In 2007, my then 31-year-old sister Cassandra had an aggressive form of breast cancer and had to have her breast removed. She went on to have preventative chemo and radiotherapy that continued for a year-and-a-half, but the cancer found a way to attach itself to other parts of her body. Four years later, she was diagnosed with incurable metastatic cancer - it was in her bones, liver and brain.
She had to be treated with an intensive course of chemotherapy. We were told she wouldn't survive, and if she did, her brain would be permanently affected.