Liquid biopsy reveals ability to tailor treatment

Cholangiocarcinoma (CCA) is a cancer that arises from bile ducts/channels draining bile in the liver and often includes the gallbladder cancers. CCA is the second most common form of cancerous liver lesions. In 2017, Linda Kilcrease came to Pashtoon Kasi, MD, MS (then at Mayo Clinic), with metastatic cancer, but it was not amenable or safe to do a generous biopsy for genetic testing. Kasi performed a liquid biopsy, and revealed  that her tumor was HER2 amplified (+++ positive). Even though anti-HER2 dugs are not approved for this kind of cancer, increasingly literature is supporting its use. Kilcrease’s care team was able to get trastuzumab and pertuzumab (two anti-HER2 drugs) approved for her as off-label treatment.

Unlike her previous experience with chemotherapy, Kilcrease says her quality of life increased dramatically following the application of the HER2-targeting treatments. While previously unfamiliar with a liquid biopsy, Kilcrease now credits that method with this serendipitous finding of HER2 treatments and with her high quality of life. Kasi detailed her case in an article published in Nature Precision Oncology earlier this year.

Liquid biopsy is a less-intrusive test used to identify types of cancers through blood sampling. The term biopsy is a misnomer since no actual biopsy is being performed and it is essentially looking at circulating tumor DNA (ctDNA) in the blood of the patient.

Before a conference, Pashtoon Kasi, MD, MS, Clinical Assistant Professor in Hematology, Oncology and Blood & Marrow Transplantation, discusses the increased application of liquid biopsies to find alternative treatments for cancers.

“The most recent consensus statement from ASCO [American Society of Clinical Oncology] was that in summary these liquid biopsies were ‘not ready for primetime,’” Kasi said. “However, work at ASCO this year by our group in addition to our collaborations, we highlight some of the scenarios where this is probably ready for use in actual clinical practice.”

Kilcrease said she much preferred the liquid biopsy to the liver biopsy she had performed previously. Kasi says the liquid biopsy provided all the relevant information that could have been acquired on an actual tissue sample, which is often a challenge in patients with CCA or other situations where it is not safe to get a generous biopsy specimen.

“I think it was because of liquid biopsy that everything came into place,” Kilcrease said. “I have not had any nausea. I’ve lived a perfectly normal life. I’m still able to work and everything. I go to church every Sunday and Wednesday night and I have grandchildren. All that keeps me busy.”

Because of her proximity to Mayo, Kilcrease still receives treatments there, but travels regularly to Iowa to see Kasi for evaluation. On a recent visit to Iowa’s Holden Comprehensive Cancer Center for a checkup, Kilcrease and her husband, Ronnie Kilcrease, sat down for a brief conversation with Kasi about their experience.

In 2017 Linda Kilcrease was experiencing severe nausea. Her doctor told her she had innumerable inoperable lesions on both sides of her liver. Kilcrease was referred to Pashtoon Kasi, MD, MS, Clinical Assistant Professor in Hematology, Oncology and Blood & Marrow Transplantation.

While on chemotherapy initially, Kilcrease experienced a drastic drop in her quality of life. After performing a liquid biopsy, Kasi found Kilcrease had the HER2 amplification (+++ positive), which changed her treatment options.

Kilcrease describes her life after liquid biopsy as “perfectly normal” and “nausea-free.”

Kilcrease’s husband, Ronnie Kilcrease, speaks about the lack of energy and nausea his wife experienced during her first few months of cancer. Treatment options, discovered through liquid biopsy, improved Linda’s quality of life.

Ronnie Kilcrease describes the pain of a liver biopsy. For Linda Kilcrease, liquid biopsy was a less intrusive and less painful method that allowed Kasi to identify a better treatment. (As previously noted, liquid biopsy is a blood draw looking for circulating tumor DNA – ctDNA from the cancer. The term “biopsy” is a misnomer.)