Debbie Sardone started Cleaning for a Reason to provide free housecleaning services to women undergoing cancer treatment. The nonprofit organization has donated more than $5.5 million worth of housekeeping services to cancer patients over the last decade.

But it’s the woman Sardone never got to help, the one who inspired her to start the foundation, that she thinks about every day.

Cleaning for a Reason staff, and some of the patients they have helped. Courtesy of Cleaning for a Reason

The potential client had called Sardone’s cleaning company seeking an estimate, which she couldn't afford because chemotherapy and radiation sessions left her unable to work.

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“She said, ‘Maybe I’ll call you when I can afford it,’ and hung up. And that was before Caller ID. I had no way to call her back,” Sardone told TODAY.com. “I made a decision and shared with my staff that day that the next time a woman battling cancer called our office needing help with her home, if she couldn’t afford it, we would just give it to her completely for free.”

Years later, Sardone shared the story while speaking at a national convention of cleaning professionals, many of whom expressed interest in adopting a similar policy.

“They were big companies, little companies, mom and pops who do the work themselves, and even big franchises,” said Sardone, 56. “Many of them came up to me after my workshop and said, 'I want to do that in my town.'”

Debbie Sardone, Cleaning for a Reason founder Courtesy of Cleaning for a Reason

That prompted Sardone to create Cleaning for A Reason, a nonprofit organization celebrating its 10th anniversary this year. The group has helped more than 19,000 cancer patients so far.

Cleaning for a Reason gets about 1,400 requests for service each month. It works with companies throughout the nation and Canada willing to provide cancer patients with one free cleaning a month for four months. While the businesses — which must be insured and conduct background checks on its workers — do not charge the women for their services, their employees are paid for their work.

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Stacey Steele said Cleaning for a Reason “truly changed my life” nearly two years ago right after undergoing surgery for ovarian cancer. At the time, her health and the welfare of her children were her top priorities — not vacuuming rugs and dusting furniture.

“My focus was on trying to keep things routine and normal for the kids and getting my health back. I wasn’t thinking about cleaning the bathroom,” she said.

“Knowing your house is being taken care of when you don’t have the energy to get out of bed helps lift a huge stress from you," she said. “At the time, I was so weak that showering would literally be my main activity for the day. And when you’re not feeling good, the last thing you want to do is go into a dirty bathroom.”

Staff of Debbie Sardone's private cleaning company, a Cleaning for a Reason partner that helps women with cancer. Courtesy of Cleaning for a Reason

R.J. Patel has helped more than 240 cancer patients since his company, PCT Clean, partnered with Cleaning for a Reason in 2006. He said he jumped at the chance to help women during this "extremely vulnerable time."

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“Women take a lot of pride in their home, and when the home is not where they want it to be, their psychology is hurt, and when they’re hurt mentally, their healing takes longer,” he said.

“It’s just a pleasure to serve these people. When we get the call to go out and literally take care of them, I know that we’re doing God’s work in their homes.”

PCT Clean owner R.J. Patel said his company has provided free housecleaning services to 243 cancer patients through its Cleaning for a Reason partnership. PCT Clean

Cleaning for a Reason is limited by the number and location of the cleaning businesses on its roster, and Sardone said she is desperate to find more partners.

“There are probably 25,000 cleaning services in the United States. We have only 1,150 of them. We want every maid service in the country to join, but most have probably never heard of us,” she said. Because of her certainty in the “power of benevolence,” she said she knows "others would join and donate if they just knew we were around.”

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Sardone has owned a private cleaning business for more than 30 years. She also owns a business that manufactures natural cleaning products and a consulting service for cleaning companies.

“My whole world is about cleaning. If there’s dust or a toilet, my name might be on it,” she said with a laugh. “I understand the needs of cleaning and how difficult it is. And I understand how good it makes you feel when you have a clean house.”

But when the service can easily average more than $120 for a single-family home, she also understands not everyone can afford the service, especially when going through a health crisis — like the woman who called her nearly 20 years ago.

“I think of her nearly every day,” Sardone said. "I am continually reminded of how many women could use our help."

Follow TODAY.com writer Eun Kyung Kim on Twitter.