Quicker Bone Marrow Collection with ‘MarrowMiner’ Device

Abstract

A plumber's snake isn't the most elegant analogy to describe a new medical device, but that may be the best way to visualize the MarrowMine®, a product developed to extract large quantities of bone marrow with only one or two “sticks” into the donor's iliac crest. The device's inventor says the product can be used in the outpatient setting, is fast, is minimally invasive, and requires only local anesthesia. A catheter is inserted only once or twice to collect the required volume of stem cells for transplant, rather than the hundreds of punctures needed now. A small clinical trial has shown that the marrow collected delivers more than 10 times the stem cell activity compared with the standard method of collection, said the inventor, Daniel Kraft, MD, a pediatric oncologist at Stanford University School of Medicine and instructor in Pathology at the Stanford Institute for Stem Cell Biology and Regenerative Medicine. TED Video A video being worth a thousand pictures, the best way to understand the device is to view Dr. Kraft's speech in February at the TED2009 conference, which features new ideas from the worlds of technology, entertainment, and design, where the product was unveiled: http://blog.ted.com/2009/07/a_better_way_to.php In the video, Dr. Kraft explains that he came up with the idea while performing a collection procedure during a postdoctoral fellowship at Stanford: “I was standing there thinking that there must be a way to do this that doesn't make the operator's wrist sore and/or leave the patient's iliac crest looking like Swiss cheese.”DANIEL KRAFT, MD, the device's inventor, noted that MarrowMiner can be used in the outpatient setting, is fast and minimally invasive, and requires only local anesthesia. The related catheter has to be inserted only once or twice to collect the amount of stem cells needed for transplant, rather than the hundreds of punctures needed now.There is an ongoing debate regarding the use of stem cells derived from peripheral blood and those derived from bone marrow. Dr. Kraft said one practical reason some oncologists prefer stem cell collection from peripheral blood over bone marrow is that it's easier for the physician to sign an apheresis order. But recent studies have shown that the rate of chronic graft-versus-host disease is higher with mobilized peripheral stem cells than with bone marrow. “And even if long-term survival is the same for both stem-cell sources, there is more morbidity with peripheral blood,” he said. The MarrowMiner has a flexible, powered catheter with a wire-loop tip that stays inside the cancellous bone and follows the contours of the hip as it moves around. “We can do multiple passes through that same entry, no robots required,” he said. The flexible 10-gauge “flexshaft” catheter rotates at slow speed and moves through the cancellous bone—“But it doesn't pop out when it hits the cortical bone on the side; it follows the curvature of the bone,” he said. “That allows long passes.” Dr. Kraft received an “Advanced E-Team Grant” in 2002 from Stanford to form an E-Team to develop the device. That team evolved into StemCor Systems, Inc., a company Dr. Kraft founded while still in his fellowship. Vartan Ghazarossian, PhD, is the company's president and Dr. Kraft serves as a consultant. Regenerative Medicine While Dr. Kraft invented the device to harvest bone marrow for stem cell transplantation to treat malignancy, providing stem cells for transplant in hematology patients is a relatively small market, since only about 60,000 transplants are done worldwide yearly, he said. The demand for stem cells used in regenerative procedures, however, will mount to the hundreds of thousands, he predicts. Adult stem cells from bone marrow are being tested as treatment for many conditions such as heart disease, vascular disease, orthopedics, tissue engineering, in neurology to treat Parkinson's disease, and diabetes.WILLIS NAVARRO, MD, of the National Marrow Donor Program said he knew