Makaila Chenier, 17, found a lump in her neck. As it grew it became more difficult for her to breathe when she'd lie down. Doctors discovered it was lymphoma.

Woman, 28, noticed a neck lump and thought it was from a long cold. It was thyroid cancer While she noticed the bump a few months earlier, she thought it was swollen lymph nodes from a cold.

(Presley Ann/Getty Images for MTV) Tarek El Moussa's thyroid cancer was first detected by a fan who noticed a lump on his neck while watching a marathon of his HGTV show "Flip or Flop" in 2013.

Makaila Chenier, 17, found a lump in her neck. As it grew it became more difficult for her to breathe when she'd lie down. Doctors discovered it was lymphoma.

The cancer had wrapped around my left carotid artery, one of the major blood vessels going to my head and neck—had she injured it during surgery, that could have led to paralysis or even death.