(ABC News) -- For 25 years, Rick and Erica Kaitz were volunteers in the world of cancer research and fundraising, living a good life in Boston with their two daughters and spending five months a year in their second home in Hawaii.
That was until last June, when Erica, 52, was diagnosed with a rare form of uterine cancer -- myxoid leiomysarcoma (LMS). Fewer than 150 patients in the United States have the disease, which is poorly understood and for which research is virtually unfunded.
"Our life was totally altered," said Rick Kaitz, 58 and an attorney. The couple, married for 27 years, have two adult daughters. "We were enjoying life, cutting back on work. The kids were out of the house and we were very much in touch."
Now, Kaitz is on family medical leave and is the main caregiver at home, driving back and forth to the Dana Farber Cancer Institute, and on a quest to find a cure to save his wife.
"I think what drives me is trying to figure out this cancer," he told ABCNews.com.
Since the early 1990s, the couple has ridden or volunteered with the Pan-Mass Challenge (PMC), which raises money for cancer research and treatment at Dana-Farber through an annual bike-a-thon that crosses the state. For much of that time, Erica Kaitz has been on the PMC's head staff.
In the last three decades, the organization has raised $375 million, more than any other single athletic fundraising event in the country.
And now Rick Kaitz has organized a PMC team of more than 100 runners and cyclists to raise $1.5 million for the foundation he created -- the Erica Kaitz LMS Research NOW Fund at Dana-Farber so that scientists can study these rare sarcomas.
Erica was diagnosed with what her doctors thought was a benign uterine fibroid. A partial hysterectomy revealed that it was an LMS, a cancer with no standard of care for treatment.
Sarcoma in general occurs in less than 1 percent of the population, said Dr. Suzanne George, medical oncologist at Dana-Farber and Erica Kaitz's doctor.
"LMS is a sub-type of soft-tissue sarcoma," she said. "It can originate in any part of the body, but the uterus is one of the more common locations of this uncommon cancer."
About 85 percent of all women have uterine fibroids, according to George, and the chances of a suspected fibroid being this type of sarcoma are about 1 in 10,000.
"The challenge is that we don't have any way of identifying which ones of those fibroids may later be identified as sarcoma."
Some doctors speculate that new non-invasive techniques for removing fibroids -- more common now than surgery -- can actually unleash these hidden and aggressive sarcomas.
"The challenge is, we need better tools to ID these rare tumors up front to see if we need to change management at the beginning," she said of treatment for common fibroids.
LMS is so rare it is considered an "orphan disease," one that so few patients have, that there is insufficient funding for research and treatment, and pharmaceutical companies have no incentive to create potential drugs because profits will be negligible.
But the Kaitz fundraising will enable the Dana-Farber research team, led by Dr. George Demetri, senior vice president for experimental therapeutics, to learn more in collaboration with other scientists from top universities.
Demetri was instrumental in demonstrating that Gleevec -- one of the first examples of targeted cancer therapies -- was effective in treating gastrointestinal stromal tumor, a form of sarcoma. His work has led to the FDA approval of several other "smart drugs" for cancer.
An estimated 12,000 to 15,000 Americans are diagnosed with sarcomas each year. Of those, only about 3,000 to 4,000 are leiomysarcomas.
"Erica has a particularly unusual subtype -- at most only 5 to 20 a year," said Demetri. "It looks like it acts differently than other sarcomas and we worry that its behavior is more aggressive."
Though there are many clinical trials for sarcomas and LMS, there are few for her subtype myxoid, which means "mucus."
After his wife's diagnosis, Rick Kaitz consulted with three top medical institutions -- Dana-Farber, New York's Memorial Sloane Kettering and Duke University in North Carolina -- and each offered different opinions on how to best treat the disease. None could promise a good outcome.
"One thing we learned, and this is not the case with all rare cancers, it's really kind of trial and error," said Rick Kaitz. "It's like going to Vegas and playing craps. You see if something works and then you try something else. You really don't know what is driving [the cancer] and what works and what doesn't work."
Erica Kaitz underwent a second surgery at Brigham and Women's Hospital in Boston, but a month later, there was explosive tumor growth in her abdominal and pelvis. Doctors at Dana-Farber began chemotherapy with IV treatment, once every three weeks.
"Things slowed down," said her husband, but after seven cycles over 21 weeks, "it stopped working."
For the last 10 months, doctors have tried a variety of drug therapies.
"In the most successful type of targeted therapy [in other sarcomas], we have identified the mutation and the short circuit and the cell that shuts off the short circuit," said lead researcher Demetri. "In Erica's type, nobody knows where the short circuit is or what they are. The challenge to develop an elegant targeted therapy is basically impossible."
He said Kaitz's funding may help scientists understand more about this class of tumors and help a larger group of patients down the road, but may not provide any benefit for Erica.
"What does it take to be game-changing?" asked Demetri, who will also ride in the PMC race. "It's important to manage public and private expectations. We are incredibly grateful for the support of orphan research. It's hard to get research funding even for the common diseases and for the rare ones, almost impossible."
But with such a complex challenge, even "a billion dollars" may not yield immediate answers. "But, as I tell Rick and Erica," he said, "you never know when we are going to trip over the next discovery."
Today, Erica Kaitz is "hanging in there," according to her husband, who does all the cooking, shopping and organizing of her multiple medications.
"It's been a total role reversal," he said.
She suffers side effects from therapy and Kaitz worries about cardiac damage with the latest drug. "For her, it gets a little old and tiring," he said. "She has no hair and fatigue and it's hard making the bowels work."
"She appreciates everything I am doing but I don't think she particularly likes being the patient," he said. "We don't spend a lot of time talking about regression and we try to enjoy the good days, and there are a fair number. But many days are not so good."
Rick Kaitz said he feels as if he has become a "research scientist" as he desperately works against the clock to raise funds to save his wife. He also knows that in the $35 billion war on cancer, his foundation's $1.5 million contribution is "peanuts."
"But it's peanuts that will be driving the largest LMS research initiative ever taken," said Kaitz. "It's exciting, but it's also pretty pathetic. …I am not poo-pooing breast cancer or prostate cancer -- no one wants to get any cancer, but you are better off with one of those rather than one that is not understood."