She wrote on social media site Tumblr at the time: “I’m writing to you with an update I wish I wasn’t giving you, but it’s important and I’m used to sharing important events in my life with you.
“Usually when things happen to me, I process them and then write music about how I feel, and you hear it much later. This is something my family and I thought you should about now.”
The 35-year-old singer continued: “I’d like to keep details of her condition and treatment plans private, but she wanted you to know. She wanted you to know why she may not be at as many shows this tour. She’s got an important battle to fight.”
Swift also wrote a deeply personal essay when her mother’s cancer returned in 2019 – which later led to the discovery of brain tumour during her treatment.
She wrote in Elle magazine: “It taught me that there are real problems and then there’s everything else. My mom’s cancer is a real problem. I used to be so anxious about daily ups and downs.
“I give all of my worry, stress and prayers to real problems now.”
She then shared that her father had been diagnosed with the disease previously, although did not give any further details.
She wrote: “Both of my parents have had cancer.”
