for evolutionary and physical processes during cancer recurrence and metastasis: poly-aneuploidy, heterogeneity, speciation, resistance, evasion, and intravasation or invasion. We propose the following state changes leading to metastatic cancer, somewhat speculatively in the order in which the states flow towards full-blown inoperable and highly resistant metastatic cancer.

1) Metapopulation (small population) dynamics

2) Aneuploid-Polyploid Transition.

3) Speciation.

4) Resistance.

5) Evasion.

6)  Invasion.

Although we certainly cannot cover all the state changes from a quantitative physics perspective in 10 minutes (!), we will attempt to present the mathematical and physical foundations of these states with relevant equations.

We discuss a physics perspective, why it is that metastatic cancer remains such an unsolved problem. We try to emphasize that the field of physics has much to offer the cancer biologists and oncologists in methodology to crack the nut of lethal cancer metastasis.  We would like to think that this brief screed could serve as a call to arms for the physics community.  But this call to arms for physicists cannot mean they should simply apply what they already know to metastatic cancer, they must realize that metastatic cancer may actually provide new physics insights not contained in the conventional physics canon.  In the words of Stanislaw Ulam as said to the late Hans Frauenfelder, "ask not what physics can do for biology, ask what biology can do for physics"