David Dahl is suffering from a tumor so rare that only 18 other people in the world have it the Ravalli Republic reported.

Dahl has cavernous hemangioma, a tumor that is 35 millimeters in length in his chest cavity. The tumor has wrapped itself around his esophagus, putting pressure on his lungs, heart and blood vessels.

"He has problems breathing," said Dahl’s wife, KC, who is pregnant with the couple’s second child. "It is life-threatening because if it gets any bigger, he could have reduced blood flow to his brain or his heart and it could cause a heart attack or a stroke. He could be paralyzed if it moved to his spinal cord; it could cut off his esophagus entirely."

Dahl is hospitalized once a week. His symptoms include trouble eating and breathing and sometimes his arms and legs become numb.

Doctors told Dahl the tumor most likely is from a birth defect. He had a smaller tumor removed in 1983, which was 11 centimeters in length.

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