Sydney Towle, who documented her treatment for a form of bile duct cancer called cholangiocarcinoma on social media, has died.The 26-year-old’s family announced Aug. 6 on her Instagram that she passed away the day before. A graphic reads, “An endless ray of sunshine. A daughter, sister, and friend to so many.” The caption then reads, “We will always love you so much Sydney. I am so proud of how hard you fought. I love you.”On TikTok, Towle’s family shared a message with her supporters: “She fought really hard, and we’re so proud of her,” said Austin Towle, her brother. “And we thank all of you for your support over the years.”Her mother added, “We love you and thank you for all of your kind messages of support and love. We really appreciate it and she will not be forgotten.”News of Towle’s death comes three years after her cancer diagnosis.In 2023, then-23-year-old Towle noticed a lump and a burning sensation in her abdomen. What she and doctors thought was a hernia was later discovered to be cholangiocarcinoma, a rare cancer that forms in the group of tubes, called ducts, that connect the liver, gallbladder and small intestine, according to the National Cancer Institute.Five months of chemotherapy and immunotherapy reduced the size of the mass, then most of what remained of the tumor was removed in surgery, Towle told TODAY.com in a November 2024 interview. Some of the cancer the surgeons couldn’t remove still lined her liver, so doctors said they’d monitor it for growth with regular scans.An MRI a few months later revealed a lesion. A month later it had doubled in size.“I don’t think I’ve processed it,” Towle told TODAY.com. “I’ve kind of disassociated from it.”Following her move to New York City, Towle teamed up with new doctors to develop a new treatment plan.On TikTok, she regularly shared updates about her treatment and wellbeing with followers.“I’m bringing light to this, and so that has encouraged me to continue posting and sharing, especially when I am not doing well or when I receive good news,” she told TODAY.com. “It always seems to help people feel less alone, like, they’re not the only ones that are going through something that’s very challenging.”Following the subsequent rounds of treatment, Towle updated her followers in a TikTok post on May 17, 2026, explaining the cancer had spread to her peritoneum, the membrane that lines the abdomen and pelvis. Two days later, she revealed her oncologist’s decision to no longer treat her and instead transition her to end-of-life care.“I said, ‘No.’ So, we are switching hospitals,” Towle said in the video. “We’re not at the point where we’re giving up.”On June 8, Towle documented a day at the hospital during which she learned she had developed lung tumors.On June 29, she posted about having had surgery and said, “I think we’re on the come-up.” On July 12, she’d posted about chemotherapy and immunotherapy treatments she’d received. And by July 21, she noted she’d been hospitalized for about a month and was now waiting to see if her treatments were working.Towle’s account went quiet shortly after that.On Aug. 4, her brother, Austin Towle, posted a photo on TikTok of loved ones standing next to a hospital bed. “Sydney has been moved to hospice and is surrounded by her friends and family. Thank you all for your love and support❤️,” he wrote.She died a day later on Aug. 5.“People always ask why I’m so positive,” Towle said in a June 2026 TikTok post. “Why would I not envision the best-case scenario, the best way of things working out?”“Nobody knows for sure what’s going to happen; like, miracles happen every day.”What Is Cholangiocarcinoma?Cholangiocarcinoma is also known as bile duct cancer, as it forms in the tubes throughout the body that carry a type of digestive fluid called bile. The bile ducts connect the liver, gall bladder and small intestines, according to the Mayo Clinic.It’s most commonly diagnosed in people older than 50. When it is diagnosed, it is usually in later stages, which means it is more difficult to treat.Symptoms include:Yellowing of skin and eyesItchy skinLight colored stoolsFatigueAbdominal painUnexplained weight lossFeverSweating at nightDark colored urineExisting bile duct conditions, chronic liver disease, smoking, diabetes and certain genetic conditions, like Lynch syndrome, can increase risk of cholangiocarcinoma.According to Mayo Clinic, treatment typically includes surgery to remove the cancer, chemotherapy, radiation, immunotherapy, liver transplant and more.