If you know someone who's benefited from organ donation, you know it's a priceless gift of life.
But you may not know as much about tissue donation, that it has helped fuel a billion-dollar-plus industry.
While there's a lot of good that can come tissue donation, we discovered that there are ways for you to set limits on what happens to your tissues.
To understand the potential for tissue donation, you need to walk in Kim Engelhardt's shoes -- or, more specifically, run in them.
"In December 2000, I was diagnosed with periosteal osteosarcoma, which is a type of bone cancer," she recalled.
It was a tumor in her left thigh bone.
"Being a nurse I had seen so many situations where people did have to have amputations, so that's just what I thought was going to happen to me as well."
But instead, doctors were able to take a bone from a tissue donor and splice it into the areas where they cut out her tumor, saving her leg.
"Since then," Engelhardt said, "I have done a total of seven half marathons and I have completed three full marathons."
And she's now a mother of three.
"Without the donation, without the cadaver bone, my life would have been totally different."
Jill Grandas called tissue donation "life-changing, it's lifesaving, as well." Grandas heads DCI Donor Services, a non-profit that serves Tennessee and three other states.
She said the list of possible benefits from tissue donation is long.
"Women who have to have a mastectomy because of breast cancer can have reconstructive surgery because of tissue donation. Children who have heart problems could have a valve transplant."
Donor organizations are allowed to charge "reasonable fees" for harvesting organs and tissues.
DCI markets tissue from its donors to healthcare providers through full-color catalogues.
We also spotted ads that show for-profit companies selling tissue products, courtesy "DCI Donor Services."
We even found jars of bone tissue "on sale" on one website that even accepts credit cards.
And, in some cases, tissue that DCI gets from donors here in the U.S. can end up being sold in Central America, as well as East Asia and the Pacific.
"Certainly if someone has decided they want to become an organ and tissue donor and they're giving of themselves and they want their give to be used, we will find a place for that gift to be used," Grandas said.
NewsChannel 5 Investigates asked, "And if it cannot be used here in the U.S., that's when it could go overseas?"
"Correct," she answered.
DCI's tax returns show the fees it collects for its services, including both organs and tissues, has increased from $50 million in 2009 to $77 million in 2013.
That's due in large part to deals with companies like LifeCell Corporation, which produces a skin product call Alloderm.
Originally developed as a graft for burn patients, Alloderm is primarily used for mastectomy surgery for breast cancer survivors and reconstruction of abdominal walls.
"When our board looks at companies like that, we have to make sure that they are very much aligned with what our mission is, which is to save and improve lives," Grandas said.
But we discovered some clinics advertising the use of Alloderm for lip augmentation, even for male enhancement.
"I'm not familiar with any company that we work with that does that," Grandas insisted.
Through a letter provided to DCI, LifeCell said that those are off-label uses that have not been approved. They also said they have tracking mechanisms in place to try to prevent it from happening with donated tissue that's been labeled for "non-cosmetic uses only."
"It's not a problem as long as people have been told this is what is going to happen," said Boston University bioethicist George Annas.
Annas said the critical question is: what is DCI telling prospective donors?
"To the extent that families don't know know what's happening, that's the problem, that's the problem," he explained. "And I think that some of these companies must think if families knew they wouldn't consent, and that's a big problem."
We checked the website for the Tennessee Donor Registry and eventually found where donors could designate that their tissue could be used for "life-saving and reconstructive purposes only," be "donated only to non-profit organizations," and "be used in the United States only."
But we discovered that, if you fill out a generic form to become an organ and tissue donor, you won't find any of that.
"Our website and our information was consistent with how other programs work that are like ours," Grandas said.
While the DCI official said what they were doing was legal, she also admitted there was room for improvements, making those kinds of disclosures easier to find.
"People are dying without the work that we do and we don't want anything to hinder it, we want to do everything to help it."
As a result of questions raised by NewsChannel 5 Investigates, DCI has beefed up the disclosures it provides online on the Tennessee Donor Registry.
If you've already signed up as a donor, you can go there to set your preferences. And if you're not already an organ or tissue donor, you can actually go there to sign up.
To go to the Donor Registry, click here.