Sophie Kinsella, the author behind the “Shopaholic” book series, shared on Wednesday that she has been undergoing treatment for an “aggressive” form of brain cancer.

Kinsella, 54, whose real name is Madeleine Sophie Wickham, wrote on Instagram that she was diagnosed with glioblastoma at the end of 2022. She said she waited to share her health battle because she wanted to make sure her children could “process the news in privacy and adapt to our ‘new normal.'”

“I have been under the care of the excellent team at University College Hospital in London and have had successful surgery and subsequent radiotherapy and chemotherapy, which is still ongoing,” she wrote Wednesday.

“At the moment all is stable and I am feeling generally very well, though I get very tired and my memory is even worse than it was before!”

The comments section of Kinsella’s post was quickly filled with love and support.

“Sending you love, best wishes and prayers,” one person wrote.

“This news hurts me on a personal level. I have a really special place in my heart for you, the impact you have had on me is larger than life. Sending lots of love and healing vibes your way,” another commented.

“Sending all my love from Brazil! You’re very important in my development as a reader and writer, and I’m so grateful to you. Wish all the best,” one reader posted.

Publishing company Penguin Books wrote: “Sending so much love and strength Sophie.”

Glioblastoma is the most common type of malignant brain tumor among adults, according to WebMD. Symptoms depend on where the tumor is located on the brain but can include seizures, constant headaches, trouble speaking, memory loss and vomiting.

Treatment includes surgery, radiation, chemotherapy or different forms of therapy such as electric field therapy, which uses electrical fields to target cells in the tumor while not hurting normal cells, according to WedMB.

Kinsella ended her post by thanking her family, friends and readers for their support and offering some encouragement to people battling cancer.

“To everyone who is suffering from cancer in any form I send love and best wishes, as well as to those who support them. It can feel very lonely and scary to have a tough diagnosis, and the support and care of those around you means more than words can say,” she posted. “I’ll be in touch soon, and in the meanwhile, greetings from sunny London.”

Kinsella is best known for her “Shopaholic” book series, which inspired the 2009 movie “Confessions of a Shopaholic” starring Isla Fisher as the character Rebecca Bloomwood.

Her latest book, “The Burnout,” was released in October 2023.