Dr Jagannath on the Potential Role of MRD Testing for Defining "Cure" in Myeloma

"We want to use the most sophisticated test to make sure the patient is actually cancer free. MRD is one component, [but it does not give us] the complete [picture]. Right now, bone marrow [biopsies] are still the gold standard, but technologies are being developed that [may allow us to perform blood tests] instead."

Sundar Jagannath, MBBS, a professor of medicine (hematology and medical oncology) at the Icahn School of Medicine at Mount Sinai and The Tisch Cancer Institute in New York, New York, highlighted the technological and molecular advancements have enabled better minimal residual disease (MRD) detection and allowed for the utilization of MRD as a crucial marker in multiple myeloma. 

One key technological advancement in this context is the next-generation sequencing (NGS)–based assay clonoSEQ, Jagannath began. This sophisticated assay is capable of detecting as few as 1 in 1 million cancer cells, making it an incredibly sensitive tool. Although it has already applied in other hematologic malignancies such as leukemia, B-cell lymphomas, and acute lymphoblastic leukemia (ALL), this same technology is now also applicable in multiple myeloma, Jagannath stated.

However, in myeloma, the definition of cancer-free extends beyond just bone marrow testing, he continued. Although bone marrow is where myeloma primarily resides and remains the gold standard for testing, a patient could still have an MRD-negative bone marrow, yet harbor a small plasmacytoma in other areas, such as a rib or skull. To address this, Jagannath stressed the importance of incorporating whole body imaging alongside bone marrow tests to ensure comprehensive assessment.

He also pointed to advancements in serological testing, where mass spectrometry can detect even trace amounts of cancer protein in the blood or urine. The overarching goal, according to Jagannath, is to employ the most sophisticated tests available to ensure that a patient is truly cancer-free. Although MRD is a vital component in this definition, it is not the sole factor, he clarified. New technologies are being developed that might eventually allow for blood tests to replace bone marrow biopsies, although currently, the bone marrow remains paramount, he concluded.