Martina’s article highlights the progress of developing (cfDNA) Blood Biopsies – a Cell free NON Tissue method.

The key point is that Blood Biopsies accuracy is fast improving. For CCA patients many if not most are diagnosed at a stage where surgery and therefore a (solid) biopsy is not an option.

An IHC test for MSi – high (and PD-L1 Expression) is a critical immediately upon being Newly Diagnosed. MSi-high is known to be a strong predictor that a patient will be a match for a “Check Point Inhibitor” immunotherapy such as Keytruda or Nivolumnab. IHC = Immunohistochemical  

Article Source – ONClive Read the full Article – Well worth the effort

Cell-free DNA (cfDNA)-based detection of microsatellite instability (MSI) status was found to be highly concordant with tissue-based MSI testing, according to results of an analysis recently published in Clinical Cancer Research

Findings showed that incorporating MSI detection into the 74-gene panel liquid biopsy assay Guardant360 demonstrated high concordance in approximately 1145 cfDNA samples for which MSI status based on standard tissue testing was.

The National Comprehensive Cancer Network’s clinical practice guidelines recommend MSI as a biomarker in at least 9 malignancies: esophageal/esophagogastric cancer, cervical cancer, pancreatic cancer, ovarian cancer, colorectal cancer (CRC), prostate cancer, gastric cancer, cervical cancer, and cholangiocarcinoma.

MSI status is generally tested via standard tissue biopsy; yet, MSI testing is underutilized in clinical practice due to lack of viable tissue, the inherent invasive nature of tissue-based biopsies, and a lack of routine testing. If detected, MSI-high (MSI-H) status is a predictive marker to receive treatment with immunotherapy.

Currently, pembrolizumab (Keytruda) is approved for the treatment of adult and pediatric patients with unresectable or metastatic, MSI-H or mismatch repair deficient (dMMR) solid tumors that have progressed after prior treatment and who have no satisfactory alternative treatment options, as well as for patients with MSI-H or dMMR CRC following progression on a fluoropyrimidine, oxaliplatin, and irinotecan.

The combination of nivolumab (Opdivo) and ipilimumab (Yervoy) is also indicated for the treatment of adult and pediatric patients ≥12 years with MSI-H or dMMR metastatic…

patients reported as having MSI-H tumors, and 99.5% of those having microsatellite stable disease, leading to an overall accuracy rate of 98.4%; the positive predictive value was 95%.

Moreover, compared with IHC, concordance of cfDNA MSI with PCR and NGS was significantly higher….

“Following the tissue-agnostic approval of pembrolizumab for patients with MSI-high tumors, a barrier to improved outcomes for many patients is the awareness and testing of MSI status,” study co-author Scott Kopetz, MD, PhD, associate professor of Gastrointestinal Medical Oncology at The University of Texas MD Anderson Cancer Center and co-author of the study, stated in the press release. “By adding MSI testing into a noninvasive screening panel, clinicians can routinely scan for this prognostic factor without ordering a separate test.”

The study authors concluded that this assay enables highly accurate detection of MSI status that is concurrent with comprehensive genomic profiling, and expands immunotherapy access for those with advanced disease.

ACCURATE BLOOD BIOPSIES

A significant barrier to obtaining the critical MSI-high and PD-L1 information has been removed.

MSI-High

There are many Patients who are unable to discover if they are MSI-high due to not being able to extract tissue – Blood biopsies are over coming this obstacle and more patients will discover their status and immunotherapy options.  – Immunotherapy is the only potential cure outside surgery options.

SURVIVAL

Many more patients will be exposed to more options to improve outcomes and potentially be cured. Currently very few patients are tested for MSI- high – PD-L1 . Always INSIST that your Oncology team discover your MSI Status immediately upon diagnosis, this is potentially lifesaving knowledge.

Steve