Biomarker Testing Increasingly Important, But Still Challenging, in iCCA

Biomarker testing is becoming a prevalent component of treatment for patients with intrahepatic cholangiocarcinoma (iCCA), but a new report by interdisciplinary experts shows several hurdles to be cleared before its use can be fully optimized.

The paper, published in The Oncologist, says successful biomarker testing requires careful planning and coordination from team members across disciplines.

The authors noted that patients who receive a diagnosis of advanced or metastatic iCCA typically receive chemotherapy in a palliative care setting. “However, the past decade has witnessed the advent of biomarker testing and precision medicine that enables tailoring of targeted therapies to improve patient outcomes,” they said.

Targeted therapies rely on biomarker testing, but the investigators said such testing comes with a set of challenges in iCCA. Many oncologists run into problems accessing the tissues necessary for next-generation sequencing, and there are no standard image-guided liver biopsy and processing guidelines for biomarker testing.

The authors of the new report include a gastroenterologist, interventional oncologists, medical oncologists, and pathologists. After discussing various challenges and considerations, the experts offered a list of “guiding principles” to optimize tissue collection and processing.

Among them, the authors said the current evidence supports the combined use of core needle biopsy and fine needle aspiration (FNA) to acquire tissue samples, but they said the process has not yet been fully standardized and more research is needed to do so.

Once samples are obtained, rapid on-site evaluation (ROSE) by cytologic evaluation of FNA biopsy smears or touch preparations from core samples can help improve tissue yield and specimen adequacy, the investigators wrote. Still, due to cost and personnel burdens, ROSE is not widely available they said.

The experts said splitting core specimens into 2 specimens, one for diagnosis and one for biomarkers, is “essential” and will help ensure there is sufficient tissue for biomarker testing. They added that microdissection can also be used to perform biomarker testing on specimens that might otherwise be unevaluable.

Ensuring adequate samples is also about communication, the authors said. “Adoption of strategies such as inclusion of interventional oncology in the multidisciplinary team and utilization of a biopsy scoring system and standardized biopsy requisition form can improve sample quality and biomarker testing success rates, as well as help identify high-risk patients to minimize complication rates,” they wrote.

The investigators added that several other questions remain open: There is not yet consensus on when to perform biomarker testing in patients with resectable disease, it is unclear whether treatments such as chemotherapy might alter the biomarker profile of CCA, and it remains unknown whether there are differences between the biomarker profiles of primary and metastatic lesions, they said.

In their conclusion, they said regular communication and the integration of biomarker testing into workflows are key. They also reiterated that it is important to include interventional oncologists into multidisciplinary health care teams, in part so they can help educate other team members on the importance of biomarker testing. Telemedicine can be a meaningful way to bring insights from academic oncologists into the community-care setting, they said.

Madoff and colleagues said communication and coordination can help overcome the challenges associated with image-guided biopsies for biomarker testing.

Reference

Madoff DC, Abi-Jaoudeh N, Braxton D, et al. An expert, multidisciplinary perspective on best practices in biomarker testing in intrahepatic cholangiocarcinoma. Oncologist. Published online August 4, 2022. doi:10.1093/oncolo/oyac139