Battling stage 4 breast cancer isn’t enough for Michelle Smith. The Cottage Grove woman also is helping other women with the disease — by knitting.

Smith and the volunteers she’s recruited are knitting prosthetic breasts for cancer patients who have had mastectomies. Her group is working with Knitted Knockers (knittedknockers.org), a nonprofit organization based in Washington state that provides lightweight, breathable prostheses out of soft yarn for women who don’t like or can’t use traditional commercial silicone prostheses.

According to Knitted Knockers’ founder, Barbara Demorest, many breast cancer survivors don’t like using silicone prostheses because they find them hot, heavy, expensive and uncomfortable when touching sensitive scar tissue.

Demorest, of Bellingham, Wash., learned that firsthand when her breast cancer was diagnosed and she had a mastectomy in 2011. She wasn’t able to have reconstructive surgery immediately after her operation, and she was told she couldn’t have a typical prosthesis touching her scar for at least six weeks.

“I was really depressed,” she said, because she was self-conscious about going out in public.

Then her doctor told her about the knitting patterns online, and how people were using them to create breast prostheses out of yarns. They could be worn in an ordinary bra, her doctor said, and wouldn’t hurt her scar.

“It was literally life changing for me,” Demorest said.

In 2014, she started a nonprofit to provide the prostheses free to other women, recruiting volunteer knitters worldwide and partnering with medical clinics and doctor’s offices to distribute them.

Demorest said a video tutorial created by her group showing how to make the fabric prostheses has been viewed half a million times. The knitting pattern has been downloaded a million times. She estimates at least 1,000 knitted prostheses are being created every month by more than 450 volunteer groups.

In the Twin Cities, Smith, 46, said her group of about seven volunteers started knitting three months ago. Already, they’ve made about 25 pair of breast prostheses and they’re working with the Breast Center at University of Minnesota Health to distribute the prostheses.

Knitted Knockers asks volunteers to use particular cotton or cotton-blend yarns that have been tested to be washable, soft and breathable. They’re then filled with a poly fiber filling. (Acrylic yarns can be used to make prostheses used for swimming.)

Smith said she’s been surprised how many women are receptive to the hand-knit prostheses. Recently, she was telling a clerk in a yarn store that she was making knitted breast prostheses and the clerk asked for one.

“It’s way more common than anyone knows,” Smith said.

Another local woman, who contacted Smith on the Knitted Knockers website, asked for prostheses for her grandmother in Shakopee who was undergoing a double mastectomy.

“Grandma’s face lit up when she saw them,” Smith said. “This makes her feel a little less scared of the whole thing she’s going through.”

Smith said the prostheses aren’t costly or particularly hard to make. Demorest estimated that a knitter could probably make one in two to four hours, using about $1 to $2 worth of yarn. In comparison, a conventional commercial breast prosthesis can cost $300 to $900.

Smith is working on creating a $15 kit for volunteers, which will include yarn, needles and patterns.

“We’re trying to make it grow,” Smith said of the nonprofit. Knitters who are interested in joining a group or in making a donation can go to knittedknockers.org.

Smith doesn’t need a prosthesis. She didn’t have a mastectomy. Instead, her metastatic breast cancer is being treated with drugs.

“So long as my drugs keep working, I will have a number of years ahead of me,” she said.

Still, she feels a strong connection with the women who receive the Knitted Knockers.

“It’s very personal,” she said of dealing with breast cancer. “It’s such a scary road.”

That’s why she, Demorest and the rest of the knitting volunteers are so happy they can use their needles and their skills to help other women.

“This brings purpose to our knitting,” said Demorest, who added, “ You can only make so many baby booties.”