Tenor-sax virtuoso Michael Brecker [ tickets ] is gravely ill with myelodysplastic syndrome (MDS), a rare and bone marrow disease, and is in need of a stem-cell transplant.

The 56-year-old, 11-time Grammy winner is undergoing treatment at New York's Memorial Sloan-Kettering Cancer Center, the Philadelphia Inquirer reports. All of Brecker's planned concerts have been either postponed or canceled, according to his official website.

"The initial search for a donor (including Michael's siblings and children) has not yet resulted in a suitable match," Brecker's wife, Susan, said in a statement. "Michael's doctors have told us that we need to immediately explore all possible options. This involves getting as many people of a similar genetic background to be tested."

The screening includes a blood test, and a match for Brecker would most likely come "from those of Eastern European Jewish descent," Susan Brecker's message said.

More information about the screening process and stem-cell donation process--which Susan Brecker writes is "no more invasive than giving blood"--is available at the National Marrow Donor Program's website, or by emailing Brecker's management at info@michaelbrecker.com.