Brokaw's multiple myeloma called incurable but treatable

• New treatments are allowing the cancer to be dealt with like a chronic disease
• Experts say Brokaw%2C 74%2C may still have many years ahead of him
• Two decades ago%2C patients often survived only two to three years.

Veteran journalist Tom Brokaw revealed Tuesday that he has a cancer of the bone marrow called multiple myeloma.

Brokaw, an NBC News special correspondent, said he and his physicians have been encouraged by his response to therapy since his diagnosis in August at the Mayo Clinic.

Myeloma experts say Brokaw, 74, could still have many years ahead of him.

Although doctors consider myeloma to be incurable, it is treatable, using new therapies that have transformed it into a chronic disease, says Gary Schiller, a hematologist at UCLA's Jonsson Comprehensive Cancer Center in Los Angeles. Two decades ago, patients often survived only two to three years.

On average, patients today tend to survive about five to seven years after diagnosis, says Catherine Broome, a hematologist/oncologist at Georgetown's Lombardi Cancer Center in Washington, D.C.

In some cases, patients can survive more than a decade, Schiller says, noting that some "amazing" new therapies "have changed the whole story."

According to the American Cancer Society, there are 22,000 cases of myeloma diagnosed each year, with 10,700 deaths. The disease is more common in men, and typically diagnosed in older Americans.

The disease affects a type of immune system cell called a plasma cell, which makes antibodies, Broome says. Antibodies are crucial for fighting disease. As cancerous cells grow, they take over the bone marrow, secreting substances that cause the bone marrow to dissolve itself, making more room for the cancer. New drugs can help to strengthen and preserve bone in myeloma patients, Schiller says.

Myeloma cells create ineffective antibodies, which cause the kidneys to become filled with a thick, molasses-like substance that impairs their function. Patients may be diagnosed because of bone deterioration, kidney problems or anemia, Schiller says.

Myeloma also can be detected through blood tests that are part of regular care, Broome says.

Patients are typically treated with a cocktail of drugs, including some of the new "targeted" therapies, Broome says. If patients respond well, doctors often recommend a bone-marrow transplant. In these procedures, doctors remove a patient's own bone marrow, treat them with chemotherapy, then transplant the bone marrow back into a patient's body.

Because patients receive their own bone marrow, they don't suffer from the dangerous immune system reactions that occur when people receive donated bone marrow, she says. "Patients tend to tolerate the treatment very well," Broome says.

Thanks to these therapies, "there are plenty of survivors in their 70s and 80s," Schiller says.

In a statement, Brokaw wrote, "with the exceptional support of my family, medical team and friends, I am very optimistic about the future and look forward to continuing my life, my work and adventures still to come. I remain the luckiest guy I know."