From patient to advocate

February 29 is Rare Disease Day

cropped IMG_1244His wife Nancy couldn’t take the snoring anymore, so after a couple of months Dan Nagridge went to ask his doctor if he had sleep apnea.

He ended up at the University of Michigan Health System, with a surprise diagnosis: cancer at the base of his skull. It was chordoma, a slow-growing cancer that’s extremely rare, pushing on the back of Dan’s throat that made him start snoring.

“The cancer starts from tissue that was left when he was forming as an embryo in his mother’s womb,” says Erin McKean, M.D., MBA, a U-M otolaryngologist, or ear, nose and throat doctor, and Dan’s surgeon. “We don’t know why people develop this cancer, so we’re very invested in advancing the research.”

Chordoma occurs in about 1 in 1 million people, and at the skull base, it’s even more rare – closer to 1 in 1.5 to 1 in 2 million people have what Dan was diagnosed with last spring. Dr. McKean sees about four chordoma cases per year.

“I had never heard of it before,” Dan says. “It’s kind of a dream, the whole year and everything I’ve been through.”

“Dan’s cancer was extensive, growing behind his throat and airway, the back of his nose, and around his spinal cord and important blood vessels heading up toward the brain,” Dr. McKean says. “We knew we had to have an experienced team on board.”

McKean brought in more physicians, including neurosurgeons Stephen Sullivan and Paul Park, to help remove the chordoma and stabilize Dan’s spine. In addition, McKean found a different cancer in his thyroid, which she also removed surgically the day before his chordoma operation. After the cancer removal and recovery, Dan returned a few months later for radiation with Avraham Eisbruch, M.D., targeting any remaining microscopic tumor around the spine and throat.

The rarity of chordoma and the fact that it often returns years down the road means Dan was uniquely driven to help. He donated the tissue removed in his surgery to the Mark Prince lab at U-M, which has experience in establishing chordoma cell lines. The Prince lab created the first skull-base chordoma cell line in the world and has multiple other cell lines growing.


Chordoma growing in culture in the Mark Prince lab at U-M.

“We’re growing Dan’s chordoma cells in the lab right now, but the cells grow so slowly they won’t be considered a cell line for another year or so,” says U-M researcher John Henry Owen, M.S.

Eventually, Dan’s tumor may establish the first cervical spine chordoma cell line, a big landmark for identifying causes and cures for this rare cancer.

“I thought, if I have an opportunity to help, I should take it,” Dan says. “I could either be upset about what I’ve been through the last year, or turn it into a way to help others.”

Dan has stopped snoring and is back to work now. Given the extent and nature of his tumor, Dr. McKean knows that Dan’s chordoma may recur years down the road. Her hope is that basic science research will be far enough along by then, in part thanks to Dan’s own tumor, that we’ll have improved treatment and prevention the next time around.

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Erin McKean, M.D., MBA, is associate professor of otolaryngology at the University of Michigan. She completed medical school at the U-M Medical School, followed by a residency and then a fellowship at the U-M Health System. Dr. McKean’s clinical interests include minimally invasive skull base surgery, benign and malignant skull base tumors, CSF leaks, sinus cancers and head and neck cancer.