That seems rather grim that killing part of a tumor accelerated its outward growth. I wonder if cancers are considered on the continuum of life like viruses? Our bodies are a bunch of individual cells that have been yoked together in a very complex way. Cancer seems to sometimes be an internal misguided revolution or throwback maybe.
There is a transmissible dog tumor which originated with handwave wolves. Apparently there are possibly others. (TIL!)
It's more akin to infinite loop since cells divide without appropriate boundaries. In cell division there's defined stages, normal cells should go into resting stage G0 https://en.wikipedia.org/wiki/G0_phase if they don't you have a tumour and when more checks and balances go awry that might lead to cancer