The more people learn about how cancer cells do (or don't) metastasize, the more complicated the picture becomes... and it becomes more intriguing. https://knowablemagazine.org/content/article/health-disease/2025/how-cancer-cells-metastasize
@MarcAbrahams I remember hearing in an interview with a cancer researcher that while research on individual cancers is important, if you want to save lives, we should focus on metastasis. Nearly all cancer deaths result from metastasis. If you can control that, you can make nearly all cancers manageable and survivable.