Читать книгу Anti-Aging Therapeutics Volume XIII - A4M American Academy - Страница 24

Advanced MRI scans performed in Europe are not available in the US, nor are certain sophisticated radioactive bone scans, or techniques for evaluating lymph node involvement, allowed in the States at this writing. For example, in 2004, Dr. Jelle Barentsz described a new technique to evaluate cancer spreading to the lymph nodes at the International Congress of Radiology. This uses MRI with ferumoxtran-10, a novel contrast agent called Combidex in the United States. The lymph node technique is termed MRL (magnetic resonance lymphangiography) and ferumaxtran-10 is being used in a wide range of MRI procedures throughout Europe, as it has shown a very good safety record, especially as it does not induce nephrogenic systemic fibrosis (NSF), a recently recognized severe complication associated with gadolinium (Gd)-based contrast agents (GBCAs) when used with patients who have compromised kidney function. GBCAs are used as standard in the United States.

This technology is extremely important since MRI is the best way to image abnormal glands that are hidden or inaccessible at surgery. The imaging shows the size and location of the lymph nodes as well as the presence of cancerous tissue as small as 1/5 inch. This critical piece of information that pinpoints cancer infiltration tells where the spread occurs and allows for accurate treatment planning. The current “gold standard” for lymph node evaluation is surgery called pelvic lymph node dissection. Clearly, this invasive exploratory operation, where the surgeon searches with his hand for hard lumps in the abdomen, cannot find all the tiny sites to which cancer spreads. Moreover, the metastases to nodes are generally subcentimeter and so are likely to be missed clinically and radiographically. In addition, the most reliable sign of metastatic adenopathy is in the perirectal space, which is not routinely examined at surgical dissection. The MRL exam is so accurate that a negative exam translates into a 96% chance that there is no metastatic disease to the lymph nodes. In addition to sparing patients from the risk and pain of surgery, this methodology reduces health care costs.